Thursday, April 7, 2011

Space Warfare XIV: Things As They Ought To Be


At 100 kilometers per second, any object - be it a depleted-uranium slug, a carton of skim milk, or a throw pillow - packs kinetic energy equal to 5 gigajoules per kg, equivalent to 1195 kg of TNT, rather more than a ton of bang. In space the bang will be soundless, but it will still hurt.

(Someone in the back raises their hand to ask, '100 km/s relative to what?' For purpose of this discussion the answer is 'relative to whatever it hits.' And you should have figured that out on your own.)

This is the basis for kinetic weapons in space warfare. To regular readers of this blog it is no news; in particular I discussed kinetics in two segments of this series of posts. (Though the specific form of killer bus I described in the second post is a bad idea.)

I bring kinetics up again because they were long my weapon of preference for space warfare, for at least three distinct reasons, distinct in addressing different aspects of the overall problem:

1 - Missiles in space have effectively unlimited range, more than even Ravening Beams of Death.

2 - If you have the space technology to put large numbers of people in space, you pretty definitionally have the capability to throw lots of luggage, and throw it fast.

3 - There is reasonable scope for tactical maneuver in kinetics-dominant space combat, something that (it seems to me) is much harder to get in laser combat.

You may note that these three justifications are ranked by increasing meta-ness. The first is a general consequence of space speeds. The second hints at future history.

Any spacefaring society on a grand enough scale to have grand space battles has put generations or centuries of major effort into its overall space technology, whether its past has been peaceful or warlike. Long range lasers probably have more limited and mainly military applications. (Extensive use of laser propulsion does change this equation.) As a point of comparison, in the 19th century military technology tended to adopt new civil technologies, rather than being a primary driving force in itself.

The third point is most shamelessly meta. The people who fight wars are not concerned to make them interesting; that is only of concern to people inventing them in order to write about them.


Thus my picture of kinetic space warfare was kinetic in style as well as in weaponry. My starting point was the observation that if two ships are armed with similar-performance missiles, the more maneuverable ship has a crucial advantage. It can (at least in principle) maneuver to evade an enemy's missile, while the more sluggish enemy ship cannot quite evade its own missile.

Multi-ship tactics also look potentially complex - and therefore interesting. Ships maneuver like (3-D, vector) polo ponies to line up shots at opponents while avoiding the enemy's shots. The worst position a ship can be in is dynamically surrounded, so that a burn that carries it away from one enemy's missile envelope takes it right into another's.

The second worst position a ship can be in is to make a burn that accidentally carries it out of the fight at the point of decision, allowing the enemy to defeat its consorts in detail.

Lasers, in my vision, were purely secondary and defensive, intended for last ditch defense against incomings. There was a serious question in my mind whether a defensive laser armament was even worth carrying - the extra mass of a laser battery would mean reduced missile firepower, more sluggish performance, or both.

In this thumbnail description it sounds much like space fighters dogfighting, though the scale of the thing was such that battles would unfold over hours or days, even weeks.


I have not put any numbers to all this, except for the ones I gave at the very beginning, implying combat encounter speeds on order of 100 km/s. When I first came up with this image of space battles my assumptions were EXTREMELY operatic, as in photon drives with multi-g accelerations. Eventually I worked my way down to mere fusion torches in the low terawatt range.

A variety of holes, of various gauge, can be punched or burned through this vision of space combat, but it still represents one variation on the theme of what we all want for story purposes, Cool Space Battles.


I eventually abandoned this conception. Not because the propulsion was still operatic even in its later, more modest forms - any setting where you have space battles at all, other than near-Earth encounters in a primarily terrestrial war, is at least demi-operatic. But I came to suspect that the laser assumptions I was making were conservative out of all proportion to the propulsion assumption, yielding the equivalent of ships with gas turbine engines and smoothbore muzzle loaders.

By no means is that certain to be the case. Lasers and space propulsion are not inherently linked technologies (though under some assumptions they would be). And there is plenty of experience to show that battle performance of weapons often falls short of bench test performance, sometimes dramatically so. But I came to feel that it was special pleading to assume as much, and ended up with laserstars, as I have described them in prior installments of this series.

At some future point I might change my mind again.


Discuss. (Gentlemen, you can't fight in here! This is the War Room!)



The somewhat retro image is from Atomic Rockets - read also the discussion on the linked page.

418 comments:

«Oldest   ‹Older   201 – 400 of 418   Newer›   Newest»
Thucydides said...

This thread didn't just drift, it swam away.

Zombies? In Spaaaaaaace!

Bwahahahahahaha!

jollyreaper said...

Well, there's the problem of new ideas not being accepted until the last generation dies off. Immortality would likely mean slower societal changes. Maybe a trend of youngsters going off to prove ideas and the oldsters adopting them when the superiority is clear? Prevalence of archaic menonites who aren't just keeping up old traditions but are the people who were alive when that stuff was new?

I'd like to think that war is the domain of the young. It never gets to be society-ending because the true losses mount early on. Would presuppose longer life leads to compassion but that's not true with humans. Many oldsters are as ignorant as the day the dropped from their mamas having learned nothing in between.

I do think there would be fascinating perspective from early elders who have seen all of history.

There's a movie that needs to be seen, the Man From Earth. Explores these ideas.

Scott said...

you'll have to accept either one BBOD surviving out of 60
Ok. Sounds about right for the modern naval battlefield. 1200Kg of kinetics per target ship? I can put that into the mass budget, since I am assuming 4-5kiloton ships... And for further irony, 1200kg is about the mass of modern heavyweight torpedoes and cruise missiles. Or was that 1200kg of warhead, not counting bus?

That alone is a departure from combat conditions with milspec instruments run by military operators. (Who are as good as they can be, but who aren't elite instrument builders and maintainers. )

Ok, Now I'm offended. Generally speaking, the military techs I have known are better than their civilian counterparts, especially as maintainers. But I'll play the game. Let's assume that a military laser is 3 orders of magnitude less pointable/accurate than Hubble (and remember that hubble was state of the art 40 years ago). Hubble's designed focal accuracy is .1 arcsecond, so we're talking about a laser beam hitting somewhere within 100 arcseconds of point of aim. That's dead-target accuracy at 100km. Not great, but dumping 25 MJ per pulse into a target will do something ugly, even with a 10kps closing rate. IF (and I will admit it to be a rather large if, but it's certainly not impossible) a military laser has Hubble accuracy, then it will be able to fry that .5m diameter target at 100,000km. I think that's outside the effective range of the laser, though.

Tony, I'm just not seeing what experience you are drawing from to make the assumptions that lasers are somehow different from an astronomical telescope with a big honking flashlight at the eyepiece! We know what the 1980s state of the art was for spacebased telescopes: Hubble. That includes a mirror-heater system, by the way. We also know that modern telescopes are more than an order of magnitude more precise than Hubble. As the laser techs will tell you, optics are optics!

