Space Warfare XIII: The Human Factor
Discussion of the recent post on Interstellar Empire led to a question that until now failed to get a post of its own: the role, in space warfare, of drones versus ships carrying human crews. Consider this deficiency now corrected.
A few provisos apply. Set aside for now the question of whether warfare, as we have known it and too much loved it since the Iliad, may be obsolescent as a viable mode of conflict among post-industrial communities.
Also set aside the Plausible Midfuture, a place where warfare in deep space is doubtful even if Earth orbital space is armed to the teeth. Set aside as well the general messiness of warfare on planets; my concern here is with space combat. We are dealing here with space armadas, a concept that is demi-operatic at least.
Will these armadas be made up primarily of warships with human crews - the familiar classical vision - or largely of robotic craft?
A lot of this comes down, I would argue, to good old money. The first 50 years of deep space exploration have been exclusively robotic because robotic spacecraft are cheaper. They are cheaper for several reasons: They can be much smaller; except for sample returns they don't need to come back; and in fact they don't even need to always get there.
So far as I can recall, every mission to the outer planets has (so far) been a success, but we only reached the point of batting .500 against Mars since I launched this blog. Such a loss rate was regarded as acceptable for human missions in the 16th century, but not in the 21st. (The more so because the enormous cost of human spaceflight, and resulting high profile, makes human spaceflight losses more controversial than, say, helicopter crashes.)
The situation in warfare is somewhat different, because soldiers are in some fundamental sense expendable - many of our military traditions are, in one way or another, built around that fact. But they are not lightly expended, if only because high quality crews are costly to train and difficult to replace. For post-industrial societies, where untimely death is no longer a sad commonplace, public resistance to casualties may be problematic even for authoritarian regimes.
Cost and risk of losses, taken together, are ample reason for the designers of combatant spacecraft to automate them so far as is practical. But how far is practical?
Kinetic weapons will have no human crews, for obvious reasons. There are almost equally strong reasons not to put crews aboard the buses that deliver them. Kinetics are most effective in a single wave that saturates defenses - the faster they are thrown the harder they will hit, and the less time the defense will have to stop them. This argues for a bus that uses its full delta v for maximum closing rate, rather than holding back propellant in order to recover the bus. For its basic mission it need not be very sophisticated, and you will not be re-using it anyway, at least not anytime soon.
So it is probably cheaper to make the bus expendable.
Lasers are a different matter, as are alternatives such as particle beams. (And for that matter kinetics, if these are slung on their way by coilguns. Flip side, bomb-pumped lasers are expendables, with military properties similar to kinetics.) A laser star is inherently reusable, and suited to missions, such as blockade or maintaining a 'presence,' in which repeated engagements may be required. A laser and its associated optics are also presumably sophisticated equipment. On all of these grounds putting a crew aboard a laser star seems much more plausible than putting one aboard a kinetic bus.
But what exactly would the crew be called upon to do? No gunners' mates are needed to shove photons into the breech, or even aim the laser. Actual precision aiming of the beam will be automated in any case, and assigning targets can be done from a few light seconds away.
The other traditional role of ships' crews is maintenance and repair. But drive engines and megawatt lasers do not, so far as I can see, provide much scope for onboard servicing, let alone damage control during battle. Repairs of either one pretty much need the services of a cageworks. Occasional replacement of smaller failed systems, or whacking balky parts with a wrench, can be done by service teams based elsewhere - at a space station, for defensive orbital forces, or aboard a tender for deep space constellations.
It is a peculiar fact that both many space emergencies - such as onboard fires or air leaks - and much of the corresponding scope for human emergency repair, relate specifically to life support habs. (Propellant tanks can also leak, but offer precious little chance of onboard repair.) I suspect, indeed, that life support maintenance will be a major role of space crews. But this sets up an odd circularity. Take away the hab and you eliminate many of the emergencies that a crew could respond to.
The final role for humans in space combat is command and control, especially rules of engagement decisions. We might not want to trust even high level AIs with these decisions - either because we are not quite sure of their motives, or because they have no motives at all, and so can free us of everything but the need to decide. But the scale and probable tempo of space combat are such that - as mentioned above concerning target designation - these functions generally don't need to be aboard the weapon platforms. Why not offload them to the 'tender' that provides teams for the occasional maintenance call?
Back in Part III of this series I gave the following description of a space combat constellation:
Taken as a whole you might call it a fleet. But it more nearly resembles a mobile, distributed, and networked fortification, deploying in action into a three-dimensional array of weapon emplacements, observation posts, and patrol details, all backed up by a command and logistics center.But even supposing that a main battle force is built along these lines, what about smaller independent mission packages - the equivalent of a cruiser, for example, for patrol missions?
Contrary to the (understandable!) assertion of a well known Evil Website, space is not an ocean. At sea, a single 10,000 ton ship has major advantages over four 2500 ton ships. It is more seaworthy, far more comfortable for its crew, harder to sink, provides a higher and dryer command for guns and sensors, and can maintain higher speed with less power and fuel consumption.
In space these considerations apply with far less force, if they apply at all. A single large hab pod is likely preferable to several smaller ones - but only the command ship / tender needs a hab pod at all. And the other force elements can be carried as riders, if desired, separating only to deploy for combat.
If your propulsion tech involves an electric drive powered by an external reactor, which also supplies the primary laser, you want to match the drive, reactor, and laser, which does argue for putting them together aboard the same spacecraft. And you might reasonably be less than comfortable about separating the crew hab from the main drive. But if your setting has fusion drive, or any self-contained drive, this is much less a consideration.
One other human-factor consideration to keep in mind was brought up in the linked discussion by commenter Tony: What happens to the morality of warfare - such as it is - when no soldiers put themselves at risk to fight it, because the fighting is all done by robots?
In the scenario I have outlined above this is not really the case. The constellation has a human crew, aboard the command ship / tender, even if it is 'behind the lines' relative to the weapon platforms. If the combat units of its constellation are defeated the crew must retreat, surrender, or face destruction - the choices that have always faced combatants who were disarmed in battle rather than killed outright.
Discuss.
Related Links:
Atomic Rockets, of course - especially, but not exclusively, the pages on space warfare.
And previously in the Space Warfare series on this blog:
I: The Gravity Well
II: Stealth Reconsidered
III: 'Warships' in Space
IV: Mobility
V: Laser Weapons
VI: Kinetics, Part 1
VII: Kinetics, Part 2 - The Killer Bus
VIII: Orbital Combat
IX: Could Everything We Know Be Wrong?
X: Moving Targets
XI: La Zona Fronteriza
XII: Surface Warfare
Also ...
Battle of the Spherical War Cows: Purple v Green
Further Battles of the Spherical War Cows
Plus
Space Fighters, Not
Space Fighters, Reconsidered?
And, indulging in heresy -
Give Peace a Chance
The image shows Achilles fighting Hector.
883 comments:
«Oldest ‹Older 601 – 800 of 883 Newer› Newest»Milo:
"Nearly any rocket can be rigged as a crude missile. Therefore, the absolute minimum capability a warship needs in order to be effective is the ability to disable and dodge a civilian ship that's on a collision course with it."
First of all, that's not hard -- rendezvous is in the class of hard to achieve maneuvers when it's an actual mission objective and both spacecraft cooperate. Second, people aren't going to be using their hard to come by spacecraft as kinetic kill vehicles unless in extremis similar to that motivating kamikazes in WWII.
It depends somewhat on the class of spacecraft - a spacesuit backpack can likely be jury rigged to be an 'acceptably crude' KKV. (A ship puts it onto intercept course, then you chuck it out the airlock.)
Even spacesuit backpacks aren't a dime a dozen, but if you can't spare a few of them, you should probably seek mutual understanding through dialogue.
On Ferrell's point, I would add that there is a huge contextual difference between warfare in Earth orbital space and space warfare anywhere else.
The former can happen, in some form, between Earth powers at any time from the present day on. (Or, in a way, from the 1960s on!) There are near-space assets, such as spysats, that highly relevant to conflicts between terrestrial great powers.
Warfare in deep space (in the inclusive sense, not just 'the middle of nowhere') is only plausible once there are deep space assets of strategic consequence.
In a perverse way, the more peaceful relations are on Earth in the next couple of hundred years, the more credible subsequent space-centric conflicts become. If, for example, space is demilitarized WRT the great powers on Earth, no one will have massive orbital forces that can potentially be adapted to deep space operations.
The problem with using auxiliary spacecraft as guided missiles is that they're not euqipped with guidance sensors and navigation computers. One would have to sacrifice existing sensors and computer hardware built for these purposes, but you get no more than those already existing on the spacecraft you need for launch, and that you don't want to disable anyway. Or you would have to cobble together guidance hardware and software out of other assests. What are those assets, and what do you sacrifice to free them up for use on weapons?
WRT PMF warfare, I think the most likely places for it to first occur will be in the orbitals wherever more than one power has an interest. But for a long time the power that wins in the Earth orbitals is the one to eventually win everywhere, because it will be free to send replacements/reinforcements to its forces at Mars or wherever, and expeditions to other places to not under its control to effect compliance. So powers may have small squadrons at key points, but their focus still has to be on the Earth orbitals, because they control access to space. Period.
While I am an enthusiastic proponent of Laserstars and other exciting high tech items, I am noting more and more that we have ignored the most important human factor of all:
Why are we fighting in the first place?
What sort of McGuffinite justifies building space warships the size and cost of modern day aircraft carriers (and sending them off in task force sized constellations)?
The only real issue I can see that would draw people in this direction (or different approaches to the same solution) is the defense of Earth against space impacts. Most other scenarios like orbital control or occupying colonies to prevent them from diverting a space rock in our direction or force them to comply with the latest bureaucratic initiatives from Earth only require modest spacecraft and capabilities (even a putative orbital laserstar can be derived from 1980 era SDI speculation; a Hubble sized spacecraft in high orbit to escape LEO clutter and have a wide horizon).
This is also a rather one sided affair; EarthForce has giant lasers, monster Kineticstars and high performance "Space ICBMs" to blast incoming objects but colonies have to use their resources to get established and close the ecosystem; if they really need to take military action against Earth they will of necessity engage in an insurgency.
This is a real environment for pretty dramatic story telling, and probably a trope to be mined for all its worth.
I wouldn't think you'd have independent nations anywhere else but Earth, not for the next 2-300 years. Battles would be highly localizedto orbitals and fought by forces on hand.
Just Say No To Opera
Question for those in the audience (or the author, for that matter) who know a fair amount about age-of-sail shipbuilding: were there any significant technical advances in the eighteenth century which made trans-Atlantic shipping (and thus immigration) cheaper? Or was it just a matter of greater demand (colonization imperatives, cheap land, exile, etc)?
Re: Raymond
There were incremental increases in size for all gun ratings. But HMS Victory for example, was 40 years old at Trafalgar, meaning there hadn't been anything breathtaking since the 1760s. The most common type in the Napoleonic wars, the "74", was an innovation in the 1740s, but old hat by the turn of the century.
Tony:
I wasn't limiting the question to warships (although that info is helpful, thanks). I was wondering if the tech of the ships themselves in the seventeenth century would've supported immigration levels to North America like we saw in the mid- to late-eighteenth century, or if there was an advance which enabled ships to be lighter/cheaper/faster/safer/whatever.
Tony:
"First of all, that's not hard -- rendezvous is in the class of hard to achieve maneuvers when it's an actual mission objective and both spacecraft cooperate."
It's in the class of hard to achieve maneuvers when you want to match speeds and gracefully touch each other's docking ports safely. If you just want to ram something at high speed? A little easier, methinks.
Rick:
"On Ferrell's point, I would add that there is a huge contextual difference between warfare in Earth orbital space and space warfare anywhere else."
There is also a huge contextual difference between warfare in Earth orbital space because the US is invading China, and warfare in Earth orbital space because Mars is invading Earth (and we chose to not perform a deep space intercept).
"There are near-space assets, such as spysats, that highly relevant to conflicts between terrestrial great powers."
We can hit those with missiles from the ground. There is no way that this will be enough to lead to actual space-to-space warfare.
"Warfare in deep space (in the inclusive sense, not just 'the middle of nowhere')"
I'm not fond of any definition of "deep space" that includes the surface of Mars.
"In a perverse way, the more peaceful relations are on Earth in the next couple of hundred years, the more credible subsequent space-centric conflicts become."
I can actually see how this makes sense, if only because minor powers making war on each other without superpowers immediately coming along and quashing them is easier if the superpowers (which aren't likely to go away soon) are just too complacent to bother.
But even if Earth is heavily militarized, it can be they just don't care about Tethys attacking Dione.
Tony:
"The problem with using auxiliary spacecraft as guided missiles is that they're not euqipped with guidance sensors and navigation computers. One would have to sacrifice existing sensors and computer hardware built for these purposes, but you get no more than those already existing on the spacecraft you need for launch, and that you don't want to disable anyway."
If you knew you were going to use this tactic before you launched the spaceship (or at least before its last resupply mission), then you can load some additional sensors and microchips into your cargo.
But you're right that rigging sensors onto a spaceship backpack sounds nontrivial.
I was really thinking more of using stuff like satellite launch vehicles (which, I'll note, may be smaller and cheaper on worlds with gravity lower than Earth's, which is all of them).
"WRT PMF warfare, I think the most likely places for it to first occur will be in the orbitals wherever more than one power has an interest."
Orbitals? As in, space stations? I don't expect any space stations in the plausible midfuture to have the clout to count as political entities, or even to contribute significantly to their parent superpower's military might. You don't go to war against an oil rig.
If an orbital tries to rebel against its parent government, then you just stop supply shipments. Morons.
The real problem is that why would two Earth powers be willing to attack each other in space (and attack each other's forces directly, not with proxy wars) but not be willing to attack each other on the surface? Because if you can attack each other on the surface, then fighting to disable the enemy's spaceports so they can't launch any space missions is bound to be easier than building space warships to fight them in orbit. Yes, capturing a spaceport deep inside an enemy country is nontrivial, but is still strikes me as more cost-efficient than orbital war. Furthermore, if you do have orbital and surface wars side-by-side, then that means you now have to worry about combined arms tactics rather than treating space war in isolation.
Thucydides:
"The only real issue I can see that would draw people in this direction (or different approaches to the same solution) is the defense of Earth against space impacts."
The thing is that this is a peaceful mission, and deflecting asteroids is bound to be easier and cheaper if you don't worry about designing your spaceships to get shot at by those asteroids.
While a fleet of asteroid deflection ships might be a little easier to jury-rig for improvised military use than the average civilian spaceship, this in itself would neither require building weapons nor justify using them.
Also just having an asteroid deflection fleet doesn't mean you can slag other planets. Deflecting an asteroid just requires shifting its orbit by enough that it'll miss your planet, and does not require anywhere near the effort to make an asteroid hit a planet that it wasn't originally going to pass near.
Raymond:
I wasn't limiting the question to warships (although that info is helpful, thanks). I was wondering if the tech of the ships themselves in the seventeenth century would've supported immigration levels to North America like we saw in the mid- to late-eighteenth century, or if there was an advance which enabled ships to be lighter/cheaper/faster/safer/whatever.
You're right, I should have read more carefully.
Ships in both the India and America trades were everything from brigs to full rigged ships, but the relatively low volume, point-to-point nature of trade and limitations on private capital resources constrained them to being no larger than naval frigates in size. In fact, John Paul Jones's Bonhomme Richard was an old East Indiaman converted to a frigate. To give you an idea of the relationship between merchants and warships, the largest ever built were on a par for displacement and contemporary with the USS Constitution.
Also, merchant ships were built as cheaply as possible and sized to the expected market at time of completion. People complain today about expendable rockets, but in the beginning of the Indies trade, for example, it was considered a success if a ship came back from it's first voyage, and a cash cow if it completed more than one round trip. Over time more service was expected out of ships on the average, but even a few voyages to the East could make a ship a fully satisfactory and profitable adventure. The Atlantic trade routes had similar mathematics associated with them -- brand new, crack ships were expected to manage only four or five years of voyages on the average before being sold off to less flush operators on secondary routes, hulking, or outright scrapping.
WRT market sizing, the early 17th Century East Indiamen could be as much as 1200 tons, but over time, as competition got heavier and route knowledge got better, smaller ships were considered optimum. But over the course of the 18th Century, the ships did get larger as variety and volume of trade improved.
About three or four replies that I was intending to make have been rendered unnecessary because someone already made them.
'Deep space' does include the surface of Mars in the (important!) sense that getting there from Earth involves a deep space mission. There is no really graceful way, in current usage, to make some useful distinctions involving space settings and space missions.
Generally I agree with Tony that space armadas and interplanetary / interstellar wars are operatic tropes that are no part of what I have dubbed the plausible midfuture. Though we presumably (but not inevitably) would pass through the PMF to get to an operatic far future.
Sailing ships, both mercantile and naval, improved gradually and incrementally from the 16th century to the mid-19th century. It would be hard to quantify the degree of improvement. But I would say that the increased pace of emigration to the New World had more to do with population growth, general economic integration, and the like.
Or maybe a still better way to put it is that the gradual progress in sailing ships was an integral part of that larger process. What Adam Smith called 'improvement.'
Note that Smith had essentially no conception of the Industrial Revolution as we understand it - he only mentions the steam engine once, in a footnote.
Rick:
"'Deep space' does include the surface of Mars in the (important!) sense that getting there from Earth involves a deep space mission."
Not if colonists already live on Mars before the war breaks out.
And if they don't then why are you fighting on Mars at all?
Would you call a land battle in the American Civil War a naval battle because the participants were the decendants of trans-Atlantic immigrants?
"There is no really graceful way, in current usage, to make some useful distinctions involving space settings and space missions."
"Extraterrestrial."
Rick:
" But I would say that the increased pace of emigration to the New World had more to do with population growth, general economic integration, and the like."
Essentially correct, from what I have read. More ships for the emmigration trade were built or repurposed, but their technology didn't drive demand. It's interesting to note that this was a dynamic that extended well into the steam age. Titanic and her sisters were as large as they were not only because they could be made that large, but because the demands of the immigrant trade meant that a 1000+ passenger 3rd Class could be filled every two weeks for the trip westward. The immigrant traffic was actually considered the underlying revenue base for the ships when their construction was planned.
It seems to me that the two most likely scenerios for space warfare in the PMF would be either some conflict between two or more off-world outposts getting completely out of control; or, war in Earth orbit being just another theater of combat in a war between two or more Earth nations.
In the PMF, perhaps most 'combat' spacecraft would be just a specialized mission module you mate to a 'core' spacecraft. Of course, if there is some sort of arms race in space, then there might well be battle fleets in space...but I don't really expect that kind of future.
Ferrell
Milo
Asteroid deflection via gravity tractor or towing asteroids with flocks of solar sails would be possible, but not militarily useful.
OTOH if detecting asteroids is difficult and they only show up at close range (especially small asteroids) then something that can respond rapidly is needed. "Space ICBMs" have been proposed, essentially stripped down ORION nuclear pulse missiles capable of accelerating at 100 g and covering million of kilometers in a mater of hours. They will impact a target with a gigaton of kinetic energy, which might not be the best way to deflect an asteroid but will do in an emergency.
High power lasers will also serve, vaporizing material from the asteroid and creating a small but steady rocket effect to move the asteroid's orbit. Shooting an asteroid should not raise as many objections as the military laserstar firing at small military targets.
These technologies do have military potential, which is why I suggested they would form the basis of any space navy or military force.
Thucydides:
"OTOH if detecting asteroids is difficult and they only show up at close range (especially small asteroids)"
Small asteroids burn up in the atmosphere and pose no threat. Even if they survive reentry, they might not have enough speed left to pose a threat. (There was in fact someone who survived a meteor falling on her head with nothing more than a bruise. That's gotta be a cool story to tell your friends!)
Satellites in orbit are more vulnerable, but it doesn't seem worth it having such excessive asteroid deflection mechanisms just to protect some satellites. It's cheaper to just spend your money on replacing a satellite on the million-to-one chance that one actually gets hit, rather than spending it on launching a large fleet of asteroid deflection ships that you still can't guarantee will work.
The protection of crewed ships or space stations in orbit is the one thing that might justify extreme asteroid paranoia. But I still don't think this is an efficient solution. Actually, the best way for a space station to survive an asteroid that it sees coming is to simply perform a slight course adjustment so the asteroid misses it. The ISS already makes occasional orbit adjustments to avoid orbital debris now, so we know we can do it.
Basically, any asteroid that's difficult to detect simply isn't worth your time.
"million of kilometers in a mater of hours"
I suppose you weren't listening the last two times I challenged the plausibility of those numbers. Recently.
Milo:
http://nextbigfuture.com/2009/02/unmanned-sprint-start-for-nuclear-orion.html
"Nuclear explosive propelled Interceptor for deflecting objects on collision course with Earth. Johndale Solem, Los Alamos, proposed unmanned vehicle. No shock absorber or shielding. The pulse units were 25kg bombs of 2.5 kiloton yield.
Get to high velocities with only a few explosives and small shock absorbers or no shocks at all. Launch against a 100 meter chondritic asteroid coming at 25 km/sec. 1000 megatons if it hits. Launch when it is 15 million kilometers away and try to cause 10000km deflection. A minimal Orion weighing 3.3 tons with no warhead would do the job. 115 charges with a total of 288 kiloton yield. Launch to intercept in 5 hours. Ample time to launch a second if the first failed."
Since we currently have very poor coverage for incoming asteroids or NEOs, especially anything coming from the sunward direction, we do need a rapid response capability. If the object is very large we need to provide a great deal of energy for deflection. ORION interceptors provide both.
Thucydides:
"'Nuclear explosive propelled Interceptor for deflecting objects on collision course with Earth. Johndale Solem, Los Alamos, proposed unmanned vehicle. No shock absorber or shielding. The pulse units were 25kg bombs of 2.5 kiloton yield.
Get to high velocities with only a few explosives and small shock absorbers or no shocks at all. Launch against a 100 meter chondritic asteroid coming at 25 km/sec. 1000 megatons if it hits. Launch when it is 15 million kilometers away and try to cause 10000km deflection. A minimal Orion weighing 3.3 tons with no warhead would do the job. 115 charges with a total of 288 kiloton yield. Launch to intercept in 5 hours. Ample time to launch a second if the first failed.'
Since we currently have very poor coverage for incoming asteroids or NEOs, especially anything coming from the sunward direction, we do need a rapid response capability. If the object is very large we need to provide a great deal of energy for deflection. ORION interceptors provide both."
More reason to Just Say No to NBF. A 100 m chondritic meteor would most likley explode in the atmosphere above an ocean or uninhabited land. Even a nickel-iron meteor that penetrates the atmosphere to the surface wouldn't do all that much damage.
Tony said:"More reason to Just Say No to NBF. A 100 m chondritic meteor would most likley explode in the atmosphere above an ocean or uninhabited land. Even a nickel-iron meteor that penetrates the atmosphere to the surface wouldn't do all that much damage."
While I agree with most of everything you say in this comment, Meteor Crater was formed by the impact of a 50 meter wide Nickel-Iron asteroid. So, having a couple of asteroid interceptor/deflectors hanging out in orbit (maybe doubling as observitories) might be prudent.
Ferrell
Ferrell:
"While I agree with most of everything you say in this comment, Meteor Crater was formed by the impact of a 50 meter wide Nickel-Iron asteroid. So, having a couple of asteroid interceptor/deflectors hanging out in orbit (maybe doubling as observitories) might be prudent."
I was specifically thinking of Meteor Crater. We've made bigger, though shallower, craters during fusion weapon experiments. For example, Elugelab Island, which doesn't exist any more, thanks to Ivy Mike.