And if you're going to complain about vibrations again, a C130 has an internal acoustic environment of about 145db (yes, really), plus a high-amplitude 68hz vibration from the props, plus atmospheric turbulence. Helicopters are even worse, and they still use laser-target-designators to mark a target roughly 1m^2 at ranges in the thousands of meters. A nice, smooth, *known* environment for your lasers would be a laser tech's dream for accuracy.

=====
Now answer the social implications of a spoiled brat being lavished attention by twenty adults...

Good lord, it's an entire society of 'Paris Hilton's. Nuke it from orbit, it's the only way to be sure!

Excellent! So I take it we have agreement on throwing eggs at the writers of Galactica? Lol

Can I throw something more energetic instead? [evil grin]

Raymond said...

Mmm, zombies. Yum.

The zombie version I'm waiting for a thorough treatment of is still of the "virus" variety - but one that attacks and/or disables the prefrontal cortex only. Same lack of personality, emotion, conscience, and social inhibitors - but opening a door (or operating a firearm) isn't too great a task. Add potential for endemic infection and/or overriding behaviors from the parasite to suit your taste in paranoia and/or apocalypse.

The closest I've seen to this was the endgame of Dollhouse, or perhaps The Puppet Masters (from the other direction). Maybe, just maybe the Flood from Halo.

I think it was vaguely hinted at with the "rage virus"-type zombies, but those versions still lacked the higher brain functions necessary to make a believable apocalypse (I'm with Milo on that one, no matter how much I adore World War Z).

jollyreaper:

"...but these people are not going to go from infected to ravening in five seconds."

Necrotizing fasciitis can eat flesh 3-5 cm per hour. There are neurotoxins which work so quickly you can't process the pain from the bite/sting/pick-your-delivery-method. Depending on how you set up the biology, it may not be possible for five-second infection times, but a few minutes could be plausible.

Raymond said...

Scott:

1200 kg of warhead (well, multiple warheads), not counting bus. To get a 5 km/s delta-v, you're probably looking at ICBM-class missiles. (Rough guess, of course.)

WRT Galactica:

The shining pinnacle of that show was the first half of the third season, with the occupation and escape from New Caprica. Freefall from there, and a hard stop at the end. Could have probably ended it halfway through the fourth, when they get to the rubble called Earth, and gone out on a successful gutpunch. (Yes, as previously mentioned somewhere, after 2000 years it wouldn't be entirely uninhabitable. Still would've sucked.)

Nick P. said...

Raymond:

I think the movie you are looking for is 'The Crazies'.

Milo said...

Jollyreaper:

"Well, there's the problem of new ideas not being accepted until the last generation dies off."

Wouldn't they, though? It's true that people can have a degree of resistance to ideas developed late in their life (or "decades into their life", which isn't the same thing if you're immortal), but people can and do change their minds and adapt to new technologies, too.

Fashions change every few years, or so I heard, since I'm not particularly following them - but in any case far more rapidly than once a generation. Of course, fashion is just superficial aesthetics, which is easier to accept change in than important cultural values. I see elves trying out new technologies and traditions in the same way they try out new fashions.

If a scientist is in it for the thrill of discovery, then will he ever tire of pushing the cutting edge forwards? (Well, if he does, then hey - there you have your attitude change!)


"Maybe a trend of youngsters going off to prove ideas and the oldsters adopting them when the superiority is clear?"

Hmm. That's a definite possibility. (Particularly for technologies where the testing is dangerous, like space travel. But there's no reason oldsters couldn't still build the rocket, although they'd be queasy about piloting it.) But you still need to have real work for the oldsters to contribute, too. They can't just sit and loaf around after hitting 65.


"Prevalence of archaic menonites who aren't just keeping up old traditions but are the people who were alive when that stuff was new?"

Nice. But just how would people approach religions when they still remember when they were founded? Imagine if you could just ask someone who lived in Rome two thousand years ago if Jesus was real. Imagine if Jesus himself - or, oh, Muhammed, since Jesus was supposed to be not-really-human anyway, and also got himself crucified - were still around and still preaching his faith.

We tend to think of religions (even relatively new ones) as ancient things, wisdom handed down through the ages, with origins shrouded in the mists of time (giving a convincing illusion that they've been around forever). But elves might not see it that way.


"I do think there would be fascinating perspective from early elders who have seen all of history."

Oh, definitely.

Raymond said...

Nick:

Haven't seen either version. Any good?

KraKon said...

"The zombie version I'm waiting for a thorough treatment of is still of the "virus" variety - but one that attacks and/or disables the prefrontal cortex only. Same lack of personality, emotion, conscience, and social inhibitors - but opening a door (or operating a firearm) isn't too great a task. Add potential for endemic infection and/or overriding behaviors from the parasite to suit your taste in paranoia and/or apocalypse."

Are you telling me that your favourite zombies are essentially people sleepwalking...with their eyes open. Except there's less delirium and more whining for brains....
I think the fact that a brain-zapped zombie can open a door or shoot a gun is entirely possible...those actions lie in the domain on muscle memory and the zombie wouldn't lose them in undeath.
On fantasy zombies-why content yourself with neighbouring turned-into-zombies-slaves when you can set up schools next to (or in) the necromancy conversion camps. We're being educted for a better service in the afterlife! Classrooms will be grim though.

"1200 kg of warhead (well, multiple warheads), not counting bus. To get a 5 km/s delta-v, you're probably looking at ICBM-class missiles. (Rough guess, of course.)"

5km/s is an ideal velocity for chemical rockets. The mass ratio is very near one, meaning a 1200kg warhead would need 1200kg propellant, plus the remass to compensate for structure and drive mass.
Please note that 1/60 survival rate was only from going though the laser defense. A second layer of kinetic interceptors, or the need for more than one BBOD per 2.5ton bus to hit the target would vastly increase how much how have to carry onto the battlefield.
Also, this is a sliding scale. Increase velocity, reduce mirror size, increase laser power, decrease beam wavelength, change armor material, increase spin rate...all are factors that change the survival rate in a mostly proportional way.
For example, the 2.5ton bus can be either useless (only one in 600 BBODs go through at 1.1m/s revolution) or extremely effective (a single bus can ensure a kill if the BBODs revolve at 110m/s).

KraKon said...

On accuracy:
Why has no-one thought of removing the laser and its mirror from the ship?
In the case of an axial laser mount, with the lens between the target and the laser generator, we could unlatch the laser generator, the lens and the shutter/targeting system as needed. The generator would still be fed electricity through the flexible attachments. The ship now protects the laser from impacts and all such stuff, powers it, and asorbs all the laser's vibrational energy during firing; rubber mounts are not enough, like those on submarines, because if you hit the submarine's hull with a big artillery shell, internal machinery sure will feel it. They'll be pulled along with the external hull, albeit with the acceleration smoothened out.
Here, all the ship has to do is maintain its position around the laser generator. The maneouvering thrusters cancel out momentum transfer from armor vaporizing/kinetic impacts and the such, and finally remove the total noise energy in it.
This is like the pundulum concept I described earlier, except the weight is now the ship, and it surrounds the weapon rather than being an internal mechanism.

PS: Ever hear of Mongols shooting when all four hooves of their horses are in the air? This system tries to achieve that, with waves of disturbing vibrations going back and forth between the laser mount and the ship, the laser only shooting between the smooth transition periods. Even if the vibrational waves are at 60GHz, they can be smoothened out into waves who's period has lulls long enough for you to target and shoot. Modern day example: the Jaguar E-type has a powerful engine with many thousands of explosions happening inside of it per second. Put a cut of water on the fine machine and the surface won't even ripple.

jollyreaper said...


I think it was vaguely hinted at with the "rage virus"-type zombies, but those versions still lacked the higher brain functions necessary to make a believable apocalypse (I'm with Milo on that one, no matter how much I adore World War Z).


I could see someone developing this for use as a terror weapon. The only question I have is how the chain of infection would play out.

I wonder if anyone's done mathematical models for how zombie plagues would work. If it was only bite infection I just don't see it working out all that well. Certainly the people first encountering it wouldn't know what they're dealing with and won't recognize a bite as a death sentence. But after a certain point in time people would know how to recognize the infected and deal with them. That's why I think you'd need "everyone who dies comes back" to make a dumb zombie apocalypse happen. And there's going to be a critical threshold where people refuse to go to their jobs, society breaks down, and organized human resistance fails. If not for that then the zombies could be quelled. Watch that Sarah Jane movie, it's a good one.

The traditional moat of zombies from the movies is what makes them so hard to deal with shortly after the apocalypse. That would be over and done after a few years.

As for rage-style zombies, I could see that developed as a terror weapon. A targeted virus that causes specific brain damage that leaves a human with higher cognitive function but violently insane. There was a comic called Black Gas that went that route, not with a virus but with a volcanic gas on an island that did the same thing. There was the aforementioned Crazies movie and the remake. Stephen King's Cell went with live zombies, a signal sent via the cell phones would cause the brain to short-circuit and go crazy.

The danger with a crazy-making virus is that something like this could boomerang around and get you. I think you'd have to be on the lines of insane religious terrorists to try and use a weapon like this. Now if you add in restriction of blood flow to the extremities, you could get leprosy-type symptoms that could make victims look wretched and like walking corpses even though they're still alive. Preserved higher cognitive functions will still see them feeding themselves, taking water, and trying to maximize chances of survival. The real question is if you could plausibly make the crazies not attack each other. Because otherwise you'd see infections burn themselves out in short order.

There's a book I haven't read called Dog's Blood which is about the emergence of Rage-type behavior in society. It's not causing zombie apocalypse collapse but it's more like society-under-siege from Clockwork Orange, never knowing when someone in the crowd will go berserk with a willy sculpture. Don't know if it's any good.

Tony said...

KraKon:

"Modern day example: the Jaguar E-type has a powerful engine with many thousands of explosions happening inside of it per second. Put a cut of water on the fine machine and the surface won't even ripple."

That's because the Jag has a very cleverly designed engine, integrated into a very cleverly designed chasis, all working together to transfer mechanical noise into the surrounding medium (ground and air). The same is true of modern submarined noise control.

A spacecraft in space has no surrounding medium. It can only convert mechanical noise into heat and radiate it. That's the biggest problem I see -- while the noise is circulating around the spacecraft structure, it's screwing up the sight picture. Even with active damepening you're just evening out the bumps into a constant jitter. You can't magically disappear the noise energy. Observing and shooting at equilibrium points in the cycle is an interesting suggestion, but I wonder if you could smooth out the noise that predictably.

Byron said...

Tony:
That would be a reason to get rid of the crew. They're going to be the source of most unpredicatble noise. And we have equations for jitter. I'll give an example:
A 6.5 meter mirror (James Webb) with a 500 nm laser, beam quality 1.5, jitter 100 nr. Beam diameter at target 1,000,000 km away? 0.172673033 meters.
(The equation used should be near the bottom of laser weapons.)
Without jitter, diameter is 0.140769231 meters. I think this should clear things up some. You'll probably demand a couple orders of magnitude more jitter, but even then, the beam isn't that big.

jollyreaper said...

but people can and do change their minds and adapt to new technologies, too.

I'm thinking of people who might object to something on philosophical grounds or reject the new science. Someone who made his career building the geocentric model of the universe might never cotton to the heliocentric view, even when the evidence proves contrary. A seminal figure in phrenology might be shamed and humiliated when his life's work has been debunked. Since he and his friends won't be dying off, the battle might rage for a long time. Consider that you still have chiropractors who discount the germ theory of disease. There were geologists even into the 1950's discounting plate tectonics. Now if the new idea is good enough, people with less skin in the game might feel comfortable using the newer, more correct ideas but the rancor will last longer.

Of course, fashion is just superficial aesthetics, which is easier to accept change in than important cultural values.


Exactly. People don't tend to have as much invested in fashion as they would in a religion or a theory that's their life's work. Few scientists want to spend their entire life proving something doesn't exist, they usually want to prove something does exist. Even though proving the nothing is supposed to be as rewarding because it's still expanding our knowledge.

I see elves trying out new technologies and traditions in the same way they try out new fashions.

I see some elves doing that. I see others holing themselves up in their archaic societies and letting all the rest of this stuff pass them by.


Hmm. That's a definite possibility. (Particularly for technologies where the testing is dangerous, like space travel. But there's no reason oldsters couldn't still build the rocket, although they'd be queasy about piloting it.)


I'm thinking it's more along the lines of "Bah, flying machines will never work" and so the youngsters go off to work on it themselves and finally come back to the main society when they have proper passenger liners. Or maybe compare to computers. You might see the oldsters rejecting the tech for decades until finally it becomes so compelling they can't continue to say no. But you could also see stuff that's broadly available in small, high-tech polities that never manages to make the bridge to the larger, oldster polities. Sort of like how progressive menonites are fine with having phones at the business but will not have them at home. Some menonites reject any tech they can't make themselves out of desire for self-sufficiency, others don't like the negative social impact and will use the tech only in a controlled fashion.

real. Imagine if Jesus himself - or, oh, Muhammed, since Jesus was supposed to be not-really-human anyway, and also got himself crucified - were still around and still preaching his faith.