Would you call a land battle in the American Civil War a naval battle because the participants were the decendants of trans-Atlantic immigrants?
No, but a Brit or European would correctly call it an overseas battle. 'Deep space' has a few different shades of meaning, one of which is simply 'far from Earth.' In other contexts it means flat space, far from any large body.
I would guess that so long as there's no highly profitable or strategic McGuffinite, there won't even be significant spillover of terrestrial wars into deep space, just as Antarctica was not even a tertiary theater of operations in the world wars.
Deflecting a potential Earth-colliding asteroid or comet is essentially a civil engineering project. Even if it involves 'blasting,' it has no particular similarity to military operations, and does not lead to a military capability.
As an analogy, we have demonstrated the technical capability to drop stuff onto Titan, but it would be frivolous to say that we therefore have a military capability to bomb Titan.
Rick:
"...just as Antarctica was not even a tertiary theater of operations in the world wars."
But the Arctic did see some military action, when the Allies sent expeditions to capture the crews of German weather stations. The analogy with ASAT warfare in a future war should be obvious, even if such a future campaign would most likely be undetaken by robotic weapons.
"As an analogy, we have demonstrated the technical capability to drop stuff onto Titan, but it would be frivolous to say that we therefore have a military capability to bomb Titan."
I wouldn't go that far. With nuclear weapons, being able to deliver a package of a relatively small mass is almost all the way to being able to bomb a target. Replace the science/commercial payload with a nuke, add a few penetrations aids, and you're in business. Even with our relatively weak, non-operatic propulsion systems, being able to deliver a few hundred kilograms of copper slug to the target, without caring about a soft landing, well, we all saw what that could do, thanks to the Deep Impact mission.
I think it still be easier for the future Asteroid Defense force to invest in better detection capability, to see asteroid further away, and earlier, than to develop an Orion interceptor for when we see it too late.
Its cheaper, doesn't include the N-word, and is a direct development from current satellite placement technology.
We can then invest, in again, cheaper, non-N options such as sending forward a refocusing lens to direct a beam to the asteroid's surface, or place a solar-electric booster that slowly diverts the asteroid while using the rock as propellant in the process.
Too bad that a 50 microarcsecond detector only finds the asteroid around 100 thousand km from earth, in other words, lasing will be inefficient due to beam wandering and accuracy problems.
Ferrel- It seems to be that an easily directed jet of nuclear flame, otherwise used for propulsion, is an effective close-in defence system. We're expelling these sub-kiloton charges several times a second; why not sacrifice a few to blast the incoming kinetics. At 100km jet collimation, 80km/s incoming speed, you'll have just enough time to target the incoming kinetics and blast away, meaning you'll have ratio of one propulsive charge per incoming missile vaporized, but its worth it if the other option is getting the ship slagged.
This might balance the equation more favourably to the defender's side, with Casaba howitzers being trailed on wires for a rag-tag last line of defense. Otherwise 50 tons of kinetics suffice to slag an opposing accelstar (in a formal, fixed range, numerical parity fight), bad economically.
Also, what happens to kinetics in the last 100km to target. You might be able to blast through kilometer's per second of armor, but can you target the main mirror at zippy incoming kinetics from that close?
Tony:
"We've made bigger, though shallower, craters during fusion weapon experiments."
Meaning that craters that size pose negligible climate threat. They could still be quite deadly if they happen to hit a city - although all you need to do to prevent that is deflect it just enough that it hits somewhere else instead (ocean would be easiest and safest), not so much that it misses the planet entirely.
Rick:
"No, but a Brit or European would correctly call it an overseas battle. 'Deep space' has a few different shades of meaning, one of which is simply 'far from Earth.'"
..."Overspace"? That doesn't sound right.
Anyway, as they say, once you're in orbit, you're halfway to anywhere. (At least if you don't mind really slow trips, which we currently don't with robotic missions.) So I don't see the point of a term that considers high Earth orbit or even low Earth orbit (which isn't easy to reach) "nearby", but Mars "far away".
"As an analogy, we have demonstrated the technical capability to drop stuff onto Titan, but it would be frivolous to say that we therefore have a military capability to bomb Titan."
Actually, it would be very easy for us to bomb Titan, as long as we're willing to wait a decade before one small payload goes boom over a small area, and we aren't worrying about any defenders on Titan shooting to intercept our bomb.
These conditions would probably not apply in a real war.
Milo:
"Meaning that craters that size pose negligible climate threat. They could still be quite deadly if they happen to hit a city - although all you need to do to prevent that is deflect it just enough that it hits somewhere else instead (ocean would be easiest and safest), not so much that it misses the planet entirely."
If you want to invest in deflection, having it miss the planet is probably the only worthy goal. But my point was not about the environmental disaster potential of an impactor in the 100 m range, but the likelihood that it wouldn't be that likely to hurt many, if any, people. As overpopulated as we seem to think the planet is, in reality it's still got a lot of empty space to absorb random darts thrown its way.
"Anyway, as they say, once you're in orbit, you're halfway to anywhere. (At least if you don't mind really slow trips, which we currently don't with robotic missions.) So I don't see the point of a term that considers high Earth orbit or even low Earth orbit (which isn't easy to reach) "nearby", but Mars "far away"."
The element of time plays an important role in human perceptions of distance. I used to commute 30 miles in a certain direction to work, then I commuted 30 miles in the other direction. In the first case, it was against traffic, so work seemed relatively closer than it did when I went the other way.
But there's a real engineering dimension to this. With manned craft, at least, it's a lot more effort to send x number of people to Mars, because you have to send supplies for a couple of years along with them. That's a larger spacecraft that also has to be more robust and reliable, because the mission is longer and bailout is problematic. A trip to LEO or even GEO is not so big a production, because you can have supplies for as little as a few days, plus safety margins, and bailout is just a retro burn away.
Milo -
(At least if you don't mind really slow trips, which we currently don't with robotic missions.) So I don't see the point of a term that considers high Earth orbit or even low Earth orbit (which isn't easy to reach) "nearby", but Mars "far away".
For human missions, travel time and additional delta v make a big difference - we've sent 500+ people to LEO, a dozen to the Moon, none anywhere else.
And in tactical terms there's an important difference between space with lots of 'stuff' - including a planet - within a few hours' flight time, and space well away from such clutter.
These conditions would probably not apply in a real war.
That is more or less what I hand in mind. A civil demolition team has more differences than similarities to a military demolitions unit, and diverting an Earth-threatening asteroid does not really call for creation of anything like a 'space force.'
Tony:
"As overpopulated as we seem to think the planet is, in reality it's still got a lot of empty space to absorb random darts thrown its way."
Yes, if you just drop a city-size explosion at random, there's only a million-to-one chance of it actually hitting anything important. But there's also only a million-to-one chance of us getting threatened by an asteroid large enough to cause a global climate hazard anytime within the next few thousand years. If we're worried about asteroid deflection at all, it's because we want to pay attention to million-to-one chances.
Rick:
"And in tactical terms there's an important difference between space with lots of 'stuff' - including a planet - within a few hours' flight time, and space well away from such clutter."
Which goes back to the definition of "deep space" that doesn't include a rocky plain on the surface of Mars.
Mars's orbit already has some clutter (probes we've sent over the years), and will undoubtably have more by the time anyone starts fighting there.
Sine there is a desire to create a space force to fight space wars; and asteroid intercept force seems to be as close as we are going to get to a logical starting point.
While adapting space probes for military purposes (bombing Titan) is a bit outlandish, I recall it works the other way around. The Pioneer Venus Multiprobe used MIRV ICBM technology to accurately deliver several probes from the spacecraft bus back in 1978.
KraKon: yes, the Casaba-howitzer does seem like a short-to-point-blank range weapon. I always imagined that the Casaba-howitzer was more like a mortor than a proper cannon; your comment about having the charges on wires made me think about TOW missiles; maybe we should think about the Casaba-howitzer as a TOW from hell...:0
I just thought about this: what if the first 'space' war was a land battle between two off-world colonies?
Mars, the ancient lakebed between two outposts:
"Damn it, Professor Peabody! I need to dig here for aluminum! My colony needs it for our new green house! So, get lost!"
"Mr. Gordon! This site is the most likely to hold Martian Fossiles! If you dig here, all will be lost!"
"Yer a loon! get lost!" Pushes the other man down.
"Ow! Damn you, you will rue the day!"
"Yeah, right..."
A few days later, at the dig site.
"Hey, Mr. Gordon! Over there, that group of people. Isn't that that crazy scientist from over the hill?"
"Yeah...what the hell does he have? Oh, crap! It's a rocket! Run!"
And before anyone thinks that this is implausible, the U.S. and Canada once had a day-long war over a pig...
Ferrell
"I always imagined that the Casaba-howitzer was more like a mortor than a proper cannon; your comment about having the charges on wires made me think about TOW missiles; maybe we should think about the Casaba-howitzer as a TOW from hell...:0"
There's already a Hellfire missile in existence!
What I meant was that Casaba-Howitzers are designed for propulsion, their destructive side effects are, well, side effects. Not being deigned to be a weapon from the beginning, the crew would have to jerry-rig some contraption to use that nuclear jet of flame as a defensive weapon.
What I came up with was attaching the charge to a wire, and spinning it around. That would keep at least a few charges where you want them to be (facing the incoming missile once in range) all while removing the necessity of installing miniature thrusters onto each charge to align it with the enemy. Cheap, simple, and something a tele-operated waldo can do...
"I just thought about this: what if the first 'space' war was a land battle between two off-world colonies? "
That's for certain. I saw it as a confrontation between armed police forces and colonists a bit further out from the central dome that decide to organize a defense. Cop kills a colonist of opposing mob, mob moves in and smashes and pillages a few outposts. Then the central dome's parent country decides to send in the troopers, with their railguns and combat armor...Until now its only been police action, perfectly legitimate. But, having a dead colonist is enough of a motive for nation B, who has a grudge against nation A, to install a blockade of all incoming ships from the central colony.
End result? We have ground troops shooting at each other, an international diplomatic crisis, an orbital blockade, and a laserstar sent off to Mars to tell the blockading ships to move it. WARR!
While the day long war over a pig is much more likely than above, you have to think big, and escalate from there to have a real space war. Gordon and Peabody are arrested, end of story. Gordon and Peabody sabotage each other's domes with demolition charges, killing a few hundred, and you've got a crisis. If THAT escalates to war, it's all political.
What are the advatages and disadvantages of engaging in military action? The cost of sending a laserstar/supplying blockaders vs standing your ground against the Imperialists?
"Since there is a desire to create a space force to fight space wars; and asteroid intercept force seems to be as close as we are going to get to a logical starting point"
This would be the start point of a deep space force, one that can extend its power over interplanetary ranges. This is unlikely to be the first priority. I see warships as evolving from otherwise normal nuclear shuttles and Earth/Mars supply ships, but then you bolt on a gun on it. Instant warhsip. Weapons then evolve to need hard, incorporated-since-launch mounts. As the efficiency of the weapon system is increased, we start building dedicated combat ships, for orbital use.
It's unlikely a long range probe designed to set up a focusing lens past Mars orbit will evolve into a warship the other way round (from small to big, from long distance to orbital space).
KraKon said:"There's already a Hellfire missile in existence!
What I meant was that Casaba-Howitzers are designed for propulsion, their destructive side effects are, well, side effects. Not being deigned to be a weapon from the beginning, the crew would have to jerry-rig some contraption to use that nuclear jet of flame as a defensive weapon.
What I came up with was attaching the charge to a wire, and spinning it around. That would keep at least a few charges where you want them to be (facing the incoming missile once in range) all while removing the necessity of installing miniature thrusters onto each charge to align it with the enemy. Cheap, simple, and something a tele-operated waldo can do..."
Ok, I think I know what's happened; you are confused by the different terms. The 1950's Orion Pulsed Nuclear spacecraft and the Casaba-Howitzer both use nuclear pulse units; however, these pulse units are mostly identical with the exception of some targeting and positioning equipment, but mostly for the faceplate; in the propulsion pulse unit, the faceplace is thick, wide, and made of a heavy element; in the Casaba-Howitzer the pulse unit's faceplace is thin, not so wide, and made of a light element. The Casaba-Howitzer is a spealized launcher; it shoots a pulse unit in the general direction of a target and it lines up with that target; it fires after it gets several thousand yards away (about a mile or a couple of kilometers). The concept of the Casaba-Howitzer has been around since the early 1960s, just a little less than the Orion spaceship and the Excaliber bomb-pumped X-ray laser. There is still a lot of information about those weapons programs are still classified. Try looking up the information on the Atomic Rockets website, the Popular Science website, the General Atomics website, and websites about William Tellar for more information about the subject. I hope that helps.
Ferrell
I'd guess that the first deep space (meaning interplanetary/interstellar) 'warships' would be ordinary passenger transports that happen to be carrying troops.
The next step after that would be jury-rigged kinetics, or else weapons designed for Earth orbital use, and repurposed.
Once you start sending troops, you have to worry about your troopships being blown up in transit by small civilian spacecraft jury-rigged into missiles. In order to successfully perform an interplanetary invasion against an enemy with any significant industrial capacity, you will need point defenses to keep your troopships safe. After that, your enemy needs to worry about how to get through your point defenses.
Milo said:"In order to successfully perform an interplanetary invasion against an enemy with any significant industrial capacity, you will need point defenses to keep your troopships safe."
I'd add at least one ship that had surface bombardment capabilities to support your ground troopers.
Ferrell
Since there seems to be some confusion or disagreement about what "deep space" should mean, can I toss out a couple suggested alternative terms to use instead?
Far space: Any part of the universe beyond the neighborhood of the Earth-Moon system. This term includes the surfaces, and even the interiors, of any other planets. Very much an Earth-centric term.
Flat space: Space that is not in the neighborhood of any other planet (or star). We've already been using this term to mean pretty much this. "Flat space" is a subset of "far space."
And we can just avoid using the confusing/contentious term "deep space" (even though I love the sound of it).
The term "neighborhood" is undefined at the moment. Maybe it means "Hill sphere."
Stevo Darkly said:"And we can just avoid using the confusing/contentious term "deep space" (even though I love the sound of it)."
How about we use 'Far Space" as stated, but only in regardes to our Solar System and 'Deep Space' to mean the same thing, just some other star system? or interstellar space?
Ferrell
I always thought the taxonomy was:
1. Orbital space, designated by various names, all explicit about their orbital nature. (LEO, GEO, lunar orbit, [x planet] orbit, etc.)
2. "Deep space", meaning relatively flat space between planets.
3. "Interstellar space", meaning really flat space between stars.
4. "intergalactic space", meaning really, really flat space between galaxies.
I also like the term 'deep space' (obviously!), and so far as I can tell it is already the standard term, at NASA, etc., for 'anywhere far from Earth.' That is, for what Stevo Darkly offered 'far space.'
The underlying problem is that, for discussions here, we need terms that distinguish the strategic and tactical properties of various regions of space.
For example, when I speak of 'orbital space,' I usually am implicitly thinking of the zone close enough to a planet that orbital periods are in hours, gravitational acceleration is a significant fraction of a g, and the planet's bulk fills a significant chunk of sky.
Similarly, for the - common - situation in which an FTL system a) requires a longish normal space trip to and from planets, and b) is mostly offstage so far as combat is concerned, 'interplanetary' and 'interstellar' are nearly synonymous in military terms.
I'm a bit reluctant to define an elaborate vocabulary for this blog, since it would differ from usage everywhere else.
Ferrell:
"I'd add at least one ship that had surface bombardment capabilities to support your ground troopers."
Although this is something that a serious arms race will quickly produce, it isn't a strict requirement for attempting an invasion. If the defenders are civilians trying to resist you with jury-rigged equipment and police-issue weapons, then you may not need orbital bombardment for your troops to be able to overcome the locals, but you do still need enough point defenses to be able to safely land those troops. (Once they're landed, using improvised weapons against them becomes much more difficult - there's IEDs, of course, but the clutter of ground combat prevents you from killing a huge amount of troops in one go with anything.)
Stevo Darkly:
"Far space: Any part of the universe beyond the neighborhood of the Earth-Moon system. This term includes the surfaces, and even the interiors, of any other planets. Very much an Earth-centric term."
If you want to be a little less parochial, you can say "any part of the universe beyond the planetary system of the speaker's current location/homeworld". Just coincidentially means the same thing for everyone I've met so far...
Just like Americans consider Europe to be "overseas".
Tony:
"I always thought the taxonomy was:
1. Orbital space, designated by various names, all explicit about their orbital nature. (LEO, GEO, lunar orbit, [x planet] orbit, etc.)
2. "Deep space", meaning relatively flat space between planets.
3. "Interstellar space", meaning really flat space between stars.
4. "Intergalactic space", meaning really, really flat space between galaxies."
Well yeah, you can use that as a scale of progressively deeper space. Except if I'm bothering with that scale I'd call your #2 "interplanetary space" for full explicitness and nomenclature consistency.
You can also consider another level of orbital space where you're affected by the gravity of both a planet and a moon, but that might be a little pedantic.
I guess I really consider "deep space" to be synonymous with "flat space", in the sense that it includes everything from your #2 up... it's just that #2 is the flattest you're likely to ever be without FTL technology, which prevents using known laws of motion anyway. Thus, whenever I'm talking about deep space as it applies to rocketpunk technology, I'm talking about interplanetary space.
Stevo Darkly:
"confusing/contentious term "deep space" (even though I love the sound of it)."
Rick:
"I also like the term 'deep space' (obviously!)"
Count me in.
"Flat space" just doesn't have the same intuitively obvious "very far away from anything that matters" connotation that "deep space" does.
Rick:
"For example, when I speak of 'orbital space,' I usually am implicitly thinking of the zone close enough to a planet that orbital periods are in hours,"
Well, geosynchronous orbit - which is a reasonable upper limit to what you consider to be "hours", and which we'll really want to include because it has important economical and tactical relevance - is some 42000 km above the center or 36000 km above the surface, which is 10% of Luna's distance.
"gravitational acceleration is a significant fraction of a g,"
At Earth's Hill sphere, gravity is 18 microgee, which is probably not "significant".
At one lightsecond (roughly lunar distance), Earth gravity is 452 microgee, so probably still not all that "significant".
At geosynchronous altitude, gravity is 2.3% gee, which is... getting there? I'd count it. That's more than the gravity on Mimas's surface, for one.
"and the planet's bulk fills a significant chunk of sky."
Well, the full earth should look larger from the moon than the full moon looks from the earth (duh!), so the distance you described reaches out to at least 1/5th of Earth's Hill sphere.
At the very edge of its Hill sphere, Earth has an angular diameter of 29 arcminutes. Which, by an amusing coincidence, is only very slightly smaller than the sun or moon as seen from the earth (and, as a corollary, the sun as seen from the edge of the earth's Hill sphere).
At the edge of its Hill sphere, Saturn has an angular diameter of 6 arcminutes. (The lower density of a gas giant raises its angular diameter, but the increased distance from the sun countermands that.) This isn't very large, but it's still 20% of the full moon.
So size shouldn't really be a concern.
I guess the real point is that the zone between low orbit and the Hill radius covers a wide range of operational conditions. The inner portion of that zone is dramatically different from the outer portion.
And where you draw what lines depends heavily on details of technology.
I've said before that from a military perspective, "low orbit" is "anything in range of surface-to-orbit defenses", and "high orbit" is "anything not in range of surface-to-orbit defenses".
Realistically, people will be all over the place with terminology. Esecially with the laymen, we'll have maddening imprecision. I do happen to like the following terms:
1. Sphere -- denoting space important something. You have the Earth Sphere pertaining to Earth though some people might call it the Earth-Luna Sphere, the Jovian Sphere for everything related to Jupiter. The Solar Sphere would then encompass the entire solar system. Would contain connotations both political and geographical (astrographical?)
2. Deep Space -- would be more informal, colloquially implying that rescue becomes more complicated. Analogous to the implied difference in danger when talking about intracoastal waters and open waters. Could be taken as a lubbardly term used by dirtsiders and later ironically embraced by spacers similar to the way computer geeks would start using "wrong" names for the internet such as the interweb, the tubes, etc.
3. Interplanetary space -- more technical, outside of planetary spheres of influence, nominally the Hill sphere but in practical terms whatever the "territorial waters" or exclusion zone of the polity are claimed to be. If Earth is real particular about safety, the sphere could be light minutes out.
4. Interstellar space -- I'd stick the boundary here at the heliopause or possibly the equivalent of the hill sphere for scattered disk objects. Where the gravitational influence of passing stars is of greater significance than the influence of the primary. But again, the political definition could be greater.
A random observation that occured to me, apropos of nothing, is that there is one unreconcilable gap in the space=water analogy: there is no space-based equivalent of an inland lake.
Jollyreaper:
"If Earth is real particular about safety, the sphere could be light minutes out."
Mars is only 4.355 lightminutes from Earth at closest approach, and Venus (less likely to have a colony) is only 2.3 lightminutes. So any sphere of influence nearing those numbers is likely to step on someone's toes.
Of course, in early stages of colonization Earth can expect to remain the biggest power in the solar system, which means that its governments may well claim the right to control large swaths of interplanetary space not by virtue of being the Lords of Earth, but by virtue of being the Lords of Sol. (But they might still do this with Earth's safety in mind. Since when have imperial lords ever put their colonies' best interests at the forefront of their mind?)
"or possibly the equivalent of the hill sphere for scattered disk objects. Where the gravitational influence of passing stars is of greater significance than the influence of the primary."
The problem is that while stars can be loosely said to orbit around the galactic core, the core itself doesn't actually mass that much. Rather stars orbit around their shared center of mass, which exert a lot of gravity in concert, but not all that much individually.
Thus a star's "Hill sphere" would probably just end up meaning "halfway to the next star" (assuming the next star is of similar size), since wherever you are, either one star's gravity has a bigger pull on you or the other does. This doesn't feel right. There should be some "interstellar space" between one star's sphere and another's.
"But again, the political definition could be greater."
If you have jump, wormhole, or hyperspace FTL, then there may well be no political definition of interstellar space - no-one passes through it, so it doesn't matter.
Milo:
"Well yeah, you can use that as a scale of progressively deeper space. Except if I'm bothering with that scale I'd call your #2 "interplanetary space" for full explicitness and nomenclature consistency."
Well, the "inter[x]" nomenclature is actually quantitative, not qualitative. They describe the relative deepnesses of "deep". The only real qualitative terms are "near" (or "orbital") and "deep". And I'm okay with that. Why make things more complicated than they need to be?
Tony:
"The only real qualitative terms are "near" (or "orbital") and "deep"."
Well, I would interpret "near space" as "the orbital space of the planet we're on" - so, the opposite of far space - as opposed to any orbital space in general.
So how about:
- Outer space: Everything that's not directly on or in a planet/moon/etc. (Not sure about exact definition here. For planets with atmospheres, the turbopause is a good scientific place to but the boundary, but it's less obvious where to define outer space as beginning for bodies that have vacuum down to the surface.)
- Orbital space: Outer space within the Hill sphere of a planet.
- Deep space: Outer space not within the Hill sphere of a planet.
- Interplanetary space, interstellar space, etc.: More detailed subclasses of deep space, when extreme precision/formalism is called for.
- Near space: Anything within the Hill sphere the planet the speaker is on.
- Far space: Anything not within the Hill sphere of the planet the speaker is on, including stuff that wouldn't normally be considered "space" like the surfaces of other planets.
I would also suggest beyond the frakkin' ecliptic (BFE for short) to describe locations really far of the orbital plane.
jollyreaper:
"I would also suggest beyond the frakkin' ecliptic (BFE for short) to describe locations really far of the orbital plane."