Go watch The Man From Earth. :)

Byron said...

Sorry, made a math error. Range is 1,000,000 meters, not kilometers. I thought those numbers were strange.

Tony said...

Byron:

"That would be a reason to get rid of the crew."

Not if the crew is there to make sure you have any kind of weapon at all ready for combat when the shooting starts. Don't cut off your nose to spite your face.

"You'll probably demand a couple orders of magnitude more jitter, but even then, the beam isn't that big."

Sigh...

Beam diameter is the last thing a laserist should be worried about. The thing that I'm skeptical of is beam pointing accuracy at what people keep claiming to be effective ranges.

jollyreaper said...

Oh, about immortality, got me thinking about the Cenozoic Park idea. I figured out how that story would go.

Husband and wife researchers are working on mind uploads. The Big Societal Collapse happens, human extinction on the way. They're on a station and are able to persist for a few decades before death. They get the tech working and upload at the end of their lives as a hedge against oblivion. They don't think it will work.

Wife wakes up in the AI world 50k years later. She's met by a humanoid avatar representing one of the AI's. She's told that her upload research was discovered and they've now been able to perfect a cloned body for her to live in. They are trying to work on recovering husband but she is the first pre-extinction human mind they've found. They want her opinion on how well they've done recreating humanity. Genetically they know they have it right but they're curious about how the societies compare.

The story will be one of increasing revelation as she understands just how big the effort is. She starts out seeing children raised by avatars. They're going into a fresh new society. But they're not the first. She is introduced to prims who have chosen to live at one with nature like pre-civilization humans. That's a lifestyle choice. Others have chosen progressively higher tech levels -- idealized Hobbitons, Bedford Falls. Each village represents another attempt at exploring the human experience, lived out by the humans themselves. There are failed villages preserved as warnings for others -- societies that could not live peacefully. But every one of those villages represent humans who have agreed to subordinate absolute sovereignty to the AI's. It's a philosophical distinction because they're certainly allowed to destroy themselves if they wish but they aren't allowed to cause real harm to the rest of the biosphere. But some even find that too restrictive. They are free to move offworld. The orbital polities are self-contained and any success or failure is borne completely by them. But there's still some limitation to the activities allowed in Earth orbit -- can't risk accidents impacting the biosphere, so some of the habitats are in the process of mounting ion engines to begin a great migration out to Jupiter space where they can finally get some elbow room.

Throughout this process there's a third answer our original human is wondering about. There's living as baseline humans as wards of the AI's. There's seeking offworld independence from the AI's. But what of becoming more than human and seeing what AI society has to offer?

As our original human has come to expect, the avatar she's talking to is not a pure-strain AI but her post-human self. Her backup was recovered 10k years ago and was the first of her to tour the human societies. The AI's did want to know what her reaction would be. And after she gave her opinion she suggested that it might be a good idea to restore another backup years down the line to see what her opinion would be then -- fresh, unbiased, genuine. And as she'd also come to suspect, her husband has been going through the same process with his own post-human self. Their only obligation complete, they are told that how they want to live the rest of their lives is up to them.

Tony said...

Re: Milo

WRT high velocity kinetic attacks...

Once again, as a campaign planner you have to make a distinction between the ship as an instrument of policy and the weapon/bus as an item of ammunition. You launch your busses close to midcourse turnover, when you're still moving relatively quickly. It may cost you a little extra fuel/remass to get a trajectory pointed at the target space from that far out, but it's not unreasonable.

The same goes for multiple attacks -- launch them at intervals while still at high interplanetary velocities. It takes still more fuel/remass, but that's a cost of doing business.

The ship continues to decelerate while the attacking systems follow a ballistic trajectory to the target area. The ship arrives some time after the kinetic attack and uses it's reserve weapons to clean up anything left in the target space. Or it doesn't do anything except accept the surrender of remaining forces and land some military police.

Tony said...

jollyreaper:

"Oh, about immortality, got me thinking about the Cenozoic Park idea. I figured out how that story would go."

I can't buy it. Despite old timey SAC propaganda, peace is not a human profession. It's just a temporary condition. The humans would rebel sooner or later, and probably sooner. Or your protagonist might find that 90% of the villages have been destroyed by the AIs for being "non-viable", which she eventually learns means rebellious. The surviving 10% she has nothing but contempt for, because they are occupied by people who are culturally (and perhaps genetically) predisposed to being slaves.

Byron said...

Tony:
Not if the crew is there to make sure you have any kind of weapon at all ready for combat when the shooting starts. Don't cut off your nose to spite your face.
And I can't make a solid-state laser that can be cold-stored for a couple of months?

Beam diameter is the last thing a laserist should be worried about. The thing that I'm skeptical of is beam pointing accuracy at what people keep claiming to be effective ranges.
And for about the 50th time, we have no good numbers. Hubble has accuracy that's better than it's resolution, so we have to take that as a lower limit, not an upper one. We haven't seen a case where better accuracy would be helpful, but wasn't achieveable. That would be an upper limit, and would give us data. I've looked for other stuff, but haven't found anything.
And all the noise and such you keep speaking about would be jitter. IIRC (and it's been a while) the ALL had jitter on the level of a microradian. That was designed 30 years ago, and on a 707, in an atmosphere, with a chemical laser. Order of magnitude increases shouldn't be too hard.

Tony said...

Byron:

"And I can't make a solid-state laser that can be cold-stored for a couple of months?"

It's not the laser, it's the entire integrated weapon system built around it. And the mission isn't two months -- it's however long it takes to get to the patrol station, how long the patrol lasts, and how long it takes to get back. Using Mars space as an example area of operations, that could be up to three years.

"And for about the 50th time, we have no good numbers..."

And for the umpteenth time, not having hard numbers means we don't know what the environment would be like. But we have enough reason to suspect it wouldn't be anywhere near as quiet as that required for scientific observation.

"And all the noise and such you keep speaking about would be jitter..."

And, for another time, the acoustic environment of even a noisy aircraft or sea vessel is not the isolated acoustic environment of a spacecraft. Every bump, thump, slap, and tickle has to be converted into heat somehow, and all any countering mechanism can do is smooth out the noise. The noise still has to be converted to heat and radiated.

Byron said...

Tony:
It's not the laser, it's the entire integrated weapon system built around it. And the mission isn't two months -- it's however long it takes to get to the patrol station, how long the patrol lasts, and how long it takes to get back. Using Mars space as an example area of operations, that could be up to three years.
OK. Poor word choice. Maybe I should have said "couple of years."
Either way, we aren't going to agree on this. We've already figured that out.

And for the umpteenth time, not having hard numbers means we don't know what the environment would be like. But we have enough reason to suspect it wouldn't be anywhere near as quiet as that required for scientific observation.
I can agree with this statement in principle. However, you claim that future combat optics can't match current scientific optics. That's what I have a problem with. While future combat optics will be worse then same-era combat optics, I don't think we can genralize like you do.
We have no hard numbers except for Hubble, and those aren't the most reliable. Even then, 34 nanoradians isn't bad. We might be restricted to .25 ls or so, but that's still far enough out to make low-speed kinetics useless.

Anonymous said...

Zombies; dear Lord, can you imagine the PSA's celibraties would make about those? And just think about how much more annoying those commercials charities make trying to guilt you out of money if they were made about zombies instead of underprivilaged children?
And besides diet, what is the difference between immortals humans and vampires?
5Kps for chemfuel missiles during a kinetics attack...wouldn't that be on top of your closing speed?

Ferrell

Tony said...

Byron:

"However, you claim that future combat optics can't match current scientific optics. That's what I have a problem with. While future combat optics will be worse then same-era combat optics, I don't think we can genralize like you do."

But it's by nature a general proposition -- either the capability will be there or it won't be. If it's there, it will be put into applkication quickly enough by all powers capable of fielding space forces in the first place (Just like tanks and aircraft became almost ubiquitous in modern armies over a relatively short period of time). If it's not there, then it won't be put into application by anybody.

So the question is whether the basic technical issues can be solved. I think it's a tall order for .1 lsec lasers. I don't think it's that tall an order for homing kinetics at 5-10 kps (we alread have them, as part of our NMD system) or lasers with 5000-10000 km effective ranges against ship sized targets and 500-1000 km effective ranges against kinetic munitions.

Byron said...

Tony:
The problem is that you seem to be freezing PMF at now + 20 years. I'd multipy your numbers for lasers by 5 as a start. Your kinetic numbers are reasonable, but you aren't going to get much more than that with chemfuel without staging, and that's not fun at all.

But it's by nature a general proposition -- either the capability will be there or it won't be. If it's there, it will be put into applkication quickly enough by all powers capable of fielding space forces in the first place (Just like tanks and aircraft became almost ubiquitous in modern armies over a relatively short period of time). If it's not there, then it won't be put into application by anybody.
Exactly. I'm not sure how you get from that to "it's impossible" without ignoring logic entirely.
If we have lasers with effective ranges of 30,000 km against ship-sized targets, slow kinetics go out the window. You'll be dead before they hit. And if the laser can hurt a ship at 30,000 km, then it can burn a projectile very quickly at 3,000. (It'll do 100 times as much damage, and increasing as range drops.)

Ferrell:
5Kps for chemfuel missiles during a kinetics attack...wouldn't that be on top of your closing speed?
Yes, but I don't expect that to be too high. It's easy to get an 'everybody dies' that way, which is no fun at all. Either 5 km/s is tactically significant, or why are you wasting mass on the booster?

Tony said...

Ferrell:

"Zombies; dear Lord, can you imagine the PSA's celibraties would make about those? And just think about how much more annoying those commercials charities make trying to guilt you out of money if they were made about zombies instead of underprivilaged children?"

"Friends don't let friends become Zombies."

"This is Fred. He was a happy, normal family man until he became a Zombie. Please sign and carry your donor card so we can help feed Fred non-canabalistic human flesh.

Also, for just $100 a month, you can help feed one of Fred's children, and keep him or her off the streets, where they might be zombified themselves.

Don't you want to help?

Won't you make a call to the United Zomby Relief Fund and register a pledge?

Servicemembers and federal government employees -- please remember UZRF (#2012 in your Agency Guide) when considering a Combined Federal Campaign contribution."


"And besides diet, what is the difference between immortals humans and vampires?"

At least vampires and other canabalistic undead have a motivation to keep the human race a going concern. Other immortals could take us or leave us (except maybe for a stable of the most sexually desirable humans, just for fun).

"5Kps for chemfuel missiles during a kinetics attack...wouldn't that be on top of your closing speed?"

Apparently common sense tactics need not apply.

jollyreaper said...

I can't buy it. Despite old timey SAC propaganda, peace is not a human profession. It's just a temporary condition. The humans would rebel sooner or later, and probably sooner. Or your protagonist might find that 90% of the villages have been destroyed by the AIs for being "non-viable", which she eventually learns means rebellious. The surviving 10% she has nothing but contempt for, because they are occupied by people who are culturally (and perhaps genetically) predisposed to being slaves.

It's a thought experiment. You can't really prove or disprove anything with that sort of thing, just make the best argument you can one way or another.

The AI's are deliberately futzing with the upbringing of people, or at least the seed members for new tribes. Second generation children are raised by the first and the AI's stay out of the way at that point. Our personalities are the product of nature and nurture -- how much of each comes to bear and whether or not it varies from person to person is all up for debate. They're trying to make sure they have the right genotype for baseline human and are loathe to tinker with it -- the variables they're deliberately playing with are all on the nurture side.

As I said, there are going to be failed villages. They fell apart in tribal warfare -- which the AI's would allow -- but didn't spread to continental warfare -- which the AI's say is bad for the environment.

Now as for the whole AI resentment thing, that's why I mentioned the humans moving offworld, heading out to Jupiter.

My personal feeling on the matter is that humans can be divided into people who'd like the AI nature reserve existence and others who would find that utterly intolerable. I think the former would be a larger group than the latter. Given that there's a ready-made safety valve in being able to go offworld, it should never have to escalate to war against the AI's, a war the humans couldn't even begin to properly contemplate fighting.

Now what would really bake the old noodle is if the idea of the Amish coming of age thing is observed, rumskellingsomethingorother. It's where the young are allowed to go out into the world, see what it's about, and if they return to the fold it is because they want to, not because they have to.

So imagine growing up in a primitive tribe and only knowing the eden existence. Your curiosity is piqued by the strange lights in the sky, the hinting at bigger and better things. You hear about the great machine spirits in the ground that the elders speak of with reverence. Your friends are content with the stories and live in the now. You are not satisfied. You want to learn more. And it's all open to you. You can learn about the gods, you can learn about the humans who serve them openly. You can journey to the stars.

Scott said...

That's because the Jag has a very cleverly designed engine, integrated into a very cleverly designed chasis, all working together to transfer mechanical noise into the surrounding medium (ground and air). The same is true of modern submarine noise control.

No, submarine noise control is all about emitting ZERO noise into the water, because emitted noise is how you find subs. Tom Clancy claims that the Ohio-class emits about 40W of acoustic energy into the water including the crew walking around. 4MW at 300K (ie, lifesection heat) with .95 emissivity radiators requires a minimum of 9200m^2. Assuming that you can use 4 radiators 90 degrees apart (to use both sides), and using a safety margin of 1.75, that's four 40x50m radiators, each massing 1000kg using carbon-carbon heatpipes.