Orbits very far off the system plane don't have a lot of value until you get into the interstellar setting, and maybe not even then. For example, if you have go-anywhere FTL drives, there's no real point in worrying about anyplace, in any star system, that isn't a body of interest. With manufactured wormholes/stargates, your interstellar access is going to be near planets, or at least within a few degrees of the system mean plane. Even with fixed natural jump points positioned significantly far from the ecpliptic, what you're really going to care about is a realitvely narrow cone defining the possible routes from the system plane to the jump point. See, everything revolves around bodies near the system plane.
Orbits very far off the system plane don't have a lot of value until you get into the interstellar setting, and maybe not even then. For example, if you have go-anywhere FTL drives, there's no real point in worrying about anyplace, in any star system, that isn't a body of interest. With manufactured wormholes/stargates, your interstellar access is going to be near planets, or at least within a few degrees of the system mean plane. Even with fixed natural jump points positioned significantly far from the ecpliptic, what you're really going to care about is a realitvely narrow cone defining the possible routes from the system plane to the jump point. See, everything revolves around bodies near the system plane.
That's exactly why anything beyond the frakkin' ecliptic would be said to be way out in BFE. :)
In terms of where anyone is going to be for military, political, economic or social reasons, we will probably see more emphasis on "places" we already know exist.
The five Lagrange points will feature prominently as the location of colonies, facilities and so on.
Surface, Low orbit, High orbit, Stationary orbit probably represent the areas of interest around a planet or large moon.
The Hill Sphere might be considered the "territorial limit", with deep space beyond reserved for the right of innocent passage by all space going nations or people.
Thucydides:
"The Hill Sphere might be considered the "territorial limit", with deep space beyond reserved for the right of innocent passage by all space going nations or people."
Only if the planet in question has a single, monolithic government. If it's Earth in the plausible midfuture, or any planet not under a single authority, national sovereignty stops at the limits of outer space, usually defined as the altitude at which a satellite can maintain an orbit with minimal propulsive effort.
Thinking about it, it seems to me that the fundimental difference between space and any other enviornment is that things are always in motion relitive to something or somewhere else, in an immedeately meaningful way to those people (or vehicles), traveling through this medium.
Ferrell
is that things are always in motion
Yes - note for example that there is no real equivalent to harbors in space, and stations are not essentially different from ships.
On orbital space, there is a reasonable distinction between low orbital space (within minutes' flight time of the surface) mid-orbital sspace (for Earth, roughly from a few hundred km out to geosynch), and outer orbital space, from there to the Hill radius.
But I hesitate to create formalized complications that will merely get debated!
Tony:
"outer space, usually defined as the altitude at which a satellite can maintain an orbit with minimal propulsive effort."
On an airless moon, you could in theory maintain a stable orbit directly above the surface. Of course, the surface isn't level so you'd have to stay above its highest point, and minor perturbrations could mess up your day at that altitude. But still, very low orbits are nonetheless possible (possibly even lower than some buildings or mountains right next to the orbital track), though one might ask why you would want to.
Mars, however, does have enough of an atmosphere to cause a major drag on satellites.
Anonymous said:"But still, very low orbits are nonetheless possible (possibly even lower than some buildings or mountains right next to the orbital track), though one might ask why you would want to."
To sneak up on an enemy; the same reason to fly nap-of-the-earth here on Terra, the element of suprise.
Ferrell
I think the only people being surprised by an NOE type orbit will be the ones on the spaceship in question......
Thucydides, I think that the people on the ground might be damned surprised to have a spacecraft zip over them at orbital velocity...but only until the anvil hits them in the head that the spacecraft drops on them.
Ferrell
I'm going to take my stab at definitions. Actually, I'll go farther, and make an attempt at a taxonomy of enviroments, along with what we might expect to see in each of them. These are not all going to focus on all-out warfare either. I'm mostly looking at enviroments that a spacecraft might be designed for. A given universe might see several of these as tactically relevant.
Byron's Taxonomy of Space Warfare:
I. Intraplanetary Warfare
Interplanetary warfare is between two or more powers on the same planet. In any setting like this, space warfare will be a sideshow to the rest of the war.
A. Sattelite Warfare
This is the current situation. Space war will be mostly about shooting down the other guy's sattelites, and it will be done from the ground (in the broadest sense). Humans in space will almost certainly be uninvolved directly in the war. There are no spacecraft shooting at each other.
B. Station Warfare
Activity in space has picked up significantly. Militarily significant human concentrations are in orbit. Warfare is still mostly ground-to-orbit, but there is likely to be some orbit-to-orbit warfare as well.
C. Cloistered Orbital Warfare
For whatever reason the earth-based powers aren't using surface-to-orbit weapons. I don't know why. Fighting is likely mostly done by short-range fighters, which leave stations, attack, and return to their carriers. Delta-V requirements are minimal.
D. Orbital Patrol
This is a non-combat situation. It favors fighters even more then IC. Inspections and boarding actions are far more common than battles. Delta-V is low, as are weapon powers. All-out warfare will probably result in IB, though IC is possible.
II. Intraorbital Warfare
Intraorbital warfare covers battles between powers in orbit around the same body when at least one power isn't on the body.
A. Surface to Station Warfare, Total
An orbital population is fighting with a surface population. This is most likely to involve the surface power shooting at the orbital power from the surface.
B. Surface to Station Warfare, Limited
This is similar to IIA, but it is far more likely to be space-to-space. If the surface power has limited goals, such as capturing the orbital population, kinetics alone are unlikely to work. It overlaps with IC and ID.
C. Station to Station Warfare
This is a battle between two space-based powers. It will likely resemble IIB.
D. Orbital Patrol
See ID.
(to be continued)
One thing that has occured to me during my thinking on my taxonomy is how likely space warfare is to be asymetrical. I mean that in the broadest sense. Except for Type I warfare, just about every scenario I can see occuring does not occur between equal powers. For example, take a IIC. Station A is trying to take over Station B. Station B doesn't want Station A, they just want to be left alone. They can use improvised kinetics against A's assault shuttles. A can't use kinetics becuase that would ruin what they are trying to attack.
Any form of interplanetary warfare must be asymetric. It is impossible to project enough force between planets to overwhelm a defender who is within an order of magnitude economically. Maybe several orders of magnitude.
Actually, I need to amend that. It is impossible to wage symetrical warfare with an equal opponent if your objective is anything but destruction. If you are just trying to destroy the opponent, then you can do so with an equal one. If your objective is anything else, then a large advantage is required. Actually, that describes modern warfare (in the age of nukes) fairly well, too.
Byron:
There are going to be spaceships for things other than warfare. Civilians are also going to need to worry about if they're in deep space or not, however you choose to define that. (The low orbit/high orbit split that I usually use, "low orbit is whatever's in range of surface-to-orbit defenses", does not directly apply to civilians, but it's close enough in spirit. Low orbit is stuff that's "easy" to get to with a rocket launch, high orbit is stuff that in practice usually requires a multi-stage trip including a transfer orbit.)
"ID. Orbital Patrol
This is a non-combat situation. It favors fighters even more than IC."
It favors patrol boats. Patrol boats need boarding crews (for inspection of suspicious travellers), which means you need more than the one or two crew members that fighters are typically seen having. Also unlike fighters, they will rarely if ever engage in combat against other vehicles of the same class. (Indeed, they will rarely engage in combat at all - their purpose is to wave their weapons around menacingly without actually firing them.)
"IIA. Surface to Station Warfare, Total
An orbital population is fighting with a surface population. This is most likely to involve the surface power shooting at the orbital power from the surface."
Do you perceive there being any chance of a station in a state of total war with the surface succeeding in winning its independence? I don't.
I am of the position that space stations are going to be like oil rigs - they're implicitly possessions of their parent nation, and it's absurd for one to even attempt to go to war. It's just kindasorta conceivable for one oil rig to invade another oil rig if the real governments aren't interested in asserting their dominance, but even then it seems rather unlikely.
Most drama on a space station is going to be internal intrigue, with no spacegoing vehicles involved.
"One thing that has occured to me during my thinking on my taxonomy is how likely space warfare is to be asymetrical."
The only way to have symmetrical (= operatic) space warfare is to have powers on separate worlds, for example Tellus vs Mars or Tellus vs Luna. Obviously, you need to colonize those places first.
But in our solar system it seems like even these will be at a disadvantage - even with advanced terraforming tech, a colony is likely to be more fragile (easier to revert to a location where humans cannot survive) than Earth itself. AND Earth has a head start in infrastructure construction (though this may not matter in the sufficiently distant future - the US overtook Europe economically), AND Earth is just plain bigger than anywhere else. But then again, if Mars has been colonized for a long time, there are any number of factors that might limit this - not so much removing Earth's advantages as countering them with even more disadvantages.
"It is impossible to project enough force between planets to overwhelm a defender who is within an order of magnitude economically."
This was more or less true in any time period. To fully conquer an enemy, you need a significant force advantage - though you may still be "symmetrical" in the sense of using a similar kind of force rather than needing to rely on guerilla tactics.
When two hostile powers are close in strength, they will engage in border skirmishes and the like, without attempting to strike at each others' homelands. Though border skirmishes can, again, be symmetrical.
Anyway, a small degree of asymmetry can be beneficial for operatic plots. Everyone likes the put-upon heroes' daring resistance against the evil empire - but they like it when those heroes use cool ships rather than suicide bombers. Having a small-medium nation (but still a real nation with a real military) resist an imperial invasion due to the force multiplier that comes with being on the defensive seems to fit the bill.
Milo:
There are going to be spaceships for things other than warfare.
I know. However, this is a taxonomy of space warfare.
It favors patrol boats.
I meant fighters in the broadest sense of the term, IE short-endurance manned craft. Patrol boats would fall under fighters.
Do you perceive there being any chance of a station in a state of total war with the surface succeeding in winning its independence? I don't.
I don't either. It just bore mentioning. However, I don't see that sort of total war as likely either.
The only way to have symmetrical (= operatic) space warfare is to have powers on separate worlds, for example Tellus vs Mars or Tellus vs Luna. Obviously, you need to colonize those places first.
I haven't gotten that far yet, but even then it will be asymmetrical, unless they go for the "kinetic duel to the death" option. Why? Because no other option can be fought symmetrically.
Take a look at World War II. Both sides had similar aims by the middle of the war. Conquer the other guy. I know that that's an oversimplification, but at some point, that was everybody's goal. And everyone used the same means to attempt that goal. This was because power projection was cheap enough to allow a country to spend most of it's money on soldiers and not on getting them there. If we're in an Honorverse-style setting (interplanetary shipment of bulk foodstuffs is economically viable), then that might be the case. However, in PMF, the projection of power will be a large part of the overall budget, giving the defender a huge advantage. Matched powers can't fight each other that way.
To fully conquer an enemy, you need a significant force advantage - though you may still be "symmetrical" in the sense of using a similar kind of force rather than needing to rely on guerilla tactics.
Yes, but I think that said advantage will need to be far more pronounced in space than on earth. The best scenario I can think of is one in which all forces and supplies must be airlifted into a combat zone. That's going to put a major crimp in your ability to operate compared with cheap naval transport.
When two hostile powers are close in strength, they will engage in border skirmishes and the like, without attempting to strike at each others' homelands. Though border skirmishes can, again, be symmetrical.
This is very true. Though I'm thinking that "border skirmish" will be a misnomer in space.
Byron:
"Take a look at World War II. Both sides had similar aims by the middle of the war. Conquer the other guy. I know that that's an oversimplification, but at some point, that was everybody's goal."
It's way more accurate to say that the two sides' war aims had been inverted by the middle of the war. The Allies started out just trying to survive, while the Axis was bent on conquest. By 1943 -- which is actually late in the war by some means of reckoning, but let's not get too pedantic -- The Allies were all about overwhelming the Axis states, while the Axis states were simply trying not to lose.
"And everyone used the same means to attempt that goal. This was because power projection was cheap enough to allow a country to spend most of it's money on soldiers and not on getting them there."
Power projection across the owrld's oceans was almost overwhelmingly expensive. That's why McNair's original plans for a wartime army of 200+ divisions was scaled back to less than 100. They could have been raised with US manpower, and equipped by US industry, but they couldn't have been transported to the battlefields with the resources that would have been left. And this was with an economy that by most measures commanded 50% of the planet's military applicable industrial resources. IOW, even with massive asymmetry, power projection was a daunting proposition.
"If we're in an Honorverse-style setting (interplanetary shipment of bulk foodstuffs is economically viable), then that might be the case. However, in PMF, the projection of power will be a large part of the overall budget, giving the defender a huge advantage. Matched powers can't fight each other that way."
Even in the Honorverse winning interstate warfare would have to be about winning naval victories and demanding defenseless planets surrender on pain of being nuked. Projecting armies over space, except for light infantry occupation MPs, would be prohibitively expensive.
Tony:
t's way more accurate to say that the two sides' war aims had been inverted by the middle of the war. The Allies started out just trying to survive, while the Axis was bent on conquest. By 1943 -- which is actually late in the war by some means of reckoning, but let's not get too pedantic -- The Allies were all about overwhelming the Axis states, while the Axis states were simply trying not to lose.
Point, but it doesn't really change the central thrust of my argument. Both sides were trying to conquer territory at some point. Symmetrical war aims will mean symmetrical war means.
Power projection across the owrld's oceans was almost overwhelmingly expensive. That's why McNair's original plans for a wartime army of 200+ divisions was scaled back to less than 100. They could have been raised with US manpower, and equipped by US industry, but they couldn't have been transported to the battlefields with the resources that would have been left. And this was with an economy that by most measures commanded 50% of the planet's military applicable industrial resources. IOW, even with massive asymmetry, power projection was a daunting proposition.
OK, but now raise the fraction of power required for projection tenfold. Suddenly, you need an even bigger overmatch.
I'm going to guess that to be able to do something like a blockade, you need an order of magnitude more economic power than your enemy. To be able to control their orbits (destroy their space forces and some ground-based defenses, while not worrying too much about low orbit) would take two. An invasion would probably take three or more.
Plus, I'm pretty sure that most of those extra divisions wouldn't have been ready in time to fight anyway.
Even in the Honorverse winning interstate warfare would have to be about winning naval victories and demanding defenseless planets surrender on pain of being nuked. Projecting armies over space, except for light infantry occupation MPs, would be prohibitively expensive.
Yes. This reminds me of something. Say, my arguments in Space Warfare XII. Plus, don't you hate Honorverse?
My point was that in that setting shipping of stuff (which includes ships) had become cheap enough to allow symmetrical warfare between ships. We can't assume that.
Byron:
"Point, but it doesn't really change the central thrust of my argument. Both sides were trying to conquer territory at some point. Symmetrical war aims will mean symmetrical war means."
One has to be careful about how one defines symmetry, however. The continental powers really never developed long range bombers, whereas the oceanic powers did. The same can be said of navies. Yes, the German navy punched way above it's weight for a continental navy, but it have a reason to; the Soviet navy's coastal focus during the war was more in line with a continental power's priorities.
In space, if all one wants to do is dominate the orbitals of one's own planet, one can be quite a successful conqueror without resorting to the means an interplanetary conqueror might have to. Symmetry of mean only reall applies given an actual symmetry of situation, not just parallel goals at the conceptual level.
"OK, but now raise the fraction of power required for projection tenfold. Suddenly, you need an even bigger overmatch.
I'm going to guess that to be able to do something like a blockade, you need an order of magnitude more economic power than your enemy. To be able to control their orbits (destroy their space forces and some ground-based defenses, while not worrying too much about low orbit) would take two. An invasion would probably take three or more."
I think you're being a bit liberal with orders of magnitude. But whatever the actual ratios are, the nature of warfare will be decided by what can be effectively done. If it's too exepnsive to conquer the enemy's planet, you'll hold his cities hostage to nuclear (or RKV) attack, and demand capitulation. When he gives up, move in your MPs. If he doesn't give up start the bombing until he does. The decisive act in any interplanetary or interstellar war will likely be defeating the enemy navy and accounting for any retaliation squadrons that might be floating about. (Because you don't go around threatening the other guy's cities when he can counterattack yours.) Once you assure space dominance, all the enemy can do is have his planetary defenses bombed out of existence then go guerilla.
"Plus, I'm pretty sure that most of those extra divisions wouldn't have been ready in time to fight anyway."
Sure they would have, if the resources that went into oceanic logistics and hundreds of thousands of aircraft had gone into them instead. The Germans had a couple of hundred divisions on a smaller resource base, raised over a period of about five years. But they didn't have to move them overseas.
"Yes. This reminds me of something. Say, my arguments in Space Warfare XII. Plus, don't you hate Honorverse?"
In SW XII I was arguing the technical means of getting down on the surface, and subsequently expanding a beachhead. I would agree that it would take some pretty special economic and strategic circumstances for it to be practical.
WRT Honorverse, I can find a setting's overal context non-credible, yet still reason within it constraints. I don't suffer from cognitive dissonance.
"My point was that in that setting shipping of stuff (which includes ships) had become cheap enough to allow symmetrical warfare between ships. We can't assume that."
And my point was that it couldn't even be assumed in that setting. Even today, when a round trip to Europe is within most middle class persons' credit limit, governments would have a tough time mounting overseas invasions against peer or near-peer comptetiors. And the Honorverse's economics are closer to those of the early to mid 19th Century.
Byron:
"Though I'm thinking that "border skirmish" will be a misnomer in space."
Yeah. (FTL-less space, anyway.) A better example would be, say, Mars and Luna squabbling over stakes in the asteroid belt.
"I'm going to guess that to be able to do something like a blockade, you need an order of magnitude more economic power than your enemy. To be able to control their orbits (destroy their space forces and some ground-based defenses, while not worrying too much about low orbit) would take two. An invasion would probably take three or more."
Can you even have spacegoing powers with three orders of magnitude between them in the plasible midfuture?
I'd expect that by the time a colony has developed to the point of being able to launch its own spaceships it would already be less than three orders of magnitude smaller than Earth.
Tony:
"One has to be careful about how one defines symmetry, however. The continental powers really never developed long range bombers, whereas the oceanic powers did. The same can be said of navies. Yes, the German navy punched way above it's weight for a continental navy, but it have a reason to; the Soviet navy's coastal focus during the war was more in line with a continental power's priorities."
In the ocean of space, there is no such thing as a continental power.
"If it's too exepnsive to conquer the enemy's planet, you'll hold his cities hostage to nuclear (or RKV) attack, and demand capitulation."
It may be useful to implement the Mongol method - simply demand that they send you regular shipments of tribute or be destroyed, without otherwise attempting to personally control their government.
Tony:
In space, if all one wants to do is dominate the orbitals of one's own planet, one can be quite a successful conqueror without resorting to the means an interplanetary conqueror might have to. Symmetry of mean only reall applies given an actual symmetry of situation, not just parallel goals at the conceptual level.
Yes, but as Milo said, there aren't continental powers. And my entire point is that symmetry of situation is not going to happen, even to the level that it did during WWII, which I will admit wasn't perfect, but it was far better than we've seen since.
Sure they would have, if the resources that went into oceanic logistics and hundreds of thousands of aircraft had gone into them instead. The Germans had a couple of hundred divisions on a smaller resource base, raised over a period of about five years. But they didn't have to move them overseas.
OK, I messed up on that one.
I'll leave aside Honorverse economics for now.
Milo:
Can you even have spacegoing powers with three orders of magnitude between them in the plasible midfuture?
I'm not sure you can either. If we're liberal with our definition of spacegoing, maybe. Of course, if the powers in question are closer together, it becomes easier. Europa might get away with invading Ganymeade, which is only 10% of it's size.
Thinking about what Byron, Milo, Tony and a few others have said, I think that I can come up with an example:
The U.S. decides to invade the nation of the Grand Republic of Northern Barsoom, a cluster of about a dozen domed/underground city-states whose government threaten the rest of the Mars colonies. Obviously this takes place centuries from now, but we'll put a few constrants on it. Flight time between Earth and Mars during the "off-season" is about three months, and "on-season" is six weeks. The population of the U.S. at this time is about the same as it is now; 300 million. 1% of its population is under arms, with half of this number being support troops. The U.S. can only send a maximum of 1% of its combat streigth to Mars; probably closer to 1/2%; that would be 3000 combat troops. The population of the GRNB is 240,000 so 1% is 2400; one 1200 man support regiment and a 1200 man mechanized infantry regiment. So the U.S. can send 3000 light infantry that has to use local civilian transport( or whatever military transport that can be manufactured on-site); Because it would be politically disasterious for the Americans to bomb the GRNB due to the massive civilian casualties that would result in. So, six battalions of light infantry vs. a mechanized infantry regiment? Even though the U.S. can rotate out troops and thus maintain a troop streigth of six battalions year after year, it might take six months before a wounded soldier could be shiped home. A typical two year deployment could be six months to and fro plus a year-and a half on the ground; Personally, I think that it will either be a long, drawn out affair, or a very quick defeat for one side or the other. What do you guys think?
Ferrell
Byron:
"Yes, but as Milo said, there aren't continental powers. And my entire point is that symmetry of situation is not going to happen, even to the level that it did during WWII, which I will admit wasn't perfect, but it was far better than we've seen since."
But you said, earlier today (emphasis added):
"Point, but it doesn't really change the central thrust of my argument. Both sides were trying to conquer territory at some point. Symmetrical war aims will mean symmetrical war means."
My observation in response to that was that you have to be careful how you classify "symmetrical war aims". Going back to our WWII example, I think it's safe to say that both the Western Allies and the Soviet Union had the same war aims WRT Nazi Germany. But they did not have a symmetrical strategic situation. Soviet Russia shared a continent with Germany, and could in apply roughly symmetrical means, including air forces optimized for interdiction and ground support, and a mix of mechanized and horse drawn tactical divisions. The Western Allies, on the other hand, had to bring resources ffrom overseas, then enter Western Europe amphibiously. So the Western Allies chose to emphasize strategic air power and motorization to the maximum extent (petroleum products are less bulky and easier to move than fodder, plus they don't spoil).
So, symmetric aims don't always mean symmetric means.
Re: Ferrell and his uppity Barsoomians
Presumably the US would have a space navy capable of interdicting large troop movements on the surface of Mars or using suborbital rockets. So US forces could isolate and concentrate on one population center at a time.
Great discussion! Strategy is something I've not yet discussed in the Space Warfare series, and for a reason - you have to have some sense of the technological possibilities and constraints in order to frame a strategic discussion.
I agree that planetary invasion is an awesomely expensive process, even in operatic settings.
Let me think a bit about blockade. A 'close' blockade (low orbit) is inherently asymmetrical in that you're pitting spacecraft against surface-based defenses.
A 'distant' blockade is less asymmetrical in that it presumably involves only space based weapons on both sides. (Any surface launched ASAT needs at least an ICBM equivalent booster, and still travels thousands of km through space to reach its target.)
The disparity between attacker and defender in this case seems no more than an order of magnitude, perhaps less. Both sides have weapon installations in the form of lasers, kinetics and their launchers, whatever.
The defender can deploy these aboard orbital platforms, which probably have OMS level propulsion. Human personnel can be based aboard the platforms, aboard an orbital support station, or possibly ferried up from the surface. (Probably not during combat, but onboard crews may not be needed during combat.)
The attacker needs equivalent weapon platforms, and (we'll assume) either onboard crews or support hab(s). All this stuff essentially costs the same on both sides. But the attacker also needs deep space drive buses to carry their stuff to the objective, and then eventually bring them back or else support them on station.
Using my simple rule of thumb for spacecraft costs, the drive bus costs on the same order as its payload. With logistic support the disparity could approach the classical 3:1 resource ratio between attacker and defender. But in a setting where large scale deep space travel (interplanetary or interstellar) is available at all, probably no more than 10:1.
But bear in mind that this is only for 'distant' blockade. Full control of a planet's orbital space costs a lot more, and invasion beaucoup more.
The most nearly symmetrical scenario, it seems to me, would be two space powers tussling over some back-of-beyond planet.
Rick:
"But bear in mind that this is only for 'distant' blockade. Full control of a planet's orbital space costs a lot more,"
I don't think that's necessarily true. The major expense in any blockade is the logistics cost of establishing and keeping the blockade on station. Establishing a close blockade of a planet by presumably eliminating the orbital defenses involves only the additional marginal cost of ammunition expended and incurred combat losses to do so.
"and invasion beaucoup more.
The most nearly symmetrical scenario, it seems to me, would be two space powers tussling over some back-of-beyond planet."
Here we get into issues of concentration of Mass, Maneuver, Economy of Force, Surprise, and Security. If the attacker can concentrate enough force to take the objective before the defender can reinforce and/or counterattack, an effective local superiority might be generated to take a planet. Of course, powers that are relatively equal economically might go back anf forth like this for centuries, or one of them (acting much like the English did against the Welsh over the course of several generations) might establish strategic superiority one castle (i.e. solar system) at a time.
Also, rereading some of my comments on the infamous Space Warfare XII, I recall that one of the things I said then was that if the defenders are sufficiently averse to being governed by the attackers (feeling they might be enslaved, or their religion destroyed, or whatever) they might make it a matter of having to actually conquer the planet on the ground.
Byron's Taxonomy of Space Warfare, Part II:
III: Interbody Warfare
This is warfare between two or more powers on different celestial bodies. This includes situations where one power is on an orbital around a seperate body.
This section will be structured differently then the others, as there are a lot more factors involved here. It's more of a list of various enviroments that I could think of.
A. Intrasystem
The powers are based on celestial bodies within the same planetary system, either with one on the planet and another on the moon, or with both on separate moons. Delta-V for spacecraft will likely be low, and transit times will be on the order of days. Fighters are on the edges of possibility, though slightly larger craft (I'll designate them as LACs) are more likely.
B. Intersystem
The powers are in different planetary systems. Transit times will be on the order of months, and delta-V requirements will be high. There are several specific enviroments within this.
1. Interplanetary transfer
This applies to any ships in an interplanetary transfer orbit. High delta-Vs are required, as is long endurance. Closing velocities during battles will be high, and I don't expect to see "fleet battles" during this stage. The attacking fleet will be opposed mostly by KKVs.
2. Outer orbits
The outer orbits are orbits that are at the edge of the Hill sphere of a body. They are likely to be mostly empty except for the lagrange points, and can be seen as relatively flat. An attacking fleet will likely move into the outer orbits first, and probably be opposed by the defender's fleet there. For the attackers, ships will likely be their interplanetary vessels. The defender might have specialized vessels for this as well, which lower delta-V then interplanetary vessels. Encounter speeds will be low. The reason for engaging this far out is to minimize debris problems and colatteral damage.
3. Middle orbits
Middle orbits are the orbits where a significant orbital curvature appears, and strategically significant objects begin to be seen, but where spacecraft are out of range of most ground-based defenses. Ships built to fight here will probably be low delta-V (nuke-thermal class). The defender will be at a disadvantage, as the attacker can shoot into these orbits with his outer orbit warships.
4. Low orbits.
These orbits are going to be the most cluttered, as well as being in range of ground-based defenses. Fighters and LACs will most likely be the primary warcraft here, supported by either ground defenses or by interplanetary ships. Delta-Vs will be low, with high accelerations.
Tony:
I'm fairly sure that nobody will disagree that on a broad level, World War II was symmetrical. I'm speaking of that sort of symmetry. Both sides were trying to size territory, or hold it under their control. Those are fundamentally symmetrical goals, and so symmetical means (infantry, tanks) were used. We won't see that sort of thing in space.
The major expense in any blockade is the logistics cost of establishing and keeping the blockade on station. Establishing a close blockade of a planet by presumably eliminating the orbital defenses involves only the additional marginal cost of ammunition expended and incurred combat losses to do so.
That's true, but you assume that the number of ships required for each type is the same. That's not even close to the truth. A far blockading fleet requires a force capable of destroying the defender's mobile forces and defeating any possible relief fleet. A close blockade will require all of that, plus the ability to defeat fixed defenses. I'm going to bet that the fixed defenses are going to be a lot tougher.
Of course, powers that are relatively equal economically might go back anf forth like this for centuries, or one of them (acting much like the English did against the Welsh over the course of several generations) might establish strategic superiority one castle (i.e. solar system) at a time.
Where did that come from? I purposely exculded interstellar warfare from my taxonomy, as it's far too dependent on the variables involved. Even then, the force deployment cost will likely be too great, unless we're dealing with large empires.
Rick:
Did you get my email about the spreadsheet?
The most nearly symmetrical scenario, it seems to me, would be two space powers tussling over some back-of-beyond planet.
That's pretty much what I think, too. Though if we have, say, multiple gas-giant moons fighting, the transit cost goes down significantly.
And I agree with you on strategy. It's too hard to do unless you have a firm tech level.
While thinking about my taxonomy (sorry for the delay, BTW) I've come to the conclusion that space warforces will develop along multiple paralell lines. Here's an example:
In the year 2283 there are two superpowers on Earth (the US and China) and a space colonies on Mars, Callisto and Ganymeade. The US and China have OPVs (Orbital Patrol Vehicles) to inspect the traffic in Earth orbit. The OPVs are small craft, with a crew of half a dozen and a dozen-man boarding party, along with a few small lasers. They're chemfuel, and operate from orbital bases.
Callisto and Ganymeade get into a feud over voliatle mining on Europa. Both have mines there, and Callisto says that Ganymeade is taking more then they are allowed to. Eventually, they mount weapons on a transport, and stop a Ganymeadean ship for inspection. The response is small, chemfuel craft carried as riders on transports. They're manned, as automation is hard to set up quickly. Space fighters. (Yes. I know it's heresy. However, it makes sense as a jury-rigged solution.)
Callisto responds with the same. Soon the situation escalates, with both sides converting a few transports full-time. Fighters remain the primary warcraft because neither side can afford that many full-time tranport conversions.
The US and China get annoyed at this, and decide to do something about it. The Jovian McGuffinite is too valuble to allow the supply to be threatened. Not having anything better, they cobble together a carrier and attach a bunch of OPVs to it. When it gets to Jupiter, there are two problems.
1. Neither side wants the crisis solved by Earth, at least the way Earth wants it solved. The carrier has no local supplies, sharply limiting it's use.
2. The Jovian fighters are more powerful than the OPVs.
Eventually the crisis is solved somehow. Ganymeade and Callisto remain at odds. Each body set (Earth, Mars, Ganymeade and Callisto) develops it's own set of space forces. Earth keeps the OPVs for orbital patrol. It also develops a deep-space fleet. Classical laser/kinetistars, etc. Ganymeade and Callisto develop nuke-thermal and chemfuel craft better suited for warfare around Jupiter. They're more worried about each other than Earth. Mars looks at what had happened and decides that they don't want Earth meddling in their affairs. They build a fleet that's similar to Earth's but lacks much deep-space capability. It's more kinetic-heavy as well.
Each has a seperate, paralell fleet because they had different starting points, but all of them work.
Byron:
"I'm fairly sure that nobody will disagree that on a broad level, World War II was symmetrical. I'm speaking of that sort of symmetry. Both sides were trying to size territory, or hold it under their control. Those are fundamentally symmetrical goals, and so symmetical means (infantry, tanks) were used."
But, as I previously pointed out, even with broadly consisten war aims, whether you were a continental or an oceanic power significantly effected your choice of means. Yes, at points of contact on the ground the tactical forces all used infantry AFVs, and various types of artillery. But at the operational level, the oceanic powers were much more dependent on motorization, independent of animal transportation, and made significant use of sea transport. The continental powers still had most of their logistics (and large portions of their artillery parks) horse-drawn, and used waterborne transportation only very marginally -- mostly on the Black and Baltic Seas. At the strategic level, the oceanic powers required sea commerce to wage the war at all, and also conducted significant, long-duration strategic air campaigns. The continental powers were all about riding rails to the front, and only dabbled ocassionally (and by late war standards very amateurishly) in strategic bombing.
You may wish to handwave all of that away to concentrate on tanks and guns. But the differences of logistic means, particularly the strategic sanctuary that the United States and Canada occupied in North America, and the additional resource bases they could access in Africa and South America, were decisive. Even when you consider the two truly symmetric continental powers, Nazi Germany and Soviet Russia, the physical strategic depth of the Soviet Union was decisive early in the war. The Germans reached the Volga River at Stalingrad, and still had all of Soviet Central Asia and Siberia before them. Two years later, the Soviets, Bellying up to the Vistula River in Poland, were no further from the industrial heart of Germany than Leningrad was from Moscow.
"We won't see that sort of thing in space."
Why not? The US and China, for example, fighting over interests in Martian Space could easily deploy roughly symmetrical forces to the battlespace. And each in turn might find itself the attacker or deffender, as reinforcement squadrons approach Mars. In a wider war, these adversaries might engage in a roughly symmetrical contest in Earth orbit, to determine who would control access to space, which would in turn determine who won at the far end around and on Mars.
"That's true, but you assume that the number of ships required for each type is the same. That's not even close to the truth. A far blockading fleet requires a force capable of destroying the defender's mobile forces and defeating any possible relief fleet. A close blockade will require all of that, plus the ability to defeat fixed defenses. I'm going to bet that the fixed defenses are going to be a lot tougher."
What do you consider "fixed defenses"? Orbital forces are just space forces without much (if any) propulsion. Fighting them does involve extra cost, as I've already identified. But once you have suppressed the orbital forces, the circumvallation portion of the blockade is all about keeping the planet from launching into space, which the blockader should have an easier time with than catching blockade runners already in space. The contravallation force's job of preventing relief/reinforcement is essentially the same. How could all of that be so much more expensive?
"Where did that come from? I purposely exculded interstellar warfare from my taxonomy, as it's far too dependent on the variables involved. Even then, the force deployment cost will likely be too great, unless we're dealing with large empires."
Byron:
"Where did that come from? I purposely exculded interstellar warfare from my taxonomy, as it's far too dependent on the variables involved. Even then, the force deployment cost will likely be too great, unless we're dealing with large empires."
I was responding to Rick:
"The most nearly symmetrical scenario, it seems to me, would be two space powers tussling over some back-of-beyond planet."
It's not always about you, B.
Rick:
"Strategy is something I've not yet discussed in the Space Warfare series"
The thing with strategy in space warfare is that unless you have FTL, well, most of it will be unique.
Lessons learned from jungle warfare in Vietnam could, hypothetically, be put to pretty good use if the same army later found itself fighting in the jungles of Congo.
But in the solar system, there are only a very limited number of places we're likely to care about at all, and each has its own character. The only "mass-produced" environment would be asteroids, which might be fought over if asteroid mining is profitable, but I don't think they'll be all that important.
"Let me think a bit about blockade. A 'close' blockade (low orbit) is inherently asymmetrical in that you're pitting spacecraft against surface-based defenses."
I generally perceive the word "blockade" to refer only to what you call a "distant" blockade. Once you enter low orbit, you've moved past blockade and into all-out attack.
Even if you never actually land troops, then a battleship on the shore shelling coastal targets is hardly a blockade, is it?
And flying within range of surface-to-orbit defenses without shooting back at them is the same as pinning a post-it saying "kill me" on your back.
Tony:
OK, you have me on WWII. It's about as symmetric as any war can be expected to be, and even then it wasn't terribly so.
Why not? The US and China, for example, fighting over interests in Martian Space could easily deploy roughly symmetrical forces to the battlespace. And each in turn might find itself the attacker or deffender, as reinforcement squadrons approach Mars. In a wider war, these adversaries might engage in a roughly symmetrical contest in Earth orbit, to determine who would control access to space, which would in turn determine who won at the far end around and on Mars.
I probably should have phrased that better. We won't see symmetrical invasions in space. The only case where some sort of symmetry will occur is when both sides are deploying.
What do you consider "fixed defenses"?
Let me digress for a moment and explain how I would conduct a blockade under PMF assumptions.
After you defeat the defenders, set up a base in outer orbit. You can see any incomings months out, and anyone trying to take off will take a long time to pile on sufficient delta-V, allowing intercept. When someone starts coming, move to intercept in outer orbit. Even better, send a missile, and make them come to you.
I'll define fixed defenses simply:
It's the stuff I don't have to deal with if I choose to establish a far blockade. Stuff on the planet or stations in low orbit would be unable to engage me unless I go to them.
"The most nearly symmetrical scenario, it seems to me, would be two space powers tussling over some back-of-beyond planet."
I would have interpereted that as a case of both deploying, and it doesn't really require interstellar travel. Your case of Mars is the same.
Milo:
I generally perceive the word "blockade" to refer only to what you call a "distant" blockade. Once you enter low orbit, you've moved past blockade and into all-out attack.
That's a very good point. Also, there is no reason to blockade from low orbit. You can see LEO from far out, and move to intercept.
Milo:
"I generally perceive the word "blockade" to refer only to what you call a "distant" blockade. Once you enter low orbit, you've moved past blockade and into all-out attack.
Even if you never actually land troops, then a battleship on the shore shelling coastal targets is hardly a blockade, is it?
And flying within range of surface-to-orbit defenses without shooting back at them is the same as pinning a post-it saying "kill me" on your back."
In space a distant blockade would be allowing enemy ships to launch into planetary orbit unmolested, but engaging them if they tried to make an interplanetary or interstellar transit. A close blockade would be the elimination of defending orbital forces and shooting at anything that triesto launch into orbit. Depending on your technical assumptions, either or both could be possible, and either or both could make strategic sense, depending on the circumstances.
Tony:
In space a distant blockade would be allowing enemy ships to launch into planetary orbit unmolested, but engaging them if they tried to make an interplanetary or interstellar transit. A close blockade would be the elimination of defending orbital forces and shooting at anything that triesto launch into orbit. Depending on your technical assumptions, either or both could be possible, and either or both could make strategic sense, depending on the circumstances.
I'm not sure when the close blockade would make sense as a blockade. As Milo said, that would be an attack.
A blockade is an interdiction of transit. It is not the destruction of stuff that is already there. Stuff exists in low orbit, it doesn't transit it. I suppose you could call it a blockade if there was nothing in low orbit to start with. However, if you have to clear it first, then it's not a blockade.
Tony:
Definitons of types of blockades, from wikipedia:
A close blockade entails placing warships within sight of the blockaded coast or port, to ensure the immediate interception of any ship entering or leaving.
In a distant blockade, the blockaders stay well away from the blockaded coast, and try to intercept any ships going in or out.
In any sort of realistic space enviroment, all blockades will be, in effect, close. You can see anyone trying to get in or out. You tell them to stop. If they don't, shoot at them. Simple.
Your "close blockade" is more akin to shooting up all of a nation's ships, and then shooting at any they try to launch, and calling it a blockade. I would not classify it as such.
I did think of another kind of blockade, the Kessler Blockade. If you can cause a debris catastrophy in low orbit, it should serve to blockade the planet in question for a while without much effort on your part. Even if they have laser brooms, it should still take months to clean the orbit.
Byron:
"I probably should have phrased that better. We won't see symmetrical invasions in space. The only case where some sort of symmetry will occur is when both sides are deploying."
That's always true at the operational level, which is what we're talking about here. Even with perfectly symmetrical tactics, training, and equipment (e.g. American Civil War) two sides will most likely be in different tactical postures. One might be deffending and the other attacking, or one might be withdrawing while the other is advancing, etc.
"I would have interpereted that as a case of both deploying, and it doesn't really require interstellar travel. Your case of Mars is the same."
Any planet worth fighting over in our solar system in the PMF is not going to be "back-of-beyond". It's going to be valuable enough to both parties to make fighting a more justifiable option than anything else. Fighting over inconsequential planets implies a lot of planets, not just eight, and an ease of transport that an inconsequential one can be squabbled over with surplus resources.
Byron:
"They're manned, as automation is hard to set up quickly. Space fighters. (Yes. I know it's heresy. However, it makes sense as a jury-rigged solution.)"
I can accept that, actually. I'm confident that we can automate a lot of things if we have time to design and test it, but nothing beats live humans for reliable jury-rigging.
The question is how likely a power is to immediately launch into combat with jury-rigged weapons rather than taking a little longer to get it right. Did no-one see the war coming?
"Ganymede and Callisto develop nuke-thermal and chemfuel craft better suited for warfare around Jupiter. They're more worried about each other than Earth."
These craft are still quite effective defensively against Earthly aggression, they just can't be used in a counterattack.
"OK, you have me on WWII. It's about as symmetric as any war can be expected to be, and even then it wasn't terribly so."
Let's take this from the other direction. We're not specifically after "symmetric" or "asymmetric" war, we're after war that appeals to us on a certain aesthetic level, which just happens to include a certain degree of symmetry.
Since everyone keeps talking about WWII in SPACE! as an operatic ideal, it seems that WWII is, by whatever measure, sufficiently symmetric. Meanwhile, people don't seem to like the war in Afghanistan, so that war must be insufficiently symmetric.
The only situation where a highly symmetric war is explicitly stipulated as a design goal is in strategy games, where it's desirable to create a "fair" game balance for both players. But strategy games are always kinda unrealistic in that they overlook the whole "the only winning move is not to play" aspect...
Tony:
I'm not going to argue the intent of that statement with you. Plus, I only count 4 planets, not 8. And who wants Venus? :)
Milo:
The question is how likely a power is to immediately launch into combat with jury-rigged weapons rather than taking a little longer to get it right. Did no-one see the war coming?
Pretty much. It just sort of happened. This is just a possible scenario.
The only situation where a highly symmetric war is explicitly stipulated as a design goal is in strategy games, where it's desirable to create a "fair" game balance for both players. But strategy games are always kinda unrealistic in that they overlook the whole "the only winning move is not to play" aspect...
But that's no fun at all. I do have to agree with you in general, though.
Byron:
"I did think of another kind of blockade, the Kessler Blockade."
Does that actually work?
It's not enough to dump debris into one orbit. If you Kessler the ecliptic, say, they I can launch inclined orbits that don't cross the ecliptic until they clear above the altitude of the debris disk. So you need a spherical shell of debris.
Furthermore, I could probably push through a debris ship using armored spacecraft. The armor cuts down my ships' efficiency, but I'm not completely groundbound - and if we can afford extensiuve human presence in space, then I think I can afford some armored bulldozers.
Tony:
"Any planet worth fighting over in our solar system in the PMF is not going to be "back-of-beyond". It's going to be valuable enough to both parties to make fighting a more justifiable option than anything else. Fighting over inconsequential planets implies a lot of planets, not just eight, and an ease of transport that an inconsequential one can be squabbled over with surplus resources."
The crucial factor here is not how "inconsequential" it is, but rather than the planet under contention is not the homeland of either of the two superpowers fighting over it.
Replace planet with asteroid, and you can even get something reasonably inconsequential in our solar system.
Byron:
"I'm not sure when the close blockade would make sense as a blockade. As Milo said, that would be an attack.
A blockade is an interdiction of transit. It is not the destruction of stuff that is already there. Stuff exists in low orbit, it doesn't transit it. I suppose you could call it a blockade if there was nothing in low orbit to start with. However, if you have to clear it first, then it's not a blockade.
Definitons of types of blockades, from wikipedia..."
You're thinking way too literally here. Conceptually, a close blockade is designed to keep enemy trade form leaving port, because once he leaves port, he has all of the ocean to get lost in. If you have control of choke points, you can establish a distant blockade at the choke points, because it's easier than going in and defeating the enemy coastal forces and establishing a close blockade.
Looking at historical examples, the Union in the American Civil War established a close blockade of Confederate ports, because trying to hunt down blockade runners at sea was simply fruitless. Conversely, the British Royal Navy in WWI controlled the exits to the North Sea, so it made no sense to go in and fight the minefields and torpedo boats of the Germans. German maritime trade and naval forces could easily enough be bottled up by a distant blockade controlling the northern and western exits.
Translating this to space, keeping the enemy from getting off the ground into space is probably going to work much better than letting him into orbit, from where he can choose his time and means of departure. Likewsie, maintaining close control over traffic from the surface puts you into position to control traffic trying to get down to the surface. Yes, in space you can see everything, but the larger volume you attempt to control the more force you need. With a distant blocakde while you're intercepting one blockade runner, or two or three, it's much easier for others to slip through, if the runners' timing is good. If you are closer in to the plaent? Not so much. So you can define a close blockade as a blockade where the defending orbitals have been cleaned out and the blockade force establishes effective patrols as close as possible without having to regularly fight it out with ground-based defenses.
A distant blockade really only recommends itself where the defending orbitals are just too expensive to clean out, or where choke points exist, such as jump points, or approaches to the objects of enemy trade. Yeah, that's right, it might be easier to control trade flowing into neutral trade planets than it would be to actually blockade the enemy planets.
Milo:
My plan (and this is a top-of-the-head thing) is to use the stuff that's already there. You just start shooting, and what you hit produces more debris, and so on. It's not perfect, but it should put a big dent in the space capacity. All spacecraft have to be armored until they reach upper orbits. That's going to cost a lot. It might have to be backed up with ships, but it might be an effective means of short-term orbit denial.
Tony:
You're thinking way too literally here. Conceptually, a close blockade is designed to keep enemy trade form leaving port, because once he leaves port, he has all of the ocean to get lost in. If you have control of choke points, you can establish a distant blockade at the choke points, because it's easier than going in and defeating the enemy coastal forces and establishing a close blockade.
I already addressed this. I will admit, theoretically, that it is better not to let him into orbit at all. As a practical matter, you have the fact that 1. your close blockade is really an attack, and 2. because of that, you have to deal with all of his defenses, not just his fleet. In space, you can't get lost. I've already addressed the rest of this. Plus, won't interplanetary transfer orbits (whatever is dictated by setting) form the choke points in question?
I really don't get this. I can see everyone in the area, and people are going to have a really hard time slipping by. It takes a ship a 1 miligee 28 hours to put on 1 km/s. We're looking at days for departure. I just have to put some kinetics in his path during that time. Anyone coming in has to stop by for inspection (if I'm letting anyone through) or they get the same treatment. It's a lot safer and cheaper for me. Look at it this way. My blockade is 95% effective. Yours is 99% effective, and costs 10 times as much. Whose is better?
On a meta level, you're thinking navally. This is usually OK, but it's a real problem right now. Unless we're going to do "but they have to have torches for this to be happening" again. I'd rather not.
I think I like Tony's classification of close vs distant blockades in space. As long as a close blockade stays out of range of easily-hidden surface-to-orbit weapons (THAAD-class, as per SWXII), it isn't required to engage the surface at all. It retains more options to do so, however, which may be worth the extra costs to attain it.
Byron:
"It takes a ship a 1 miligee 28 hours to put on 1 km/s. We're looking at days for departure."
Not necessarily - you're assuming nuke electric or similar. Nuke thermal (or chemfuel, for sufficiently small payloads) could still threaten to evade a distant blockade, given burn times of minutes or hours (and carefully chosen vectors). Or, for that matter, mount a counterattack.
"Plus, won't interplanetary transfer orbits (whatever is dictated by setting) form the choke points in question?"
Each launch window for each destination will have its own particular orbit. At the very edge of the planet's Hill sphere, these orbits will be close in delta-v terms, but given the radii of such orbits that also implies a much, much bigger volume of space to control.