Also, by designing to eliminate torque effects from your machinery, you are going to end up using designs that will also minimize sound generation because of the opposing sine waves.

Tony said...

Scott:

"No, submarine noise control is all about emitting ZERO noise into the water, because emitted noise is how you find subs. Tom Clancy claims that the Ohio-class emits about 40W of acoustic energy into the water including the crew walking around."

You can't emit zero noise into the water. And 40 watts over what duration? An hour? A minute? A second? I can't believe the first, because that's the energy draw of a weak lightbulb -- for a boat the size of a large WWII cruiser.

Byron said...

Tony:
What do you mean, 40 Watts over an hour? That's ramp-up. It's entirely possible with a lot of work. They have every incentive to keep it low. That's a decent bit of sound. 1 W/m2 is 120 decibles, which are logarithmic. Plus, I don't think it counts flow noises and such.
You've won a partial victory here, BTW. I've added jitter and pointing accuracy to my latest shipbuilder spreadsheet.

Tony said...

Re: jollyreaper

All of that is completely foreign to me. Most people I know prefer their personal peace and quiet, but very few would prefer to be led around by the nose. And those like that that I do know are remarkably weak and dispicable people. Maybe I'm observing a skewed sample, but I don't think by that much.

Also, running away to avoid conflict isn't exactly a common human trait, even when running is eminently possible. People seem to rather go down fighting for what they have, than to relocate, even if the relocation is relatively free and easy.

And I understand that it's a thought experiment. Just don't expect a lot of people to buy and read the book(s) that come out of it. it just doesn't align with what most people consider human nature. People just don't think peace is worth the cost of being a garden curiosity.

Tony said...

Byron:

"What do you mean, 40 Watts over an hour? That's ramp-up. It's entirely possible with a lot of work. They have every incentive to keep it low. That's a decent bit of sound. 1 W/m2 is 120 decibles, which are logarithmic. Plus, I don't think it counts flow noises and such."

I would agree with you that the discussion should be only about internally generated noise. An Ohio class submarine can be (very roughly) characterized as a cylinder 170 m long by 13 m in diameter. It works out that 40 watts of energy can be evenly distributed over that surface at a rate of .006 watts/m^2. When you do the math, that comes out to 98 decibels. Hmmm...about like the inside of a subway train, one online chart tells me. Louder than I thought. And believable.

But that represents the noise that the submarine puts out constantly, when all of the transients of higher amplitude are smoothed out. Imagine trying to aim a precision instrument at a target of less than one arcsecond in apparent diameter inside a subway train...

Scott said...

What do you mean, 40W over what duration? One watt is defined as one joule per second. So, 40 joules per second over a rough surface area of 6000m^2. How many db does that work out to, Byron?

Believe me, Ohios are as close to utterly silent as can be achieved with 1980s technology. When the sub glides past Hood Canal Bridge, all you hear is the slap of the waves against the hull. No other noises at all.

The Seawolf (1990s tech) and Virginia (2000s tech) classes are even quieter. It can be done, it just costs. Like $2 billion per ship, when a comparably-sized surface ship is $750m.

Tony said...

Byron:

"The problem is that you seem to be freezing PMF at now + 20 years. I'd multipy your numbers for lasers by 5 as a start. Your kinetic numbers are reasonable, but you aren't going to get much more than that with chemfuel without staging, and that's not fun at all."

I'm not freezing anything -- I'm just not convinced that there is much more precision to be found in mechanical systems. I think we're to the point of asymptotically increasing precision down to a practical physical limit, after having picked all of the low hanging fruit. And weapon systems have a lot of mechanical parts, even lasers.

"Exactly. I'm not sure how you get from that to "it's impossible" without ignoring logic entirely."

I'm not saying it's impossible -- just impractical when military service conditions are considered.

"If we have lasers with effective ranges of 30,000 km against ship-sized targets, slow kinetics go out the window. You'll be dead before they hit. And if the laser can hurt a ship at 30,000 km, then it can burn a projectile very quickly at 3,000. (It'll do 100 times as much damage, and increasing as range drops.)"

But I'm already on record as not accepting your premise -- lasers with 30000 km effective ranges. So I have to treat the above as a complex question for purposes of discussion.

But, to play in your ballpark for a moment, please remember that a laser is not subject to the inverse square law, because it is collimated. With a beam diameter of 10 cm at 30000 km and a beam diameter at the emitter of 5 cm, you need a divergence of 0.000001852 milliradians. Anybody care to do the math on the beam frequency for that number, assuming perfect collimation?

In any case, taking this assumption, you have a spot size of 5.5 cm at 3000 km, which means the energy density at 3000 km only about 3.3 times as much as at 30000 km.

Now, you will get 100 times as much accuracy for a target of a given diameter, which will certainly be helpfull. But remember, as far as I am concerned, all of the distances have to be 1/3 to 1/6 of the ones you propose.

Tony said...

Scott:

"What do you mean, 40W over what duration? One watt is defined as one joule per second. So, 40 joules per second over a rough surface area of 6000m^2. How many db does that work out to, Byron?"

I was thinking in terms of energy (as in kilowatt hours), not work. And you can see from one of my posts above that it works out to 98 decibels. Which is a lot louder than I would have thought, actually, but still believable.

WRT, what is currently achievable, or achievable in the plausible midfuture, please remember that you can only reduce waste heat in the form of noise so much, and still have a machine that does useful work. The more machines you have doing some kind of work, the more noise they make, even if each one makes the minimum amount possible. To draw this back to waht seems to be the major bone of contention, there is going to be a lot more going on inside a warship than there is inside a scientific instrument, and by definition infinitely more (proportionally) than there is going on inside a perfect emitter that has zero moving parts. So theoretical ranges based on theoretical emmiters or even laboratory instruments are simply not applicable to the discussion.

Byron said...

Tony:
But, to play in your ballpark for a moment, please remember that a laser is not subject to the inverse square law, because it is collimated.
Wrong. Well, not quite right. For a fixed-focus laser, you are correct. However, a variable-focus laser does effectively obey the inverse-square law, at least as it applies to maximum intensity.
Note: This is what I remember. It might be wrong in details or in toto. I defer to Luke on this.
Remember the spot-size formula:
RT = 0.61 * D * L / RL

where:

RT = beam radius at target (m)
D = distance from laser emitter to target (m)
L = wavelength of laser beam (m, see table below)
RL = radius of laser lens or reflector (m)

This is the minimum possible spot size for a given range, if the laser is focused at that range. If the laser is focused at a different range, the spot will be larger. The overall shape of the beam will be something like an hourglass, provided that the spot is smaller than the mirror.
Note that spot radius scales linearly with D, distance to target. Area will be proportional to the square of radius. Intensity or flux will be inversely proportional to area, which is proportional to the square of distance.