"And who wants Venus? :)"
Me, actually. Human-breathable atmosphere is a good lifting gas. There's plenty of CO2 to extract material for all the Super Nano Carbon Stuff you'd need. Thermal and wind gradients galore for power. And if you're looking for a setting with something resembling much of how space warfare is depicted in Hollywood, the upper atmosphere of Venus is actually pretty close to what you'd want: ships, stations, stealth, and no battles at Stupendous Range.
Byron:
"I already addressed this...Unless we're going to do "but they have to have torches for this to be happening" again. I'd rather not."
With all due respect, I don't buy into the closed-assumptions game. If you don't want to talk about the things I'm talking about, you don't have to respond.
But even if we go with your assumptions, for any given level of technology, the larger volume of space you try to interdict the harder you make things on yourself. While your cruisers A, B, and C are inspecting merchants X, Y, and Z. Blockade runners can be getting through. That holds even with the limited trajectory assumption, because a blockade enforcer can only physically match orbits with one other vessel at a time. If the blockade runners send in more vessels than can be handled, they will get some through.
This in fact would be one of the motivations for shooting first and asking questions later. It may only be possible to deter blockade running by making it too expensive in terms of resources and lives. Even at that, nobody's space weapons are going to be magic. While the available patrols close in on a given attempt at the blockade, other runners are out of range and getting through. If it takes sacrificing cargo for reaction mass to do this, guess what? It's a cost of doing business, not a show stopper.
Finally, your characterization of suppressing orbital defenses as an attack is technically correct, but so what? The Nelsonian RN had to run the French and Spanish navies off the high seas before they could blockade French and allied ports. And once the orbital forces are suppressed, there's nothing forcing the attacker into fighting it out with ground-based defenses. He can settle into a close blockade, just ouside the range of ground-based weapons. Yes, it's more expensive than a distant blockade, but also probably enough more effective in certain circumstances to be justified.
Tony:
With all due respect, I don't buy into the closed-assumptions game. If you don't want to talk about the things I'm talking about, you don't have to respond.
I understand that, but at the same time, I really don't want to repeat that arguement.
But even if we go with your assumptions, for any given level of technology, the larger volume of space you try to interdict the harder you make things on yourself. While your cruisers A, B, and C are inspecting merchants X, Y, and Z. Blockade runners can be getting through. That holds even with the limited trajectory assumption, because a blockade enforcer can only physically match orbits with one other vessel at a time. If the blockade runners send in more vessels than can be handled, they will get some through.
One of the interesting things I've noticed is that it's far easier to run a blockade from the inside than the outside. As Raymond noted, an NTR might allow you to evade blockaing vessels.
However, this comes down to the purpose of blockades. Is it really there to completely stop all commerce? The Union blockade certainly didn't. I think somewhere over 75% of blockade runners got through. So was it a failure? Not at all. Blockade runners aren't good cargo vessels. And normal cargo vessels couldn't get through the blockade. In the scenario we're assuming, nuke-electric is the norm. NTRs will be far less efficient. So how much does the blockade cost in terms of payload cost? Does it double it? Quadruple it? More?
As to inspection, that's quite simple. Make them come to you. When a ship approaches, hail it. Tell it that you are sending out a blockade missile. The blockade missile will rendezvous with it and attach to the hull. It will detonate if they deviate from it's course or they open the airlocks. It is then ordered to rendezvous with the blockading force. When it arrives, the missile is detatched after the inspection team clears the ship. Failure to comply results in the ship being shot at with normal missiles.
Tony:
Your plan (going in low and denying orbit) strikes me as something like this, in civil war terms:
Instead of putting ships inside the blockade, why don't we send our ships into the harbor, and destroy their navy their? Then we take out their defenses, and sit there until they try to launch more ships. When they do, blow them up.
A blockade is never expected to be airtight. It increases the cost of moving cargo significantly. If the cost is high enough, it's achieved it's objective.
Raymond:
I am aware of how the orbits work. Again, it's more of a denial of the best options than making it completely airtight.
Raymond:
"Nuke thermal (or chemfuel, for sufficiently small payloads) could still threaten to evade a distant blockade,"
It would get a head start, but it would be travelling much more slowly afterwards. Just chase it down.
"There's plenty of CO2 to extract material for all the Super Nano Carbon Stuff you'd need."
And no rock to extract the material for everything else you need.
"Thermal and wind gradients galore for power."
And no fission or fusion fuels in sight for when you really need power. Like for space travel.
Milo:
We're not sure at present what sort of minerals are available on the surface of Venus in useful quantities. I would submit, however, that the same carbon nanostuff expected to stand up to battle lasers would work well as a shielding material for surface exploration (with suitable cooling for the interior, of course).
Water would be something of a problem to acquire - but if you're constructing a setting, that's a feature, not a bug. Gives Venusians a good reason to maintain space access.
Tony said:"Re: Ferrell and his uppity Barsoomians
Presumably the US would have a space navy capable of interdicting large troop movements on the surface of Mars or using suborbital rockets. So US forces could isolate and concentrate on one population center at a time."
So the U.S. forces should substatute one infantry battalion with a Mars-optimized Predator squadron? That makes sense.
Ferrell
Byron -
Yes, I did get the email - I just haven't caught up with it yet. (Sorry!)
Well, I introduced the terms 'distant' and 'close' without defining what I meant by them. Primarily I was thinking about exposing your ships to ground fire, and secondarily of any civil orbital clutter that might complicate your rules of engagement.
By 'blockade' I mean interdicting deep space travel between a planet and distant locations, not orbital travel. Yes, there are complications! Earth-Moon travel is 'semi-deep space' in this context, compared to Mars-Phobos travel.
My feeling is that with quasi-realistic drives, distant blockade is as effective for interdiction as close blockade. As noted, high ISP drives have such low acceleration that you have plenty of time to plot an intercept, while relatively high thrust drives, like nuke thermal, have such limited ISP that their fast getaway amounts to peeling away from the curb in front of the bank, then continuing on in low gear.
(If you're using an Orion blockade runner, I'll nail that sucker and say it was a warship. Who's really gonna complain?)
Come to think of it, blockade rules of engagement are an interesting question. 'Zap without warning' is not an issue, because I can certainly warn any incoming or outgoing ship, and order it to enter an inspection orbit. But if a ship doesn't comply?
My gut feeling is that I might not want to destroy civil passenger types, because I have read my post-medieval Terran history, and know how well the Lusitania ultimately worked out for imperial Germany. So those ships I probably want to intercept and board. If they resist by force, I am in my rights to shoot.
If the ship is obviously not a civil passenger type (for example, it has quick-getaway acceleration), then screw sending a gunship with boarding party - I'll missile or zap it.
My sense of it is that space law would probably go roughly along those lines.
Oh, also, in my remark on empires contesting a back-of-beyond planet, I was indeed thinking of interstellar scenarios, because in many cases they are effectively the same, so far as discussions like this one are concerned. Any FTL where you travel a few AU in normal space, do a handwave, then travel a few more AU to reach the destination, is in most respects just interplanetary travel with a handwave.
Rick:
Come to think of it, blockade rules of engagement are an interesting question. 'Zap without warning' is not an issue, because I can certainly warn any incoming or outgoing ship, and order it to enter an inspection orbit. But if a ship doesn't comply?
My gut feeling is that I might not want to destroy civil passenger types, because I have read my post-medieval Terran history, and know how well the Lusitania ultimately worked out for imperial Germany. So those ships I probably want to intercept and board. If they resist by force, I am in my rights to shoot.
If the ship is obviously not a civil passenger type (for example, it has quick-getaway acceleration), then screw sending a gunship with boarding party - I'll missile or zap it.
My sense of it is that space law would probably go roughly along those lines.
I'm of the opinion that Rules of Engagement will be rather intolerant of hijinks of various sorts. Take a look at the "car running down a roadblock in Iraq" situation. Any yahoo can drive a car legally in the US. I'm not sure how it works in Iraq. However, any rational setting will not let that happen in space. If a ship is ignoring my orders, and I have some sort of authority to issue them, then it gets shot at. Period. That's just going to be how it works. Everyone understands that, so anyone who sends a passenger liner through a blockade is going to take the PR hit.
As to the orion, anyone playing with nukes who isn't my friend gets shot at.
Oh, also, in my remark on empires contesting a back-of-beyond planet, I was indeed thinking of interstellar scenarios, because in many cases they are effectively the same, so far as discussions like this one are concerned. Any FTL where you travel a few AU in normal space, do a handwave, then travel a few more AU to reach the destination, is in most respects just interplanetary travel with a handwave.
OK, so I misunderstood. I think it was an attempt to phrase the deployment law.
ROE's vary somewhat from mission to mission, but a few common features come to mind:
1. The military force and the individual members always retain the right to self protection (even to the use of deadly force).
2. So long as the ROE's are correctly applied, soldiers have legal protection. If a car is approaching a checkpoint and is ignoring warnings to stop, I am perfectly in my rights to open fire (or order my troops to open fire). In a similar situation in space, a ship on a crossing or colliding vector is a threat, and if warnings to shear off are ignored then the right of self defense can be invoked. Given the limited manouevrability of spacecraft in the plausible midfuture(tm), the engagement might take place at what would seem to be very long range.
3. Obviously many other factors get considered when writing ROE's. If the attacker has Torchship capability, then they can legitimately move to avoid collision with non torch ships (and send a cutter to board), so burning down an oncoming non torchship would be a big no-no.
4. Since "real" space war will probably resemble an insurgency far more than WWII, ROE's will be written with those situations in mind (i.e dealing with cyber attack, introduction of foreign virus/bacteria/creatures in your ecosystem, assassination of key personnel, currency manipulation and so on).
Tony:
I've finally gotten my hands on the relevant book, and the ALL was operating with 25 microradian beam jitter. Using 1970s tech on an airplane with a gas laser. There's an interesting paper on jitter supression here.
Another interesting one on pointing is here.
Awesum!
From what I see, jitter is considerable reduced by using fast steering mirrors that correct the beam resultant from the laser generator, and multiple stages increases their jitter reduction effects.
25 microradians, wow. That would b enough to make me ditch the whole LTAWS concept...
However, all the designs neglige the fact that with a high-powered BAL, the beam straight from the laser generator would fry a small fast steering mirror by virtue of incident light intensity....and using a larger mirror to compensate (if not directly the main lens) reduces the rate at which the mirror wan steer considerably...
Scifi handwaving to the rescue! What we need is ultra-reflective fast steering mirrors (damn, where's my mirror armor?) or ultra-strong (to counter flexing), very fast and powerful electric motors that counter not only their own vibrations but that of other ship systems...
25 microradians is not half bad, a 1 meter targeting size at 40 km, from an airplane. A space platform in the PMF should be able to do a lot better than that, where 'a lot' can reasonably be adjusted to the needs of the setting.
A bank of laser generators feeding through a bank of mirrors would allow a large amount of laser energy on target without putting too much stress on any individual mirror. This also allows for some laser modules to go down without the ship being put out of action.
If you imagine the ship as a cone with the base covered in mirrors (and the pointed end housing the reactor and drive) then you get the idea.
The problem is where you apply the noise cancelling corrections. As previously pointed out, a small mirror towards the end of the beam path would not be able to withstand the beam energy, whereas a large mirror would be extremely difficult to control. A gang of small mirrors early in the evolution of the beam would work from the energy management perspective, but their respective actuators would create noise for each other. In any case, more mechanical actuators mean more noise in the system
Tony:
You're grasping at straws. Laserstars won't be as good as they are in a diffraction-limited universe. However, let's assume that there is a two order of magnitude improvement in jitter reduction between 1975 on an airplane (ALL) and our laserstar. Running the numbers through my spreadsheet, on a laser with Q=1 and j = 250 nr vs a diffraction-limited laser, I came up with the following.
For a 2-meter laser the effective Q (Spot diameter/diffraction-limited diameter) is 1.29. For a 4-meter mirror, it's 1.92. For a 6.5 m mirror, 2.85. For a 10-meter mirror, it's 4.22. And yes, jitter does get bigger with bigger mirrors. At this level, so much so that it makes little sense to go from 6.5 to 10 meters.
This is with fairly conservative assumptions about jitter. If we go farther, then the numbers get correspondingly better.
Byron:
"You're grasping at straws."
Nope. I'm simply not believing the hype.
vbndrtgf
"A gang of small mirrors early in the evolution of the beam would work from the energy management perspective, but their respective actuators would create noise for each other. In any case, more mechanical actuators mean more noise in the system"
And heat load...and degrade the beam by their individual inefficiencies, multiplied.
"For a 2-meter laser the effective Q (Spot diameter/diffraction-limited diameter) is 1.29. For a 4-meter mirror, it's 1.92. For a 6.5 m mirror, 2.85. For a 10-meter mirror, it's 4.22. And yes, jitter does get bigger with bigger mirrors. At this level, so much so that it makes little sense to go from 6.5 to 10 meters."
You haven't noted that beam intensity goes up with larger mirrors. While a 6.5m mirror will have the same effective range as a 10m mirror, the 10m mirror will make sure the little number of pulses that actually touch the target more likely to destroy it rather than just scratch it. Factoring that in, effective ranges of mirrors will increase until Q becomes larger than the linear relation between mirror diamters and spot size.
"Nope. I'm simply not believing the hype."
Optimistic top-end claims for future adaptive-optics telescopes already make my life hard...these 'astounding figures' better be true (for me) as they'll increase the validity of missiles against laser PD ever more!
For example, I take typical accuracy to be 50milliarcseconds on laser PD. This corresponds to....77nanoradians. This is three orders of magnitude better than the lab-condition tested jitter correctors already!
KraKon:
You haven't noted that beam intensity goes up with larger mirrors. While a 6.5m mirror will have the same effective range as a 10m mirror, the 10m mirror will make sure the little number of pulses that actually touch the target more likely to destroy it rather than just scratch it. Factoring that in, effective ranges of mirrors will increase until Q becomes larger than the linear relation between mirror diamters and spot size.
Can you elaborate on this? I'm really not sure what you're getting at here. Jitter doesn't mean that you usually miss the target. It means that the beam is spread out. I posted the relevant formula in Space Warfare V, towards the bottom. The point is that the 6.5 m mirror is almost as lethal as the 10 m one with this jitter level. I plan to do a more comprehensive analysis later.
Tony:
Nope. I'm simply not believing the hype.
No, I believe grasping at straws is the correct term. I've given a fairly conservative number for jitter and it turned out that fairly conservative laser tech made it plausible. You seem to deny that. So what did I do wrong?
Byron:
"No, I believe grasping at straws is the correct term. I've given a fairly conservative number for jitter and it turned out that fairly conservative laser tech made it plausible. You seem to deny that. So what did I do wrong?"
You totally ignore the practical context. Given those performance numbers, the Air Force thinks it can reliably shoot down a medium to large liquid fueled missile at a range of 600 km. Make the target an inherently much more robust solid fuel rocket, or increase the range, and all bets are off. So, increase the precision by two orders of magnitude. You can reliably shoot down a 20th Century IRBM at a range of 60000 km. But 22nd or 23rd Century targets are likely to be significantly smaller, and much more robust. I won't hazard a guess as to exact performance figures, but I'm willing to bet that they will fall into a range band under 10000 km, for the highest quality, most well maintained weapons. The average weapon? Who knows...a few thousand km? Maybe?
Byron:
"Jitter doesn't mean that you usually miss the target. It means that the beam is spread out."
It means one or the other or both. Jitter in a focusing mirror could mean beam spread. Jitter in a redirecting mirror would mean beam deflection. Jitter throughout the system would impose all kinds of uncertainty in both the beam quality and aim.
"I plan to do a more comprehensive analysis later."
Applying questionably relevant numbers to made up criteria, imposing favorable assumptions.
"Can you elaborate on this? I'm really not sure what you're getting at here. Jitter doesn't mean that you usually miss the target. It means that the beam is spread out. "
What I meant was that even if the 6.5m mirror and the 10m mirror have the same chance of hitting the enemy (with a pulsed laser, this means the number of pulses that hurt vs the number of pulses that will keep on flying forever), the 10m mirror is more effective because the number of pulses that DO connect with the enemy cause more damage by virtue of smaller spot size.
"It means one or the other or both. Jitter in a focusing mirror could mean beam spread. Jitter in a redirecting mirror would mean beam deflection. Jitter throughout the system would impose all kinds of uncertainty in both the beam quality and aim."
Kind of how I understood it (with components shaking around and the lens jumping up and down at the millimeter scale), this causes a CW beam spot to jump around randomly at the target, and jittery pulsed lasers means that the pulses won't be perfectly parallel, but spreading out in a cone like machine gun fire.
"Applying questionably relevant numbers to made up criteria, imposing favorable assumptions."
Give him a break, we all do that! We wouldn't have a discussion involving laserstars at all if it weren't the case.
Tony:
Applying questionably relevant numbers to made up criteria, imposing favorable assumptions.
Yes. Because looking at a variety of mirror sizes and jitter numbers is questionably relevant to the debate.
And I think you just took the prize for that, anyway. We're not looking at shooting down missiles, nor did you apply the two orders of magnitude right. The situations are completely different. Here are some differences off the top of my head:
1. Laser power
We're looking at three orders of magnitude here. ABL is megawatt-class, and we're looking at gigawatt-class.
2. Optics size
ABL's mirror is 62 inches. We're looking at mirrors three times that size or larger.
3. Optical precision
I'm estimating two orders of magnitude here. That's going to be significant
4. Engagement situation
The TBM must be shot down quickly using a CW laser. They only have seconds to shoot with. We're looking at much longer engagement windows, and using pulsed lasers.
KraKon:
"Kind of how I understood it (with components shaking around and the lens jumping up and down at the millimeter scale), this causes a CW beam spot to jump around randomly at the target, and jittery pulsed lasers means that the pulses won't be perfectly parallel, but spreading out in a cone like machine gun fire."
I wonder how many people here even know what a cone of fire is, and what causes it to exist...
"Give him a break, we all do that! We wouldn't have a discussion involving laserstars at all if it weren't the case."
Please allow me to clarify -- that comment wasn't aimed directly at Byron, but at all of the people who think they can quantify capabilities and constraints in technology that hasn't even been invented yet, and other technology that has not been refined to anywhere near the levels implicitly assumed. I've engaged in the numbers game from time to time, but I try to keep my observations and opinions based on qualitative issues. I'm not so interested in how much or how how little, but what, and why.
Maybe the laserstar makes sense, but only under a very narrow set of favorable assumptions. Under a set of more general, less biased assumptions, the multi-capable "fighter-bomber" type of warship makes the most sense, possibly with some class or mission specific optimizations, but hardly to the laserstar extreme.
KraKon:
My equation treats jitter as increasing spot size. However, if what you're saying is correct (and I'm not sure it is. The mirror isn't rigid either.) then jitter will have almost no impact on pulsed lasers. We're looking at a circle with between 2 and 4 times theoretical beam diameter. Under reasonable assumptions about power, and thus spot diameter to do damage, that should fall almost totally on the ship. I really don't see it as happening. It will reduce the drill rate, but the total energy transfer will be about the same.
Re: Byron
I'm not making any presumptions. The ALL and ABL numbers are relevant to megawatt class lasers using a certain beam projection architecture. Their relevance to gigawatt class lasers using different architectures is at best questionable. It's like trying to apply knowledge about 60mm mortars to 16" battleship guns. Both fire projectiles in ballistic arcs at distant targets. Both are also totally different in technical application.
Tony:
Please allow me to clarify -- that comment wasn't aimed directly at Byron, but at all of the people who think they can quantify capabilities and constraints in technology that hasn't even been invented yet, and other technology that has not been refined to anywhere near the levels implicitly assumed.
This is the big problem. You refuse numbers most of the time. If I come up with numbers that are detrimental to your point, you claim that they are irrelevant.
However, without numbers, we know nothing. I'll admit that under high-jitter conditions, big laserstars stop making as much sense, simply becuase a bigger mirror isn't that much better than a small one. While we can't be sure what the future will bring, we can at least guess and do the math.
I'm not making any presumptions. The ALL and ABL numbers are relevant to megawatt class lasers using a certain beam projection architecture. Their relevance to gigawatt class lasers using different architectures is at best questionable. It's like trying to apply knowledge about 60mm mortars to 16" battleship guns. Both fire projectiles in ballistic arcs at distant targets. Both are also totally different in technical application.
Exactly. So why did you make the comparison?
Byron:
"This is the big problem. You refuse numbers most of the time. If I come up with numbers that are detrimental to your point, you claim that they are irrelevant.
However, without numbers, we know nothing. I'll admit that under high-jitter conditions, big laserstars stop making as much sense, simply becuase a bigger mirror isn't that much better than a small one. While we can't be sure what the future will bring, we can at least guess and do the math."
One can know plenty without any -- or at least very few -- numbers. I understand that qualitative analysis is harder, because it relies on both the analyst and the audience to share a knowledge base. I also understand that it is considered "fuzzy" by people who don't like uncertainties. But it isn't invalid, not by a long shot.
My qualitative analysis is that all numbers about future space combat are pure speculation. likewise all caveats about the speculative and biased nature of those numbers, based on real world combat, training, and maintenance experience, are at least tentatively valid, under most circumstances. IOW, I don't care much for the numbers game, because it can at best extablish what is absolutely impossible. At the same time, I'll talk with you all day about the relative qualitative merits of this, that, or the other thing, as long as you understand that either of us can only make very broad guesses about the specifics.
"Exactly. So why did you make the comparison?"
I didn't. I know a lot about 60mm mortars, and something about 16" battlship guns. I know enough to know that making technical comparisons between the two only serves to highlight their differences, rather than their similarities. I certainly wouldn't extrapolate 60mm mortar knowledge in to 16" gun ballistics, internal, external, or terminal. Likewise, I find attempts to extrapolate current megawatt laser technology into gigawatt lasers of the future to be spurious and disingenuous.
Tony:
Actually, I meant the comparison between ABL and laserstars. I understand that the other one was only for illustration.
One can know plenty without any -- or at least very few -- numbers.
Yes, but the use of numbers makes knowledge more certain. Take the progress of laserstars. First, the laser equation says that bigger mirrors are better. So why not put everything into one mirror? It looks great. We're engaging at lightsecond ranges. Until you show up, and start going on about pointing accuracy and jitter and such. I then go in and look at the numbers. It turns out that we can't actually engage at those sort of ranges. Then I look at jitter. Lo and behold, biggger mirrors are significantly less effective under high-jitter conditions. I'll admit that I've never been a huge fan of laserstars as such, and for the start of the PMF, I don't expect to see them.
The point of all this is that using numbers allows us to make better guesses. Taking your arguement to extremes, why don't spacecraft manuver like ships? And don't bring math into this.
I know that you won't go that far, but a guess is better than no numbers at all.
Byron:
"Actually, I meant the comparison between ABL and laserstars. I understand that the other one was only for illustration."
I believe I said that any such comparison was invalid. That's why I didn't use gigawatt laser energies in extrapolating the effects of improvements on ABL aiming precision.
"The point of all this is that using numbers allows us to make better guesses. Taking your arguement to extremes, why don't spacecraft manuver like ships? And don't bring math into this.
I know that you won't go that far, but a guess is better than no numbers at all."
And the point I'm making is that numbers are useless outside oftheir contexts. YOu can't use ABL numbers to think about gigawatt laserstars. And any numbers you attach to laserstars had better be sub-optimal, because wepaons are by their very nature sub-optimal technological systems. (As is any machine, but that's a different discussion.) I'm not questioning the use of numbers, I'm merely questioning the use of highly biased numbers.
Tony:
And any numbers you attach to laserstars had better be sub-optimal, because wepaons are by their very nature sub-optimal technological systems.
That's what the jitter numbers are for. What you've done is forced us to move from spherical cows to elleptical cows. I do understand, but what I've done is tried to do numbers for those sup-optimal situations. The problem you seem to have is that the numbers I'm bringing in don't match what your qualitative analysis has lead you to expect.