The example given is basically setting the focus for infinity. If focused on 3000 km, the spot size would be 1 cm.

I'm not going to argue exact ranges again.

Milo said...

Jollyreaper:

"I see some elves doing that. I see others holing themselves up in their archaic societies and letting all the rest of this stuff pass them by."

For how long, though?

Sure, maybe you're invested enough in the old ways that you'll take two hundred years to let people convince you to change your mind.

But two hundred years isn't that long...


"I'm thinking it's more along the lines of "Bah, flying machines will never work" and so the youngsters go off to work on it themselves and finally come back to the main society when they have proper passenger liners."

Yeah, but by the same token: Abbas ibn Firnas built a working glider in 875, and Leonardo da Vinci kept trying to develop flying machines. Imagine if instead of the Wright brothers, one of them was still around when things like aluminium and combustion engines were invented, and went "Hey, maybe I can use that! Let me dig up my old plans and see if I can get them to work this time.".



Tony:

"At least vampires and other canabalistic undead have a motivation to keep the human race a going concern. Other immortals could take us or leave us (except maybe for a stable of the most sexually desirable humans, just for fun)."

If the immortals can no longer reproduce, then they will need pre-immortalized humans to do their reproducing for them, unless their immortality is 100% perfect.

If immortals can reproduce and managed to get the "eternal beauty" deal rather than the "decaying corpse" deal, then it's not clear why they'd bother to use humans for their sex drives... except maybe for the sake of fetishizing virginity. That would require a constantly renewable population where members don't stay eligible for long...

Anonymous said...

(SA Phil)

Hmm is that really the way to determine the sound energy?

If a Submarine produces 40 Watts of sound, why is that any different than say a Stereo producing 40 Watts of sound?

It seems to me that if an Ohio Sub puts out 40 watts it no louder than a 40 watt stereo -- which means its super quiet for a 5000 ton ship.

40 Watts is 40 Watts, right?
------

Of course if the sub turns sound into heat then sinks it in the water - it is doing what a Spacecraft can not do.

But from what I understand Subs have to shed a lot of heat into the water all the time - and tend towards uncomfortably hot (~80F) inside even so.

jollyreaper said...

How long would immortals stay in their refuges? I guess it would depend on several factors.

1. Do they retain their capacity for learning? How much of the conservative behavior in senescent humans is due to a decreased ability to learn in old age? Even in our youth, it's easiest to pick up new languages as children and becomes increasingly difficult the older we get.

2. How much do old memories fade? Some immortal tropes have everything after a human lifetime getting fuzzy. A 300 year old immortal remembers the last 60 years clearly but things fade out after that. Reading his diary from 200 years ago is like reading something that happened to someone else.

3. Everyone's different. With us here mortals, some people never manage to grow up. Some people get stodgy old mindsets quickly. Some manage to keep themselves in a child-like state of curiosity even when working with weighty concepts and can keep that up well into old age. Presupposing there's no elitist selection process for immortality, I think you'd still have that mix.

As for sexually-reproducing immortals wanting to keep humans around, it would be vanity and ego. What fun is it to be a god if there's nobody to lord it over? And if we're talking about any sort of immortality that brings sterility (vampires or whatever) then you'd call the mortals the living bloodline and the immortals would be breeding potential heirs. The young mortals would be living in constant evaluation to see if they're worthy of making the cut.

Thucydides said...

"Space Warfare XIV: Things As They Ought To Be"

Zombies, Vampires and elves, oh my....

I suppose we can think of Zombies as a form of biological warfare, using some sort of virus to disable the higher functions of the brain or induce rage, hallucinations or other noise into the cognitive functions of the brain.

"Elves" do bring up an interesting discussion, since life extension is one of the goals of todays biological sciences. Immortal beings have been well portrayed in literature, especially by JRR Tolkien. After all, his Elves actually doremember and were participants of events near the creation of Arda, and fight great battles, experience love, jealousy, loss etc. There is no real reason to expect immortal humans won't experience similar experiences and emotions. Wars might become endless insurgencies as grudges and wrongs are traded and erased in blood. Dealing with people in the Balkens who recited the story of the Battle of Kosovo Polje as if it took place during the 1990 civil wars (it was fought in the 1389) was like dealing with insane people who were passing a grudge over may generations. IF we had to deal with the participants, it probably would be a totally alien experience. The Pashtuan people in Afghanistan hold similar attitudes, although blood feuds are more limited to personal issues (sheep stealing, murder, kidnapping) and cultural restraints like Pashtunwali.

Just trying to get away for a fresh start and escape will be a motive for "Elves", although the cycle will repeat again and again. Waves of space colonies consisting of new generations of Elves fleeing established feuding from previous generations might well be enough motivation (while fighting goes on in each colony, it does not seem likely most fights will travel; space war in the sense we have been taking about sill be rare).

Milo said...

Jollyreaper:

"2. How much do old memories fade? Some immortal tropes have everything after a human lifetime getting fuzzy. A 300 year old immortal remembers the last 60 years clearly but things fade out after that. Reading his diary from 200 years ago is like reading something that happened to someone else."

This is largely an excuse to make immortals more humanlike, by authors who aren't confident in their ability to portray a real immortal.

But there is merit to it. Humans don't retain memories from their childhoods, and even more recent memories can become fuzzy after a while. But really significant memories tend to persist - so it isn't so much forgetting old memories as it is filtering out the most important details. Really life-changing incidents are probably never forgotten, barring medical amnesia.


"Some manage to keep themselves in a child-like state of curiosity even when working with weighty concepts"

That's us, right?


"Presupposing there's no elitist selection process for immortality, I think you'd still have that mix."

Even if you have a selection process, there's still going to be differences between people. There are many variations on a theme.



Thucydides:

"Wars might become endless insurgencies as grudges and wrongs are traded and erased in blood."

Having "endless insurgencies" is going to cut short your average lifespan pretty quickly.

KraKon said...