Oh, BTW, I didn't come along and do anything. Every objection I've made is in the Bible (AKA Atomic Rockets) on the "conventional" weapons page:
"And don't think that lasers will automatically hit their targets either. There are many factors that can cause a miss. Off the top of his head, Dr. John Schilling mentions:
•Uncertain target location due to finite sensor resolution
•Uncertain target motion due to sensor glint or shape effects
•Sensor boresight error due to finite manufacturing tolerances
•Target motion during sensor integration time
•Analog-to-digital conversion errors of sensor data
•Software errors in fire control system
•Hardware errors in fire control system
•Digital-to-analog conversion errors of gunlaying servo commands
•Target motion during weapon aiming time
•Weapon boresight error due to finite manufacturing tolerances
•Weapon structural distortion due to inertial effects of rapid slew
•Weapon structural distortion due to external or internal vibration
•Weapon structural distortion due to thermal expansion during firing
And we haven't even begun to include target countermeasures..."
A good 50% of these I never brought up, even obliquely. But they're all valid.
OK. However, all of these can be generalized into pointing error. (As an aside, I've never been entirely in agreement with Rick on the "shoot the gun off" because of that.)
We aren't sure how much it will be. This does remove the "each shot always hits" factor, and I'm incorporating it into my next battletrack. However, at a rough guess (and I know I'm pulling these numbers out of think air) I'll say 10x jitter. That puts it at 2.5 microradians for my conservative assumptions. Some quick math indicates that it should be able to hit a 10-meter circle at about 2,000 km. That's not all that bad of accuracy. And that's on the lower end of what I expect.
Re: Byron
I really haven't been paying attention to your work on jitter, except to overoptimisitc assumptions based on ABL numbers. Quite frankly, 2000 km seems a bit underwhelming even for plausible midfuture application. My totally underinformed SWAG would have been 5000 km in the near future, plateauing out at 10000 km some time in the next 500 years.
Tony:
I wouldn't call that assumption overoptomistic. First, it was based on ALL numbers, not ABL. There's about a 25 year difference in the tech. Second, I took 2 orders of magnitude between a 1970s era platform in an atmosphere and a future platform in space. I consider that to be somewhat conservative.
As to 2000 km, that's for a guaranteed hit on a 10-meter wide target. If you are willing to sacrifice certainty, you get more range.
Byron:
"I wouldn't call that assumption overoptomistic. First, it was based on ALL numbers, not ABL. There's about a 25 year difference in the tech. Second, I took 2 orders of magnitude between a 1970s era platform in an atmosphere and a future platform in space. I consider that to be somewhat conservative."
The ALL bears essentially the same realtionship to the ABL that Have Blue had to the first prototype F-117 -- smaller, less powerfull, but effectively demonstrating the technology. So I wouldn't say that the ABL represents a great leap ahead, except in power.
WRT your other point, it is optimistic to apply data on megawatt lasers to gigawatt lasers.
"As to 2000 km, that's for a guaranteed hit on a 10-meter wide target. If you are willing to sacrifice certainty, you get more range."
There's no guaranteed anything in combat. That's one of the qualitative issues I'm talking about. YOu can't precisely quantify the level of uncertainty, but you know it's there, even if your strictly theoretical analysis says that it shouldn't exist.
Tony:
We're dealing with pointing optics. Not with the generators themselves. And I'm certainly not going to find any better numbers anywhere.
As for "guaranteed hit", you're just nitpicking. The laser's pointing accuracy will trace a 10-meter circle at 2000 km. I used 10 meters as what I expect from a typical pseudo-laserstar. That's what I meant. Yes, it may not be 100%, but it's still highly likely.
Byron:
"We're dealing with pointing optics. Not with the generators themselves. And I'm certainly not going to find any better numbers anywhere."
The nature of the generators dictates the nature of the optics. The size and other constraints dictate the smoothbore, relatively short range, low pressure mortar barrel. The size and constraints of the 16" battleship gun dictate a high pressure, rifled barrel. I would expect that gigawatt lasers are going to have significantly different optics modules and optics trains than megawatt lasers do.
So megawatt laser numbers simply aren't applicable. If you don't have any better numbers, you don't have any reliable numbers at all.
"As for "guaranteed hit", you're just nitpicking. The laser's pointing accuracy will trace a 10-meter circle at 2000 km. I used 10 meters as what I expect from a typical pseudo-laserstar. That's what I meant. Yes, it may not be 100%, but it's still highly likely."
I'm not nitpicking at all. I'm making an observation about the relationship between practice and theory. If you want to persist in talking about certainties when it comes to weapons, I'll keep making the point.
Beam jitter and mirror size:
I'm attempting to provide numbers for beam jitter problems. First, methodolgy:
The following equation was used:
BD =(R*SQRT((1.22*L*Q)^2+(J*D*2)^2))/D
BD = beam diameter
R = range
L = wavelength
Q = beam quality (actual beam quality, which is a function mostly of the mirror. I use it below to designate the total diameter/diffraction-limited diameter.)
J = jitter
D = mirror diameter
I have put the numbers in question through my laser spreadsheet. I tested 2, 4, 6.5 and 10 meter mirrors with 250, 100, 50 and 25 nr jitters. Each combination has two numbers. The first is absolute quality (AQ) which is beam diameter/diffraction-limited diameter. The second is relative quality (RQ) which is diameter/the diameter of a diffraction-limited 2 meter mirror. This is to show the actual spot size. They are seperated by a slash, with AQ first.
Please note that I recently found an error in my formula. Previous jitter-limited results were low due to a mistake when converting from diameter to radius. This has been corrected.
I've also figured out the background for the problem with larger mirrors. The spot size will tend to converge on the size of the jitter spot.
Here are the results:
250 nr 100 nr
2m 1.92/1.92 1.20/1.20
4m 3.43/1.71 1.65/0.82
6.5m 5.42/1.67 2.35/0.72
10m 8.26/1.65 3.43/0.69
50 nr 25 nr
2m 1.05/1.05 1.01/1.01
4m 1.20/0.60 1.05/0.53
6.5m 1.46/0.45 1.13/0.35
10m 1.92/0.38 1.29/0.26
The convergence values are as follows:
250 nr: 1.64
100 nr: 0.66
50 nr: 0.33
25 nr: 0.16
Tony:
No, it's more like trying to generalize between say a 5-inch naval gun and a 16-inch nvavl gun. They both have a lot of the same stuff going on, but one is a lot bigger. I'll say that it's fairly applicable, even if the precise engineering is different.
So megawatt laser numbers simply aren't applicable. If you don't have any better numbers, you don't have any reliable numbers at all.
This from the man who used Hubble numbers for pointing accuracy.
Addendum to analyis:
First, I'm willing to send anyone who wants a copy my spreadsheet.
Second, I should specify that the convergence numbers are RQ, and are what would be gotten with an infinitely large mirror.
Byron:
"No, it's more like trying to generalize between say a 5-inch naval gun and a 16-inch nvavl gun. They both have a lot of the same stuff going on, but one is a lot bigger. I'll say that it's fairly applicable, even if the precise engineering is different."
Closer to the difference between a 40mm AA gun and a 16" main armament piece, if you're looking for roughly comparable size differences. And the two aren't technically comparable beyond superficialities.
"This from the man who used Hubble numbers for pointing accuracy."
Yes, for pointing a large structure in microgravity. Which was what a laserstar was, as I understood it at the time. And I only used the numbers to set a real world limit on a constraint, not to feed any kind of analysis.
Tony:
No, the 5-incher was intentional. Yes, a 40 mm might be closer to the right size, but we're dealing with two weapons of fundamentally the same type.
Yes, for pointing a large structure in microgravity. Which was what a laserstar was, as I understood it at the time. And I only used the numbers to set a real world limit on a constraint, not to feed any kind of analysis.
Setting a constraint is analysis. I really don't see where you're coming from on this.
Byron:
"No, the 5-incher was intentional. Yes, a 40 mm might be closer to the right size, but we're dealing with two weapons of fundamentally the same type."
Any two laser weapons are fundamentally the same type of weapon. But they will have significant, and in some cases massive, technical differences in both design and operation, depending on their power, expected range of action, and where and how they are to be mounted. Mortars and battleship guns may have been an extreme example of the possible contrasts, but both mortars and cannons are fundamentally the same thing -- they use chemical energy to project a mass ballistically over a distance. But the technical differences are vast. The technical differences between rifled guns of 40-50 calibers length may seem significantly less, but they're not. Just to highlight the most visibly significant, 40mm (or even 5") AA guns can be installed in any ship big enough to carry their weight, often as a yard modification. A large naval cannon has to have the ship designed for and built around its mounting. Small guns are, in extremis, manually trainable. You need power for large cannon. Small guns can address a wide variety of targets. I could go on and on, but I think the point is made. And the consequent point is that if lasers exist in the real world as weapons, they will have similar distinctions based on size, power, mission, etc. And with those constraints will limits on effectiveness specific to each class and model, which will require specific analysis to address. Numbers won't be interchangeable simply because at some arbitrary level, they're "fundamentally" the same.
"Setting a constraint is analysis. I really don't see where you're coming from on this."
Please. Setting an empirically deduced limit on a constraint is not analysis. It's establishing where a hard stop is in the system, not running the system itself.
Tony:
And this list of influences means that optics for megawatt and gigawatt lasers are different how? I really don't see them as being terribly dissimlar. The best example would be looking at the gun itself and nothing else (mount, ammo handling, etc.)
Please. Setting an empirically deduced limit on a constraint is not analysis. It's establishing where a hard stop is in the system, not running the system itself.
Yes, but when you pull the limit number out of a marginally-relevant example, that is analysis. You're analysis is that it's relevant. And that it's a hard stop. Neither of which are true by definition.
Tony -
Under a set of more general, less biased assumptions, the multi-capable "fighter-bomber" type of warship makes the most sense ...
What, broadly speaking, do you mean by a 'fighter-bomber' type? The term evokes a spacegoing counterpart of an F/A-18, but presumably you intend it only in a fairly figurative sense.
Qualitative analogies can as easily go astray as quantitative ones. Mahan, following an 18th century analogy of three-deckers and 74s, assumed that the most useful battleship would be considerably smaller than the most powerful type. Most of his contemporaries regarded such 'second-class' battleships as expensive, non-capable targets.
To take another example, early-modern naval guns and modern assault rifles have a useful range in most combat situations a good order of magnitude less than their nominal maximum range, whereas dreadnought-era effective gun range turned out to be a substantial fraction of their nominal range, with decisive hits scored around 20,000 yards.
Such differences have, well, a qualitative effect. If the theoretical, spherical-cow range of a laserstar is 100,000 km, it is going to make a huge difference in procurement and tactics if their useful range is 30,000 km, 10,000 km, or 3000 km.
Byron:
"And this list of influences means that optics for megawatt and gigawatt lasers are different how? I really don't see them as being terribly dissimlar. The best example would be looking at the gun itself and nothing else (mount, ammo handling, etc.)"
I couldn't even begin to guess what the specific differences might be. But I can tell you that machines don't scale in linearly. Even something as simple as the gun itself doesn't. For example, a rapid fire antiaircraft gun has a sliding wedge breech block. It uses the propellant case for obturation. The barrel itself is probably monolithic and may be water cooled (up to about 76mm). A large naval gun has an interrupted screw breech. It uses a specially designed obturator built into the breech. The barrel is built up. It would be impractical to apply liquid cooling to such a large gun, except by playin fire hoses on it in an emergency. I would absolutely expect analogous differences in laser weapons based on size and intended application, and would be suprised if there weren't any.
"Yes, but when you pull the limit number out of a marginally-relevant example, that is analysis. You're analysis is that it's relevant. And that it's a hard stop. Neither of which are true by definition."
Actually, I was very clear about the relevance of the example. I pointed out that it was for a scientific instrument under a minimum of operational stress. I also pointed out that weapons under combat stress could not be expected to achieve that level of precision. The relevance was showing that even optimum conditions with the most meticulous care couldn't really provide the performance that people were expecting out of combat conditions. I explicitly invited qualitative analysis on the part of the audience, but I didn't provide it for them.
Rick:
"What, broadly speaking, do you mean by a 'fighter-bomber' type? The term evokes a spacegoing counterpart of an F/A-18, but presumably you intend it only in a fairly figurative sense."
Actually, I deliberately used the term "fighter-bomber" to evoke a vision of both the spacecraft's technical capabilities and operational use. It would be a fighter in that it has both missiles and guns (probably lasers, but maybe particle beams or even projectile throwers). It would be a bomber in that it would be a high energy, probably interplanetary ship, capable of launching KKVs and chemical/nuclear warheads on ballistic trajectories. An F/A-18 is not a bad analogy in the the tactical sense, but I expect the ship to have long range capability and endurance.
That's for the plausible midfuture. If you go operatic on me, I'd suggest a combination of dreadnoughts and cruiser/frigate types, with a supporting array of logistics and transport types to fit the economic and strategic constraints of the setting.
"Qualitative analogies can as easily go astray as quantitative ones. Mahan..."
And it turned out that he was right about the economic nature of total maritime conflict. He just didn't foresee the means in submarines and aircraft. I never fault an analyst on missing the specifics if his intellectual heart is in the right place.
"To take another example, early-modern naval guns and modern assault rifles have a useful range in most combat situations a good order of magnitude less than their nominal maximum range, whereas dreadnought-era effective gun range turned out to be a substantial fraction of their nominal range, with decisive hits scored around 20,000 yards."
And in all cases the real issue was fire control. A man holding a rifle, or a gunner eyeballing down the barrel of a cannon just couldn't establish the kind of precision that more sophisticaed means can. But even in early modern times black powder mortars were effective at their maximum ranges, because more precise means of establishing range to the target could be used on land, and both the target and the gun were sitting still. Likewise, while a man with an assault rifle isn't good much past 300 m, a man with a machinegun on a tripod can be effective out to 1200 m or so, because he's firing from a steadier platform and relying on dispersion of a large number of rounds to hit his target.
"Such differences have, well, a qualitative effect. If the theoretical, spherical-cow range of a laserstar is 100,000 km, it is going to make a huge difference in procurement and tactics if their useful range is 30,000 km, 10,000 km, or 3000 km."
Unquestionably. I never doubted that a laser could be nominally effective at very long ranges. I was just questioning it's ability to reliably hit anything.
My purely gut feeling is that both 'fighter-bomber type' and 'combination of dreadnoughts and cruiser/frigate types' sound way too much like familiar recent era archetypes.
Having said that I realize it depends heavily on the degree of generalization intended. In an operatic setting you'll almost certainly want some forces that can take on all comers in highest intensity situations, and other forces that can do all the grunt work (patrol, local intimidation, whatever) more cheaply with 'sufficient' force.
How that maps onto vehicles can vary widely.
What I am saying is that ability to adjust production rates will not factor highly into a company's choice of which harvesting method to use. If, however, the method that turns out to be the most efficient for other reasons, happens to also easily allow adjustable production rates anyway, then companies will of course make use of this feature.
Umm, oops. That's what happens when you close a thread, go "wait, I had something to say about that", then try to reopen the thread and post without checking you're in the right one!
Rick:
"My purely gut feeling is that both 'fighter-bomber type' and 'combination of dreadnoughts and cruiser/frigate types' sound way too much like familiar recent era archetypes.
Having said that I realize it depends heavily on the degree of generalization intended. In an operatic setting you'll almost certainly want some forces that can take on all comers in highest intensity situations, and other forces that can do all the grunt work (patrol, local intimidation, whatever) more cheaply with 'sufficient' force.
How that maps onto vehicles can vary widely."
With all due respect, I think we've let the "space is different" trope overwhelm our thinking. I tend to view warfare as an economic and political exercise that has its own logic, independent of time and place. Or, to put it another way, local conditions (in both time and space) affect the means, but war is still war, and the "paradoxical logic" (as Edward Luttwak puts it) of strategy still dominates.
So I don't think it's all that wrong to use familiar terms to make analogies about future possibilities, as long as we're clear about the intent. Fighter/bomber is meant to evoke the idea of flexibility and mission configurability, and maybe a general idea that such a craft would be as big as it needs to be, but no bigger. In the plausible midfuture, space warships are likely to be expensive and rare, so they will need to be flexible. Dreadnought, cruiser, and frigate are meant to evoke a certain set of mission requirements more than size or configuration. In an operatic future, space warships would still be expensive, but much more common, so built-in mission optimizations would make sense.
Strategic conceptions can lend themselves to a variety of technical expressions.
For example, in several periods during the galley era, the same galleys could be deployed for battle-force missions and cruiser missions. For the battle force they would be sent in large squadrons, and with relatively more deck troops; for cruiser missions individually or in small squadrons, and with relatively more rowers.
Semi-modular vehicles could easily lend themselves to a roughly comparable approach. More modular tech could eliminate the whole notion of permanent configurations, in favor of 'consists' of modules, a term swiped from railroading.
I'm not particularly arguing for either of these concepts, but I think they (and others) need to be part of the mental mix, because terms like 'fighter-bomber' or 'cruiser' carry, along with their conceptual meanings, an awful lot of connotative baggage.
Semi-modular vehicles could easily lend themselves to a roughly comparable approach. More modular tech could eliminate the whole notion of permanent configurations, in favor of 'consists' of modules, a term swiped from railroading.
Omnimechs!
I've read that the Navy is working on this idea for the next generation of surface combatants. We'll see how it works out.
Rick:
"Strategic conceptions can lend themselves to a variety of technical expressions.
For example, in several periods during the galley era, the same galleys could be deployed for battle-force missions and cruiser missions. For the battle force they would be sent in large squadrons, and with relatively more deck troops; for cruiser missions individually or in small squadrons, and with relatively more rowers."
Certainly. But one has to have an idea why things happen the way they do. Taking the Athenian navy, for example, there were engineering and economic limitations that made the trireme the optimal design for all missions. The trireme was about the largest vessel that could be made as fast as the Athenian admirals wanted their ships to move, while not being too big for scouting and patrol missions. Also, the trireme was funded by private sponsorship, so no one ship could be too big.
Fast forward to the Venetian Republic, galleys could be made somewhat bigger and robust than the trireme and still be practical. There was also a different rowing scheme, the need to mount guns, and better sailing technology. Finally, and probably most importantly in the Venetian context, while most galleys were of a standard "cruiser" type, state funding allowed the building of a few large squadron and fleet flag galleys, as well as galleasses.
If one wants a navy full of cruisers, one could certainly do so. It does need to be justifiable by economic and strategic conditions.
"Semi-modular vehicles could easily lend themselves to a roughly comparable approach. More modular tech could eliminate the whole notion of permanent configurations, in favor of 'consists' of modules, a term swiped from railroading.
I'm not particularly arguing for either of these concepts, but I think they (and others) need to be part of the mental mix, because terms like 'fighter-bomber' or 'cruiser' carry, along with their conceptual meanings, an awful lot of connotative baggage.
No reason not to take advantage of that baggage, if it's applicable. Fighter-bomber is deliberately meant to be evocative of modularity and mission-oriented configuration. Also, it gives a good idea of the potential weapon loadouts, including guns, self-propelled missiles, and ballistic missiles. There's nothing in the naval lexicon that really fits, and (IMO at least) we should be loathe to coin terminology simply for the purpose of avoiding connotation.
WRT operatic settings, naval types make more sense as descriptors. Cruiser is probably better than frigate, because it is strictly reliant on intended function, but both are applicable for independent patrol and scouting vessels. Maybe dreadnought was a bad choice, so let's use battleship which, like the cruiser, is a functional descriptor. In any case, there's no need to coin new terminology here either, as long as we're clear with each other that we're talking about function dictating form.
Mission decriptors like interceptor, cruiser, battleship, cargo transport, fighter-bomber, or even baseship are just placeholders; they discribe missions or capabilities of types of ships. What those ships will actually be called, and what range of capabilities they will embody, we can only guess at, but we can still try. What do we need to have them do, instead of what we want them to do might be a good place to start.
Ferrell
we should be loathe to coin terminology simply for the purpose of avoiding connotation.
I tend to disagree, for story-centric reasons. The common practice of having 25th century forces with 1900 era type names is one of my long-standing grumps, as is 25th century service people speaking in acronyms.
Conceptual discussion is a somewhat different matter, but in general I think spacecraft are different enough from either ships or aircraft that analogies drawn from the latter are apt to be misleading.
I tend to disagree, for story-centric reasons. The common practice of having 25th century forces with 1900 era type names is one of my long-standing grumps, as is 25th century service people speaking in acronyms.
Yeah. It's ridiculous to have Thor speaking in King James English but it's also ridiculous to bring in all sorts of modern slang, idioms, and turns of phrase.
What would you want to call someone in ancient Greece who sides with an invader and serves him openly? Quisling's a good word except it mentally jarring if you have any understanding of where it came from. Fine, call him a turncoat, only coats hadn't been invented yet! If you're writing a story set in pre-columbian America you don't want your Aztec king upon accepting a gift to say "Don't look a gift horse in the mouth."
But if you get too caught up in this, you go mad. Strictly speaking, all of English is invented after the fact in these stories and you could look at it as the author "translating" it for a modern audience. So if your story features an officious priest trying to sanitize the old myths for young ears, it might be the most accurate translation to say he is bowdlerizing the myths!
I do agree that using contemporary terms in the far future really grates. Concepts will translate like "I want to know what's going on" or "where is he strong but precarious, let us attack there" but it would sound funny to hear Starlord Smith ask for a "sitrep" or pull up a powerpoint and talk about hitting the enemies in their "centers of gravity." We quote Sun Tzu thousands of years later but Pentagonese doesn't have that same timeless feeling. I can accept 25th century Starlord talking about "fatal terrain" long before I can believe him talking about C^3 or C^4I or C^4ISR (command, control, communications, computers, intelligence, surveillance, and reconnaissance). I mean for Xod's sake, why not just call it *.* because it accounts for everything under the sun.
Conceptual discussion is a somewhat different matter, but in general I think spacecraft are different enough from either ships or aircraft that analogies drawn from the latter are apt to be misleading.
The lack of horizon and lack of stealth -- it's weird!
Rick:
"I tend to disagree, for story-centric reasons. The common practice of having 25th century forces with 1900 era type names is one of my long-standing grumps, as is 25th century service people speaking in acronyms."
I have to repsectfully ask, might this not be even the slightest bit of an overreaction on your part? "Frigate" has been with us for at least 500 years, originally referring to a light galleas. Through many different changes in technology, it has always referred to a relatively light and maneuverable patrol/scouting/escort vessel. It looks to be good for at least a couple more centuries. I don't see why even more neutral, functional type descriptors, like "cruiser" or "battleship" shouldn't be good for at least the next half millenium. For story-centric reasons the author should make sure the name fits a ship performing a historically analogous function (frigates scouting or patrolling, cruisers holding down distant posts, battleships in the main battle fleet(s)). But beyond that, there's no compelling reason to try to find new terminology.
"Conceptual discussion is a somewhat different matter, but in general I think spacecraft are different enough from either ships or aircraft that analogies drawn from the latter are apt to be misleading."
I'm just not seeing it. Warships in the plausible midfuture will indeed probably be more like aerial fighter-bombers than anything else (and will probably be manned by personnel drawing their traditions from air forces, if not air force personnel themselves). As your setting gets more operatic, with time and light horizons growing (especially in an interstellar setting), the logic and need behind the old naval types becomes pretty compelling, as does the need for a more naval type of industrial, administrative, and tactical organization.
jollyreaper:
"What would you want to call someone in ancient Greece who sides with an invader and serves him openly?..."
"Medizing" is the anglicization of the historical term. We also have many instances of "X lover". Going by these examples, I think an SF author would be pretty safe in finding a term referring to the hated group.
"I do agree that using contemporary terms in the far future really grates. Concepts will translate like "I want to know what's going on" or "where is he strong but precarious, let us attack there" but it would sound funny to hear Starlord Smith ask for a "sitrep" or pull up a powerpoint and talk about hitting the enemies in their "centers of gravity." We quote Sun Tzu thousands of years later but Pentagonese doesn't have that same timeless feeling. I can accept 25th century Starlord talking about "fatal terrain" long before I can believe him talking about C^3 or C^4I or C^4ISR (command, control, communications, computers, intelligence, surveillance, and reconnaissance). I mean for Xod's sake, why not just call it *.* because it accounts for everything under the sun."
I'm not sure what I think about this. After 400 years we still use the terms "battalion" and "company" to mean roughly the same things. "Brigade" is about as old. And "colonel" is older than that. I wouldn't be surprised if those terms aren't good for another 500 years, since they represent pretty fundamental concepts about modern military hierarchies. Also note that in the 18th and 19th centuries there was a Classical revival in terminology, with some units in some armies being officially designated "legions".
On the other hand, it's hard to see how current operational terminology would fit into a future setting, unless the state of the art just stagnates. But on the other hand (doing my best Reb Tevye), they still talk about coup d'oeil (referring to a discerning eye for terrain). I think maybe whatever the author is comfortable with is okay, as long as he remembers that his own made-up jargon is going to be just as confusing to readers as any obscure current jargon he could use.
"The lack of horizon and lack of stealth -- it's weird!"
The lack of visible horizon and stealth is in theory only. We send probes with only moderately magnified cameras to distant planets because they can resolve things that even the most powerful and precise telescopes on Earth or in orbit can't. Likewise, while a large telescope with an infrared detector could in theory detect any engine burn in the solar system, it remains a large telescope with a very narrow field of view and very slow scan rate. It wouldtake a lot of effort to even monitor just the space around a few planets. Tracking ships between planets? A lot more effort than some people appear to think.
On top of that is the reality of a time horizon. It may take only 10-20 minutes to receive a signal from Mars, but even that is too slow for tactical decisionmaking, if the adversary has a live human being on the spot, with authority to act. So any disputed space will probably have squadrons of all the disputants on the spot.
The more operatic things get, especially if one goes interstellar, and you get a situation much like early modern Mediterranean galley warfare. Fleets would have large numbers of small scout vessels out looking for the enemy fleet(s), while the main battle fleet(s) occupy(ies) a guard position, waiting for news of the enemy to be carried back. Then the time between an enemy sighting and a report of that sighting reaching the admiral would have to be taken into account. One imagines two fleets bent on fighting gradually approaching each other, with scouting data becoming more and more solid, until they meet in combat. A fleet wishing to evade a battle could game the reporting delay to always stay a step ahead.
I remember reading something David Drake wrote on this:
One of the problems when you’re writing of either the past or the future is ‘How much should I translate?’ I don’t mean simply language: there’s a whole complex of things that people within any society take for granted but which vary between societies. (But language too: I had somebody complain that the Arthurian soldiers in The Dragon Lord talked like modern soldiers. My reaction to this was that I could write the soldiers’ dialogue in Latin, but the complainant couldn’t read it; and if I’m going to translate into English, why on Earth wouldn’t I translate into the type of English the same sort of men speak today?)
(From the prologue to The Far Side of the Stars.
The lack of visible horizon and stealth is in theory only.
Not really. You seem to be getting confused on this. Luke already did the math, but since you won't accept that, here's my take:
While it is true that scan rates might be low enough that you won't instantly see everyone, scan rates will be high enough to detect any strategically significant burns. If the drives operate on miligee levels, and thus burn times are measured in days or weeks, completing a full scan every 6 hours is perfectly acceptable. If the drives are more powerful, with burn times on the order of hours, they are also correspondingly more bright, which renders detection easier.
The biggest issue is timescale. When transit times are measured in months, hour detection lags are perfectly acceptable.
We send probes with only moderately magnified cameras to distant planets because they can resolve things that even the most powerful and precise telescopes on Earth or in orbit can't.
That won't be an issue here. If it was, I couldn't see any stars at night.
Likewise, while a large telescope with an infrared detector could in theory detect any engine burn in the solar system, it remains a large telescope with a very narrow field of view and very slow scan rate.
See above. Plus, I'd immagine that most ships will be making their burns at a planet.
It would take a lot of effort to even monitor just the space around a few planets. Tracking ships between planets? A lot more effort than some people appear to think.
Not really. It's actually quite simple. Point one telescope at each planet of interest. Have a few telescopes go around and check on the ships in transit. Any burn will be seen long before it can make much difference.
On top of that is the reality of a time horizon. It may take only 10-20 minutes to receive a signal from Mars, but even that is too slow for tactical decisionmaking, if the adversary has a live human being on the spot, with authority to act. So any disputed space will probably have squadrons of all the disputants on the spot.
Not this again. I don't think that decision-making will be that time-sensitive. My drones will have shootback routines built in. Everyone will know this. They will have no excuse if they start zapping and get zapped back.
Byron:
"But language too: I had somebody complain that the Arthurian soldiers in The Dragon Lord talked like modern soldiers. My reaction to this was that I could write the soldiers’ dialogue in Latin, but the complainant couldn’t read it; and if I’m going to translate into English, why on Earth wouldn’t I translate into the type of English the same sort of men speak today?"
Hehe. How many new ways can one find to say:
"The Capatain's an idiot."
"The Sergeant's insane."
"The chow sucks."
"You smell like sh!t."
"I'd fvck the dogsh!t out of her."
"If I have to look at your face one more day, I'm gonna lose it."
?
if I’m going to translate into English, why on Earth wouldn’t I translate into the type of English the same sort of men speak today?)
I really liked Pressfield's Gates of Fire and he did lots of little touches. The framing story is the battle of the 300 told by a gravely wounded survivor. He's relating the story to a historian in the court of Xerxes. The soldiers are earthy and swear and we're given a hint to what the four-letter words are in the original greek, translated to persian for the Emperor's understanding. But there are a few facepalms like including tomatoes and talking about a wall having a blueprint. I think that has to be something that just slipped in late at night and was missed by the editor.
Having the grunts focused on food, sleep, gambling, and complaining about everything is authentic. Complaining about the bastards who have it better off back away from the fighting is authentic. Calling them REMF's would break immersion, even if the sentiment is entirely the same.
The more subtle form of inauthenticity is giving the characters modern morality. If you want someone to be condemning slavery in Rome, you should turn to the contemporary critics and use their arguments but not use any modern conceptions, not unless it's time travel. In terms of sexual politics, Romans weren't supposed to have a concept of being gay or that homosexuality was demeaning; rather, it was masculine to be the top and it was demeaning to be the bottom, be it man or woman.
There's whole writeups on values dissonance on ye evile website.
Byron:
"Not really. You seem to be getting confused on this. Luke already did the math,"
I've really been trying hard to avoid saying this, but screw it: since when is Luke the Oracle? Can somebody tell me that? AFAICT, he's just another Guy on the Internet, with certain enthusiasms.
"completing a full scan every 6 hours is perfectly acceptable."
Impossible. I presume you're going off of Ken Burnside's numbers on the Atomic Rockets "Space War: Detection" page. While I don't doubt his spherical geometry, his exposure times are ridiculously low. IR CCD sensors just aren't that sensitive. You have to concentrate a lot of light on them to pick up small, concentrated variations of even thousands of degrees (WRT the background) at interplanetary ranges.
Remember, we're dealing with the inverse square law here -- something quite hot at a few hundred or thousand kilometers reduces to a very mild heat flux at tens or hundreds of millions. With a decent telescope you can track an identified target without much trouble. But you're not going to find it with a rapid sky scan, even with cryogenically cooled IR sensors.
"The biggest issue is timescale. When transit times are measured in months, hour detection lags are perfectly acceptable."
See above. If you're relying on sky sweeps that will actually pick up the heat given off by relatively low energy drives, the odds are overwhelmingly likely that the spacecraft of interest won't be in the field of view of any of your snapshots.
"That won't be an issue here. If it was, I couldn't see any stars at night."
Tell us, why is it then that people can't see spacecraft propulsion burns in orbit with their naked eyes? Also, shouldn't the average person should be able to see with the naked eye the several ion motors currently in operation throughout the solar system?
"See above. Plus, I'd immagine that most ships will be making their burns at a planet."
Which is why you have to keep a pretty good telescope pointed at the planet, to detect departures. Of course, if they're relying on high impulse rocketry and do their burn on the far side of a planet...
Or you could just place a comprehensive set of surveillance satellites in the planetary space of interest. Then the other guy has to perform an act of war to stop you from watching him.
"Not really. It's actually quite simple. Point one telescope at each planet of interest. Have a few telescopes go around and check on the ships in transit. Any burn will be seen long before it can make much difference."
You've got the method correct, as far as you take it, but the more energetic the drive technology, the more constantly you're going to have to watch transiting vessels, because they have a greater capability to maneuver off of a given trajectory. Also, if you're worried about KKV launches, you'll have to observe constantly, with really powerful telescopes.
"Not this again. I don't think that decision-making will be that time-sensitive. My drones will have shootback routines built in. Everyone will know this. They will have no excuse if they start zapping and get zapped back."
Yes, this again -- and as often as it takes for the point to sink in. Your attitude towards positive control is positively (every possible pun absolutely intended) incredible. Even the Soviets kept men in the loop on reactions to attacks.
Tony:
I've really been trying hard to avoid saying this, but screw it: since when is Luke the Oracle? Can somebody tell me that? AFAICT, he's just another Guy on the Internet, with certain enthusiasms.
No, he's not the oracle. However, he did do the math on detection and sensitivity. It's posted somewhere above.
As to 6 hours, that was a top-of-the-head number.
See above. If you're relying on sky sweeps that will actually pick up the heat given off by relatively low energy drives, the odds are overwhelmingly likely that the spacecraft of interest won't be in the field of view of any of your snapshots.
Relatively low energy? What does that mean? They may be low-thrust, but we're still looking at Gigawatt levels of radiated power. Plus, the radiators will be giving off three times as much as the drive does.
Tell us, why is it then that people can't see spacecraft propulsion burns in orbit with their naked eyes? Also, shouldn't the average person should be able to see with the naked eye the several ion motors currently in operation throughout the solar system?
Due to lack of intensity on our end. Plus, most burns in orbit are quite small. Resolution isn't the only thing that matters for detection. You don't have to be able to resolve your target as a pixel.
Which is why you have to keep a pretty good telescope pointed at the planet, to detect departures. Of course, if they're relying on high impulse rocketry and do their burn on the far side of a planet...
Then it takes them a couple extra months to get where they're going. That's going to be significant. Plus, they have to use a unique ship, and your intel people should notice that. These telescopes aren't meant to be used in isolation. Not to mention that observation posts were invented to deal with exactly this problem.
You've got the method correct, as far as you take it, but the more energetic the drive technology, the more constantly you're going to have to watch transiting vessels, because they have a greater capability to maneuver off of a given trajectory. Also, if you're worried about KKV launches, you'll have to observe constantly, with really powerful telescopes.
Yes, but the more energetic the drive, the less expensive the equipment required to watch for it. If an uncooled CCD can see the burn (which I think is likely for torchships) then I can monitor the entire sky cheaply and constantly.
Your attitude towards positive control is positively (every possible pun absolutely intended) incredible. Even the Soviets kept men in the loop on reactions to attacks.
Yes. Because someone shooting a laser at me might just have had an accident. That makes perfect sense.
I'm not saying that this would be on at all times. I'm saying that I'd enable it during a staring contest. They know it's on, and it's as foolproof as I can make it. It shoots directly down the beam that struck it. Nothing more.
Maybe I'm somewhat less concerned about this then you are. I don't think it's entirely unreasonable. There are tradeoffs either way.
Ok, I've noticed something: some people here don't totally understand what the term "Whole Sky" scan means; this is an astronomical term meaning viewing the sky horizon-to-horizon, east to west, north to south, from dusk to dawn. The way some people are using it to mean a scan of space from orbit still isn't quite right either. For one thing, a giant thermonuclear bonfire sits in the middle of the solar system and it will either take several months to do a 'whole sky' scan, or that you need to have several observation platforms in solar orbit.
Now, to illustrate something else; the difficulty of keeping track of objects in space.
1) scanning space; (some arbitrary numbers)a telescope that has a one degree by one degree field of vision that takes 6 seconds per exposure will take 216 hours to make one global scan.
2) if there are 300 known spacecraft operating in the system, you will need 300 telescopes at a minimum just to track them, and many more to cover any 'blind spot' (remember the sun?), plus however many you think you will need to scan for 'unknowns' be it ships, kinetics, asteroids, or comets.
Just something to think about :>
Ferrell
Rick: Well, that was different: Blogger shuffled me off to a screen that said 801-757 of 757 when I tried to post a comment. I still haven't seen the comment so I don't know if it's in limbo or just plain gone.
Ferrell
Byron:
"No, he's not the oracle. However, he did do the math on detection and sensitivity. It's posted somewhere above."
Based on invalid assumptions. Even chilled IR sensors just aren't that sensitive. Let's say you can manage to get CCD resolution down to 1/10000 degree/pixel. At 25 million km, a pixel has an area of 1904 sq/km. So a 1000 x 1000 m radiating surface covers just a little bit more than a half a percent of the pixel. Now, how hot do you think it's going to have to be to exceed the sensor's detection threshold? Above my optics paygrade, but my general engineering sense says you're going to need a pretty big and hard to steer scope to concentrate enough light to get reliable data at even moderate interplanetary ranges.
"Relatively low energy? What does that mean?"
Compared to torch drives. But looking at the above, those may even be a bit hard to detect, without either a lot of expensive instruments.
"Due to lack of intensity on our end. Plus, most burns in orbit are quite small. Resolution isn't the only thing that matters for detection. You don't have to be able to resolve your target as a pixel."
Nope, but signal size compared to pixel size has something to do with it, else your sensors would never see anything but a gray fog created by all the stars and galaxies in the bockground.
"Then it takes them a couple extra months to get where they're going. That's going to be significant. Plus, they have to use a unique ship, and your intel people should notice that. These telescopes aren't meant to be used in isolation. Not to mention that observation posts were invented to deal with exactly this problem."
Let's put our thinking caps on, okay? You use the high impulse kick to execute the departure, then turn on your low impulse interplanetary drive when you're 10 or so million km away. I like the idea of observation posts, but I think a surveillance satellite constellation with comprehensive coverage would be better. Still, if we get far enough down the road where whole planets control their own space, the tactic might work.
"Yes, but the more energetic the drive, the less expensive the equipment required to watch for it. If an uncooled CCD can see the burn (which I think is likely for torchships) then I can monitor the entire sky cheaply and constantly."
See above. You can monitor the sky cheaply, or you can monitor it constantly. Not both, AFAICT.
"Yes. Because someone shooting a laser at me might just have had an accident. That makes perfect sense.
I'm not saying that this would be on at all times. I'm saying that I'd enable it during a staring contest. They know it's on, and it's as foolproof as I can make it. It shoots directly down the beam that struck it. Nothing more.
Maybe I'm somewhat less concerned about this then you are. I don't think it's entirely unreasonable. There are tradeoffs either way."
Why does the enemy only have lasers? And crisis situations are the ones in which positive human control is the most critical.
Tony:
"It may take only 10-20 minutes to receive a signal from Mars, but even that is too slow for tactical decisionmaking, if the adversary has a live human being on the spot, with authority to act."
If you don't already have someone around Mars, then how long the signal takes to arrive is irrelevant - even if you had magical FTL communication, it would take you far longer than 10-20 minutes to send a response force across interplanetary space.
"Or you could just place a comprehensive set of surveillance satellites in the planetary space of interest. Then the other guy has to perform an act of war to stop you from watching him."
That only works if you already have legal sovereignity over the other planet. If you don't, then they could very reasonably argue that putting spy satellites in their orbit was an act of war, and they merely responded in kind.
And if you were already at war, then the only "spy satellites" worth using are the ones strong enough to defend themselves. Which most likely means crewed cruisers.
Byron:
"Yes. Because someone shooting a laser at me might just have had an accident. That makes perfect sense."
There were several times in the Cold War that one or the other's computer reported a missile launch, and then on closer inspection it turned out to be a false alarm for one reason or another.
Back on topic: orbital combat is a significantly more complicated environment than deep space combat, for several reasons (curved space, orbital clutter, ground clutter and surface-to-orbit defenses, inability to see through the planet), so even if drones suffice for deep space interception, I would not rely on them for laying siege to an enemy planet.
"They know it's on, and it's as foolproof as I can make it."
If you think something is foolproof, that's just because you haven't yet found a sufficiently big fool.
Ferrell:
"Well, that was different: Blogger shuffled me off to a screen that said 801-757 of 757 when I tried to post a comment."
All the comments being rescued from the spam filter are messing up Blogger's post counts somehow. The "real" number of posts in the thread is 757 or thereabouts. The posts are still there, you just have to manually click back to the second-last page rather than the last page.
Tony:
"You can monitor the sky cheaply, or you can monitor it constantly. Not both, AFAICT."
In that case, let's go with constantly. When has the military ever cared about being cheap? You only need one telescope array per planet, so you can afford to splurge on it. It's still going to cost less than, you know, warships.
I have to respectfully ask, might this not be even the slightest bit of an overreaction on your part? "Frigate" has been with us for at least 500 years,
Here's the entry on Frigate from my old Tough Guide to the Known Galaxy. And, likewise, Battle Cruiser.
'Frigates' in future era space service would not bother me, precisely because the word has taken on so much life of its own. 'Battlecruisers' arguably have the same status. On the other hand, LRP-3B (for Long Range Patrol) would make my plaus-O-meter jump.
The more general answer to this question is that I'm giving my preference (or bias), and reason for same. It might be useful background information to know that I was a fan of Firefly, but was never even tempted to try the (rebooted) Battlestar Galactica, even after reading positive commentary. I just wasn't up for USN carrier ops in SPAAACE, even if well done.
Having the grunts focused on food, sleep, gambling, and complaining about everything is authentic. Complaining about the bastards who have it better off back away from the fighting is authentic. Calling them REMF's would break immersion, even if the sentiment is entirely the same.
How people of other eras ought to speak on the page is a longstanding matter of discussion - and I'll take it on in a (near) future front page post.
My impression of David Drake is that his readership doesn't just want rough, soldierly language - for that readership, characters sounding exactly like recent era US grunts is a feature, not a bug.
I've really been trying hard to avoid saying this, but screw it: since when is Luke the Oracle?
Maybe because he sounds like he knows what he is talking about?
And I'll go ahead and say what I've been trying to avoid - why such a friggin aggressive tone?
I welcome challenge and disagreement in these comment threads - well, human nature being what it is, I don't exactly welcome it, but I'll leave it to the commenter community to decide whether I'm too heavy handed.
What I don't much welcome is a sneering tone I've seen a few times - calling another commenter 'young jedi' in a clearly condescending way, or accusing a (very longtime!) commenter of being a troll. That stuff gets aggravating, and does not reinforce arguments.
The more general answer to this question is that I'm giving my preference (or bias), and reason for same. It might be useful background information to know that I was a fan of Firefly, but was never even tempted to try the (rebooted) Battlestar Galactica, even after reading positive commentary. I just wasn't up for USN carrier ops in SPAAACE, even if well done.
I don't know if you read the series bible for the new show but it's even worse than you'd think. There's a whole section detailing carrier ops. The following is pulled from the BSG wiki explaining the phrase "call the ball."
The "ball" refers to the arrangement of crossed navigational lights at the lip of the landing bay, and/or the visual cue on a cockpit display (as seen in Kat's Viper in "Act of Contrition"). The pilot would use this to adjust his/her glideslope for a proper approach into the flight pod. The phrase "I have the ball" informs the LSO that the pilot has acquired this visual cue and is beginning the final approach.
Glideslope. GLIDESLOPE! IN SPAAAACE!!!
May as well have your damn crew-served machine-laser use special lasing crystals that are consumed with each shot and need to be fed into the firing chamber via a disintegrating belt.
How people of other eras ought to speak on the page is a longstanding matter of discussion - and I'll take it on in a (near) future front page post.
I'll be interested in reading that! On one hand, you have ridiculous crap like making up new words for minutes and seconds and curses that's just silly (centons, yarens, frak), but on the other hand you have modern conventions showing up in the most jarring fashion like the hearing "september" and "monday" in LOTR, especially in light of the fact that he'd already worked up complicated calendars for the various races!
Rick:
"Here's the entry on Frigate from my old Tough Guide to the Known Galaxy. And, likewise, Battle Cruiser."
While we're on the subject, I would like to quibble with a part of your TRADE FEDERATION entry.
"The need to patrol extensive Trade routes as well as fight stand-up battles make BATTLE CRUISERS a rather sensible choice as capital ships for active Trade Federations. Indeed, this may explain the general prevalence of Battle Cruisers throughout the KNOWN GALAXY. Perhaps everyone builds them - even when ill-suited to local requirements - because the type is associated with the powerful Trade Federation fleets."
I counter that this will not lead people will not build battlecruisers when they're inappropiate to local requirements, at least, not past the first few years (particularly if a war breaks out). Rather, what people would do is build whatever ships are appropiate to local conditions, but just call them battlecruisers. "No, it's not a battleship! It's just the world's biggest and most heavily armed battlecruiser! Really!"
Jollyreaper:
"On one hand, you have ridiculous crap like making up new words for minutes and seconds and curses that's just silly (centons, yarens, frak),"
Time measurements seem to have a pretty long shelf life - we're still using the "week", based on a completely arbitrary number of days, thousands of years after its introduction. Granted, it has religious support to keep it going.
Our current units like seconds and minutes are so ubiquitous that they aren't likely to go away anytime soon - that would require a complete redesign of huge amounts of equipment and render old data hard to work with, for no particularly good reason.
It's possible, however, that in space and on other planets - where time units based on Earth days or years aren't so useful - people will start talking more in terms of kiloseconds and megaseconds, which have the convenience of a metric system. (For what it's worth, 100 kiloseconds = 27 hours, 46 minutes, and 40 seconds.) But then again settlers are likely to develop their own calendar based on local conditions. And there are reasons to keep using existing measurements, at least at first - we're used to them. And human physiology could get wonky if you try to use sleep cycles vastly different from 24 hours, though I'm sure there's some room for fudging, so that's a reason to keep the Earth day as a unit no matter where we go.
As for curse words, though? Like all slang, it's entirely natural for the vocabulary of explitives to renew itself every few generations. We might not be able to predict what curse words people will be using three hundred years from now, but I'll bet you that most of them will not be ones that are common, or possibly even extant, today. If you do render them with present-day curse words, then that's just the translation convention at work. It does, however, seem a little hollow when it's fairly obvious that the author "really" used made-up curse words as a form of censorship to avoid offending modern readers. At least if the curse is supposed to be so offensive in the characters' culture, make them act like it in-story.
Rick:
"but on the other hand you have modern conventions showing up in the most jarring fashion like the hearing "september" and "monday" in LOTR,"
September has been around with essentially the modern meaning since the establishment of the Julian calendar in 45 BC. It is a perfectly reasonable time measure in any setting meant to evoke the feel of medieval Europe. (It is a little more dubious in a setting that's only aesthetically similar to medieval Europe while not actually being in medieval Europe, like LoTR.) Mind you, the exact modern meaning only came with the introduction of the Gregorian calendar, which only took place after the middle ages had ended by most counts. But the difference would be a few days.
The seven-day week, as I said above, has been around even longer, and would definitely be observed in medieval Europe. Given Tolkien was a Christian and intended for the supreme deity in his fictional religion to "really" be the Christian god, it's not implausible that some sort of commandment or tradition for seven-day weeks would have worked its way into Middle-Earth's timekeeping. So they'd have mondays. They might not call them mondays, but that's the translation convention for you. Now, if a hobbit were to talk about mondays with the same attitude that many working class people have about mondays today (resignation at having to return to work once again after a two-day rest period), then that would be more jarring.
"especially in light of the fact that he'd already worked up complicated calendars for the various races!"
My recommendation would have been to use the speakers' native calendar in the main text, then including a footnote indicating a conversion to familiar units so readers don't have to flip all the way to an appendix.
Oops, that last bit should have been directed at Jollyreaper as well, not Rick. Sorry!
Also sorry about making four separate posts. Blogger's fault on that one. Stupid post size limits :(
Milo:
"If you don't already have someone around Mars..."
In the plausible midfuture you will have somebody around Mars, or you aren't in the game to begin with.
"That only works if you already have legal sovereignity over the other planet. If you don't, then they could very reasonably argue that putting spy satellites in their orbit was an act of war, and they merely responded in kind."
Nobody has total legal sovereignty over Earth, yet several powers have surveillance spacecraft in orbit. Once again, the context is not Republic of Mars vs Tyranny of Earth, but Earth superpowers and coalitions of lesser powers protecting their interests throughout the solar system.
Rick:
"The more general answer to this question is that I'm giving my preference (or bias), and reason for same. It might be useful background information to know that I was a fan of Firefly, but was never even tempted to try the (rebooted) Battlestar Galactica, even after reading positive commentary. I just wasn't up for USN carrier ops in SPAAACE, even if well done."
Nor I, after a while. But I could just not even begin to engage Wild West IN SPAAACE! a la Firefly. But in general, I find them both equally implausible, for reasons carefully laid out in Atomic ROckets, among other places.
Yet I find firgates, cruisers, and battleships plausible in a properly constructed operatic setting, and analogies to military aircraft types plausible for the plausible mid future.
"And I'll go ahead and say what I've been trying to avoid - why such a friggin aggressive tone?
YMMV, but shouldn't we seek heterodoxy and polyculture over orthodoxy and monoculture? I humbly apologize for being too aggressive in that respect. Mea culpa, mea culpa, me maxima culpa.
BTW, "young jedi", in its most canonical sense, means "I respect your capabilities and potential, but I think you have a lot to learn". It is a very, very long way from a sneer. And, speaking canonically, perhaps we should recall who didn't take that form of address in the way it was intended, and what became of him. Still, I apologize for using it, and won't again.
Tony:
Based on invalid assumptions. Even chilled IR sensors just aren't that sensitive.
What do you mean? He was using numbers from a telescope we have today. You've moved from stubborn to fanatic.
See above. You can monitor the sky cheaply, or you can monitor it constantly. Not both, AFAICT.
No. It depends on the optics available, and what drive you're looking for. With terawatt drives, you might have naked-eye visibility in cislunar space, which makes longer-range stuff child's play.
I was overly hasty in dismissing your argument on needing personnel in a crisis area, or at least within a few light-seconds.
Nobody has total legal sovereignty over Earth, yet several powers have surveillance spacecraft in orbit. Once again, the context is not Republic of Mars vs Tyranny of Earth, but Earth superpowers and coalitions of lesser powers protecting their interests throughout the solar system.
That's not the same. Mars doesn't have surveillance satellites in earth orbit, nor would they even if there was a power there.
One thing that sprang to mind on language was this. However, I have seen a couple of good sets of made-up measurements in the hands of aliens. One good example is in Timothy Zahn's Conqueror trilogy. The aliens used units like beats, hunbeats, thoustrides, and tentharcs. (Roughly seconds, minutes, miles, and months.) If you start with that for humans, though...
Firefly, which I recently became a fan of, did all the swearing in Chinese. It didn't seem terribly forced, though, as people would use Chinese for other things, too.
Byron:
"What do you mean? He was using numbers from a telescope we have today. You've moved from stubborn to fanatic."
LSST? A telescope we have plans for today. It's a large (8 meter class), expensive instrument that can cover the nighttime visible sky in three nights, leaving the other half of the sky unobserved. Luke makes the caveat that we could put it in orbit. Okay, let's put it out at L5 -- all 2-300 tons of it. In the plausible midfuture? For strategic surveillance? Really?
Or maybe we could go with some more reasonable assumptions, like several dozen reasonably sized telescopes, with chilled IR CCDs, pointed at targets of interest, plus surveillance satellite constellations at accessible points of interest.
I leave it up to the readers.
"No. It depends on the optics available, and what drive you're looking for. With terawatt drives, you might have naked-eye visibility in cislunar space, which makes longer-range stuff child's play."
Yes, it depends on optics and drive strength. But if you're talking about operatic torch drives, we're not talking about the plausible midfuture.
"That's not the same. Mars doesn't have surveillance satellites in earth orbit, nor would they even if there was a power there."
It's the plausible midfuture. There is no "Mars". Just Earth space powers at and around Mars.
Byron:
"However, I have seen a couple of good sets of made-up measurements in the hands of aliens."
Oh, fine, it's to be expected aliens will have their own measurements - but in order for us to talk to each other, either they need to have learned our language or we need to have learned their language. Probably both. They should be able to convert stuff into our Earth units. (It's always phrased "X of your Earth units". Always.) Unless, of course, humans are a minority and aliens are the ones calling all the shots, in which case we'll just have to adapt to their culture...
I'll reiterate my previous position, though: if it makes sense for the characters to be using an alternate measurement, then include a footnote on what it converts to.
"The aliens used units like beats, hunbeats, thoustrides, and tentharcs."
Did the aliens have ten fingers? Because I'd bet against most aliens out there using a decimal system.
Tony:
"Okay, let's put it out at L5 -- all 2-300 tons of it. In the plausible midfuture? For strategic surveillance? Really?"
The International Space Station is 187 tons.
And why are we going to a Lagrange point? Low orbit will do for the desired application, provided you don't need to complete a full sky scan more than once every several hours. (You don't.)
In a thin margins hard sf future, I would think that calling someone "waste mass" would be about the deadliest insult possible.
Tony:
If there's any need for strategic surveillance, putting 200-300 tons in orbit won't be a problem.
Using different measurements for aliens is supposed to lend flavor to your story; using different measurements for humans is supposed to convay how far in the future or how seperated that human culture is from ours...but only if you do it right. All too often, the writer will be too blatant with it, not make the terms logical, or fail to let the reader know why these new terms came about to make the reader comfortable with the terms. I think it may be how the writer feels how hard or how easy it is or how importaint it is to the story for him to include them or not. Just because the writer things it's a good idea, doesn't mean that the reader does.
Ferrell
Milo:
"The International Space Station is 187 tons."
Yeah, in LEO, taking years to assemble.
"And why are we going to a Lagrange point? Low orbit will do for the desired application, provided you don't need to complete a full sky scan more than once every several hours. (You don't.)"
We've already established that it will take a number of days, using the technology in question. Placing the instrument in a Lagrange point reduces to a minimum the tracking rate induced by orbital velocity, without having to place the instrument in its own solar orbit.
Byron:
"If there's any need for strategic surveillance, putting 200-300 tons in orbit won't be a problem."
200-300 tons times however many instruments it takes to achieve an acceptable scan rate. Remember, we're taking some number of days to cover the sky. If you want it to be hours, well... At some point one has to accept that theroy and practice aren't the same thing, especially where limited resources are involved.
"On one hand, you have ridiculous crap like making up new words for minutes and seconds and curses that's just silly (centons, yarens, frak),"
The original Battlestar Galactica retired the trophy: "Range 30 microns and closing!" (Another reason I was prejudiced against the reboot.)
When it come to foul language my only real grump is usages like 'all f*cked up,' which apparently can't be traced back beyond World War II, and probably won't survive more than a couple of centuries.
I counter that this will not lead people will not build battlecruisers when they're inappropiate to local requirements, at least, not past the first few years (particularly if a war breaks out). Rather, what people would do is build whatever ships are appropiate to local conditions, but just call them battlecruisers.
That seems entirely plausible! I was just ragging on the popularity of the term. Bear in mind that in real life, 'battlecruiser' was a journalistic coinage, though the RN and other navies quickly picked up on it.
On the whole 'everyone sees everything' issue, my feeling is that if the setting is the Solar System, and enough resources are being thrown into deep space conflict to have constellations of interplanetary warcraft, then the major players will be able to invest in major tracking facilities.
Note that the cost of the Keck telescopes ($140 M) and Gran Telescopio Canarias (130 M euros) is comparable to a single AEGIS installation (reportedly $150 M).
In an interstellar setting things get different - you may enter a system with zero previous information, and presumably civil craft and even lesser patrol units are not all carrying AEGIS equivalent scan suites.
Things are also different if hostilities break out for the first time in a previously tranquil setting, and everyone has to ramp up.
Really, the point of 'everyone sees everything' is to emphasize that stealth cannot be assumed, and can be difficult/impossible to achieve against a robustly equipped enemy.
Snafu and fubar are newish but yeah, dating the work. Human nature doesn't change. There will always be cocky racecar drivers and charioteers and they'll work hardnto create the right impression of charm and swagger. But the leather jacket as status symbol the racer uses will be replaced by something else for the charioteer serving the same purpose. The centurion might not have mirrored aviator shades and a smokey hat like the cop who pulled you over but I bet he can make that armor and glare just as intimidating.
Using different measurements for aliens is supposed to lend flavor to your story; using different measurements for humans is supposed to convay how far in the future or how seperated that human culture is from ours...but only if you do it right.
I prefer that done with cultural attitudes, morals, and hangups. If the author does it right, this far off human culture that seems so alien can feel so real.
Rick:
"That seems entirely plausible! I was just ragging on the popularity of the term. Bear in mind that in real life, 'battlecruiser' was a journalistic coinage, though the RN and other navies quickly picked up on it."
I think it's popular because its recognizable. Even when it described real ships, in real navies, it had no real meaning. British battlecruisers were just exercises in speed and firepower with minimal armor. German battlecruisers were balanced fast battleships. So were the Japanese battlecruisers, being in effect the ships that the British constructors really wanted to build, had the RN given them the chance. WWII German and US vessels that are sometimes described as battlecruisers -- the US ships actually being labeled that in the contemporary press -- would probably be best described as "cruiser destroyers" (in the same sense as destroyers starting out as "torpedo boat destroyers"). Even more recently, the Soviet/Russian Kirov class heavy missile cruisers are still often referred to in the Western press as "battlecruisers". I would say that one is being historically and technically accurate in naming something a "battlecruiser" as long as it is larger than the standard cruiser of its day, but smaller than anything that could be reasonably described as a battleship.
Now, what one calls a "cruiser" is an interesting question. I would suggest that most ships in most space navies would be cruisers, while the largest would be, perhaps, "flag" or "command" cruisers, because that's their major function.
"Space Cruiser" might come to mean any manned spacecraft capable of interplanetary travel. A "Combat Cruiser" could mean the military variant. I can see a difference in termnology between manned and unmanned spacecraft, even those that perform simular missions.
Ferrell
A good operatic or semi-operatic taxonomy might be something along the lines of:
patrol cruiser
escort cruiser
scout cruiser
stike (or "attack") cruiser
For the more modular plausible midfuture warship, I can't escape the fighter-bomber analogy. I know it will be called something else, but I think the operational procedures will be similar.
Tony:
"I would suggest that most ships in most space navies would be cruisers,"
Doesn't "cruiser" tend to imply "ship that spends most of its time away from the fleet", though? In space, I am sure the tactical advantage of large fleets is going to continue.
Getting back to surveillance, in a plausible midfuture with a fair number of spacecraft then there will be an infrastructure of surveillance instruments to track them. Think of legacy "mission controls" to "STC" systems developed to protect orbital infrastructure to "Spaceguard" systems looking for incoming asteroids and comets
In more operatic setting the ships themselves will have their own sensor suites (including honking laser mirrors which can double as high definition telescopes) and the "no stealth/no horizon" trope will work to the advantage of the most developed space civilization since all the sensor data can be sent to every deployed ship, colony, asteroid base etc. so everyone will have a reasonably accurate 3D view of space. Obviously the 3D view of what is happening in the Jovian system will be more current and accurate than the view of the Solar system, since there will be an 8 light hour delay going from "edge to edge". Unless you have some sort of warp drive or wormhole system in place, few units will be able to move significantly in that time period.
Even when it described real ships, in real navies, it had no real meaning.
Note the entertaining flip side of this - the USN was at great pains to insist that the Alaska class were NOT battlecruisers. Absolutely not. Nothing to see here, folks. Move along, move along.
Milo:
"Doesn't "cruiser" tend to imply "ship that spends most of its time away from the fleet", though? In space, I am sure the tactical advantage of large fleets is going to continue."
For a couple of hundred years, cruiser was an independent operator. But with protected, and then armored cruisers, they became fleet units. (And before the advent of dreadnoughts, battle line units.) Throughout the last 125 or so years, "cruiser" has really just meant flexible, mid-sized, multi-role ship.
Rick:
"Note the entertaining flip side of this - the USN was at great pains to insist that the Alaska class were NOT battlecruisers. Absolutely not. Nothing to see here, folks. Move along, move along."
Not that it did them a bit of good with the press or with subsequent analysts, but the USN had a point. The Alaska class had (very large) cruiser hulls, and 12" guns were hardly dreadnought armament by 1940.
But it wasn't just the US that had PR problems with supercruisers. The Germans didn't like it at all that their's were called "pocket battleships". It caused more (fully justified) questions about treaty restrictions than they really wanted to answer.
This does give the SF author a ready made plot complication.
Lee Corey tried to do a work around in his book "Manna".
Since part f the premise was that new powers based on new groups would be the ones to pick up the different niches in new environments and exploit them, many of the ship types had names adapted from past and current sailing craft from the Indian ocean. The "skalavan" space fighter and the cosmo lorcha are two examples of his work.
Interceptors, escorts, orbital monitors both command(manned) and drone (unmanned); Carriers (AKA drone support vessels), manned Mobile Bases supporting drones and manned combat craft, and 'mission' ships that can be cofigured for either logistics or combat roles would seem to be the combat spacecraft types we would see in the PMF.
The only other military spacecraft I can think of would be those that fill the surface-to-orbit/orbit-to-surface role.
Ferrell
I'm not seeing escorts in the PMF. Commerce voyages wouldn't be inserted into transfer orbits where enemy ships could attack them, and peri-departure/arrival security would be provided by forces in the origin/destination orbitals. Likewise, I think interceptor would just be a particular configuration of mission ship.
For some crazy reason I'm finding early modern galley warfare to be a better and better analogy for space warfare with each passing day. With a lot of potential missions, but a single medium, it makes sense that there would be an optimum size main fleet vessel, plus smaller scout/patrol vessels, plus a few command vessels.
Tony:
I would say that one is being historically and technically accurate in naming something a "battlecruiser" as long as it is larger than the standard cruiser of its day, but smaller than anything that could be reasonably described as a battleship.
Battlecruiser is an incredibly ill-defined word. The "classic" battlecruiser was Fischer's, the dreadnaught with less armor and more speed. The Germans built ships with less guns and more speed. (Incidentally, Gneisenau and Scharnhorst are very similar to the WWI German battlecruisers.)
Both of the above types were the same size as their contemporary battleships. That pattern held throughout the life of the concept of the battlecruiser. Hood was the largest warship in the interwar period. The Kongos were reclassified as battleships after modification.
The modern conception of a battlecruiser as a small battleship is rather recent. I'm not entirely sure where it came from. The Alaskas weren't battleships under normal classification. I can see the definition changing in the future, though.
The problem with using the term "fighter-bomber" is that it brings an enormous amount of baggage with it. I understand what you're trying to get at, but the analogy is hindered by the aircraft baggage brought along.
My general opinion on warship terminology in space is simple: pick a system and stick with it. Don't worry about it beyond that. It is possible that, with modular systems, size will become more important than role. Of course, size is also a fluid concept with modularity.
Escorts might have their uses, though I expect them to be more of a deterrent than a serious force. If my enemy has an unescorted ship that I could intercept with a ship with a popgun, I would. If the ship carries a drone or two, I might have to think twice. I can't afford to send a ship capable of overwhelming the drones.
On farther reflection, two thoughts:
1. Battlecruisers
I think that the idea of a battlecruiser as halfway between a battleship and a cruiser dates to the Alaska class, as that's pretty much what they were.
2. Escorts
There are fundamentally two things an enemy can do to merchant shipping: capture and destroy. Capture is somewhat unlikely, given orbital mechanics. Destroy is much more plausible, using IPBMs. Convoys would be escorted primairly by ships that are antimissile focused. Or maybe antimissile modules would be mounted on some cargo ships.
The more I think about it, the more I become convinced that manned warcraft, and even manned fighters, will have their day. That day will be brief, but it will happen.
The period I refer to is the first war in any given sphere, excepting Earth. I use the term sphere to mean any area that involves multiple powers. I'll use an earlier example. Europa and Callisto are in conflict over access to the output of the Rare Earth mine of Metis. Callisto mounts a laser on a freighter and forcibly inspects Europa's freighters. Europa responds by putting a missile rack, a chemfuel rocket, and a hab module in a cargo module, and carrying it with their freighters. Some freighters are also modified. All are manned.
Why? Simple. Setting up a secure laser comm setup isn't impossible, or even that difficult, but it does take time. I'll make a SWAG, and say 6 months minimum with a lot of money. I doubt that a space colony will have the money to afford it while fighting a war. With more time, the cost drops dramatically.
This would be brief, just like many eras we romanticize, but I think it would happen.
Re: Byron
There never was a "classic" battlecruiser. The original concept, "HMS Unapproachable", was a super armored cruiser with a mixed battery of what were (in 1904) standard British armored cruiser weapons -- just a lot of them. Likewise, the propulsion was an exercise in no-kill-like-overkill. This all came at the expense of armor, but Fisher didn't expect the Unapproachable to hve to fight anything it couldn't outshoot. Given the contemporary line of battle tactics, that was probably right. Even if the Unapproachables got put in the line, they would be at the tail end of a line of battleships that, being British, would almost certainly outnumber the enemy's. So they would face off against (inferior) armored cruisers.
By the time the British battlecruiser was actually completed, concerns about enemy armament had led to the fitting of battleship armament. Once started down that road, these ships were destined to eventually face enemies with similar guns that could keep up and shoot it out. The Germans thought this all the way through and made their large cruisers much more ballanced ships. In any case, there just wasn't a "classic", just a series of revisions and expedients.
I'm not sure what similarities you see between the Scharnhorst class and the German battlecruisers. They were less of everything -- armor, firepower, and speed. If you mean their design ballance was carried forward into German battlecruisers, while British battlecruisers were unballanced, well, that's a point, but it could be made by just comparing battlecruisers.
BTW, when I said "fighter-bomber", I wasn't suggesting a designation for use in print, just a basis for thought about design and equipment in a modular environment.
Tony:
There never was a "classic" battlecruiser.
Yes. Different people used the word to mean different things. However, the closest we have are the British ones of WWI.
BTW, when I said "fighter-bomber", I wasn't suggesting a designation for use in print, just a basis for thought about design and equipment in a modular environment.
I do get that. However, that term comes with a lot of baggage. It suggests aircraft, which aren't a better model for spacecraft than naval vessels are. I'm also not sure about really modular warships. Laserstars or lasernoughts (ships with a few large lasers) will almost certainly be built from the keel up. Bolt-on doesn't work well with high-precision insturments.
Byron:
"Yes. Different people used the word to mean different things. However, the closest we have are the British ones of WWI."
Ennnnh...too simplistic for me. Pointing to the British battlecruisers as typical -- which is what most people take "classical" to mean -- just doesn't explain the history of the type well at all.
"I do get that. However, that term comes with a lot of baggage. It suggests aircraft, which aren't a better model for spacecraft than naval vessels are."
Well...there are both technical and historical reasons why they're called aerospace engineers.
"I'm also not sure about really modular warships. Laserstars or lasernoughts (ships with a few large lasers) will almost certainly be built from the keel up. Bolt-on doesn't work well with high-precision insturments."
A couple of things...
I don't believe in lasertars to begin with, for reasons already discussed at great length.
Even if one felt the need for integral weapon systems, that doesn't preclude the addition of mission modules or hanging various bombs and missiles on the outside. Look at the A-10 -- an aircraft built around the requirements of a gun, that's also capable of carrying bombs, missiles, and sensor pods.
Tony:
Well...there are both technical and historical reasons why they're called aerospace engineers.
I understand. I plan to become one. That doesn't change the fact that suggesting fighter-bombers is likely to lead to space fighters and all the attendent stuff.
I don't believe in lasertars to begin with, for reasons already discussed at great length.
Even if one felt the need for integral weapon systems, that doesn't preclude the addition of mission modules or hanging various bombs and missiles on the outside. Look at the A-10 -- an aircraft built around the requirements of a gun, that's also capable of carrying bombs, missiles, and sensor pods.
I think we're arguing past each other now. The A-10 is a lot closer to what I was thinking, thought I wouldn't classify it as a fighter-bomber, though.
The best analogy that I can think of for modular lasers would be a WWII 5-inch gun. It could be mounted on just about any ship, and it was a good AA (anti-kinetic), but it lacked killing power against surface ships. Most of those were sunk by more powerful weapons that had to be designed in.
I expect lasers to work in a similar fashion. The ship-killers have to be built in, but modular ones take over most of the kinetic defense.
As to not believing in laserstars, do you seriously take that to the point where modular lasers are as good as built-in ones? That's why I included lasernoughts.
Byron:
"I understand. I plan to become one. That doesn't change the fact that suggesting fighter-bombers is likely to lead to space fighters and all the attendent stuff."
Y'know...sometimes I get frustrated with people online, but I never expect somebody I'm having a conceptual discussion with to be that dense.
"I think we're arguing past each other now. The A-10 is a lot closer to what I was thinking, thought I wouldn't classify it as a fighter-bomber, though."
Close enough. Like I said, I expect people to be at least flexible enough to make reasonable generalizations.
"The best analogy that I can think of for modular lasers would be a WWII 5-inch gun. It could be mounted on just about any ship, and it was a good AA (anti-kinetic), but it lacked killing power against surface ships. Most of those were sunk by more powerful weapons that had to be designed in.
I expect lasers to work in a similar fashion. The ship-killers have to be built in, but modular ones take over most of the kinetic defense."
The 5"/38 was absolutely capable of causing a mission kill on destroyer sized ships. With enough ammo expended, it could probably cause one to sink.
In any case, AFAIK the vast amjority of surface ships sunk by other surface ships were victims of torpedoes, not big guns. And torpedo mounts were, if anything more modular than 5" gun mounts. Guns had to have magazine and handling room space set aside withing the ship. Torpedo mounts could just be bolted on deck and hooked up to ship's service power.
"As to not believing in laserstars, do you seriously take that to the point where modular lasers are as good as built-in ones? That's why I included lasernoughts."
I'm agnostic. The technology is too far in the future to make rational judgments.
Tony:
What do you mean dense? The use of the term fighter-bomber carries a suggestion of aircraft, and thus space fighters. That's what I'm saying. I know you don't mean that, but the implication is there.
The 5"/38 was absolutely capable of causing a mission kill on destroyer sized ships. With enough ammo expended, it could probably cause one to sink.
Yes. But that would take a lot of ammo, and was probably pretty rare. Larger guns were much better at that.
Torpedoes work, too. That would be kinetics.
And we've reached 800 posts. 20 more to the record.
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