Detection ranges:
According to the wikipedia article on minutes of arc, it is said that a telescope using a 10m mirror and adaptive optics can have a resolution down to 0.05 arcseconds...twice as good as the Hubble telescope. That is a viable baseline for the beginning of a fight between accelstars (or anything with a laser on one side) in my universe. The platforms are stable, the crew doesn't have any hands or feet to perturbate the instruments, the drives are off and radiators are retracted to maximum coolness and minimum vibration.
This allows me to see an enemy ship side-on from (45m) 184000km away, head on (15m) from 61000km. Which is fine, as the main wapon system used has a maximal usefullness range fo 10000km, beyond that you have no chance of hitting the enemy.
This does however mean that in interplanetary space, ships zipping past at 400km/s relative only stay inside of weapon range for four minutes, then they're gone past you and towards your homeworld/orbtal station/space habs... If you're defending something, the enemy will only stay within your sensor range for 8 minutes, which is pitiful. No interplanetary fights!
But a more difficult problem has arised: the missiles I use (I slightlt modified them, performance is the same but they can survive much longer...around 8x longer) are 30cm in diameter. This can only be detected from 1200km away. If the enemy decides to accelerate small, fast 80km/s waves of kinetics, you only have 15s to intercept them!
The problem is (other than happily pushing more laser coolness down the trash drain) that these missiles are bright flares that can be detected from a few AU away. So what is it on the defender's side? He can see the missiles on IR, but can't shoot at them because his beam will randomly wander over the whole missile's length?

Oh, and afterwards it get worse (no, not Evil Website!). The combatants have to accelerate by riding vibration-rich nuclear pulses, they have to launch kinetics, they have to use their 20GW generator coninuously (and get a combined heat load of 8GW, hopefully most of it stays in the drones), extends and retract radiators, release vaporized flash coolant, roll, pitch, get hit by 32GJ missiles, have their fast rotating armor get scorched unevenly...hell compared to the air-conditioned lab where the targeting systems were designed.

KraKon said...

On immortal technoeleves:

What we'll see is a spacefaring civilization expanding in waves of younger and younger generations. The core of the empire (its going to be a gerontocracy) is populated by the extremely rich and the eldest (synonyms here), for whom staying on Earth is a status symbol. Moving outwards, we have the second immortal generation that was forced outwards but set their prying eyes on their elders (wishing for heart attacks). Further and further out, we have younger and younger generations that move outwards at the rate of population increase. For the youngest generations, government help for colonization and the such, giving away °0% interest contracts for settlement and free habs to start of with...will be needed to encourage them to move out. As the colony matures, and the eldest get richer, they'll wish to move back in, back to where all the money is. Problem is, people don't die off, and modern tech means there's a lot less accidents. Result: the empire has a net increase in size.

Warfare WILL be more frequent. It won't be massive orbital bombardment against the homeworlds to make extra living room, it'll be assassination attempts, black and secret operations, little stuff that takes out the leaders. Why? Because you take out Big Head Guy, his whole administration, clan, suite, whatever has to move out. You've now ensured a spot not only for yourself, but your whole extended clan/family/business partners.
In other words: Corporate mob wars between professional guards and mercenaries. As we move outwards, war is less frequent and more conventional, but we won't shrink from nuclear winters as all we'd have to do is wait for the next generation to fill in the spot.

Thucydides said...

Condottieri wars and a permanent Italian Renaissance in Spaaaaace?

Love the setting

jollyreaper said...


This is largely an excuse to make immortals more humanlike, by authors who aren't confident in their ability to portray a real immortal.


Yes, but not just that. There would be a finite limit to the scale of human memory given our brains I would think and I wonder if making the memory limitless would be a separate handwave from immortality.

What I like is the idea of an immortal who changes with time who might not even recognize his earlier self. Say he was trying to live as tradesman and some great war happened and he lost his village. He draws upon his experiences and raises a partisan army to wage war on the invader. He's savage, brutal, slaughtering everyone. Ivan the Terrible territory, fields of impaled bodies. The king who couldn't be bothered to provide forces to prevent the slaughter of the village is ready to kill him to dispose of a potential rival. The immortal wisely disappears before this happens. Years and years go by, his memories of the loss of his family fade. He keeps a diary to remind himself of things too important to forget. But anything he chooses to forget he does not write down and it will fade. Hundreds of years later, he knows of the legend of the vengeful monster of that war and does not realize it is he. No longer having the memories of his losses so fresh, not feeling the justification for monstrous acts, he is not in a position to understand his former self.

Hmm. I suppose this is basically just Memento stretched out a whole lot longer.

jollyreaper said...


Warfare WILL be more frequent. It won't be massive orbital bombardment against the homeworlds to make extra living room, it'll be assassination attempts, black and secret operations, little stuff that takes out the leaders. Why? Because you take out Big Head Guy, his whole administration, clan, suite, whatever has to move out. You've now ensured a spot not only for yourself, but your whole extended clan/family/business partners.


Makes a whole lot of sense. Stable mortal governments need traditions for handling succession and a handover of power. The imperial way of doing things with countries changing hands due to marriage, succession wars upon the death of a ruler, dividing territory amongst sons, that's insane. For all the problems involved, the post-monarchical way of handling nation-states makes a lot more sense. And you see why you don't want the state to be embodied in an individual when you look at the collapse of dictatorships. But when that individual is immortal... You have ol' Don Corleone running his family for a few centuries, people will get kind of used to things being that way. His loss would be all the more devastating. And loyalties would be to people, not institutions. Alliances made between clans, favors owed, they would be from head to head, non-transferable, because that's the way it tended to go with absolute monarchies.

One premise I liked for demographically-driven warfare was an alternative take on the Kzin. Warfare used to take place on the planet and was very destructive. They breed fast and so there's always a huge surplus of males to get rid of. When the dumb aliens try to enslave the Kzin and are slaughtered, the emperor realizes things are going to have to change. It's fine to have the fights with fang and claw but not with lasers and nukes. Warfare is banned on the homeworld. Ok, fine. But what to do with the population pressure? The young males want territory, they want females, they want to start their own prides. There's not enough to go around.

The only solution is going to war against the humans. Conquering inhabited worlds? Why not find some empty ones. Ah, that's because the emperor doesn't want to risk a rival power base. He lets a whole planet become as powerful as homeworld, they're going to start wondering why an equal should submit. He needs to get his surplus population screaming and leaping at a hard opponent and constantly facing counter-attack as the humans try to retake their lost colonies.

And what would make it absolutely perfect is if the Kzin technology is actually far advanced compared to the human tech. The emperor and the old pride leaders all know it but keep it under their hats. The tech they're releasing to the young males heading off to war is scaled to be at a slight disadvantage compared to the humans. If the humans ever attack the homeworld, the imperial guard breaks out the top-shelf stuff and would smash them to bits.

So the worst possible outcome from the emperor's perspective is for his forces to do too well, actually conquering humanity. Because then that means there's going to be a whole ton of rival power bases forming and would inevitably lead to a kzinti civil war.

So I'm imagining the delightfully absurd situation of a losing humanity getting covert aid from the imperial kzin. Here's some new tech, here's the battle plan for our attacking forces. Make a good show of it, okay?

KraKon said...

"Makes a whole lot of sense. "

YAY recognition.

"His loss would be all the more devastating. And loyalties would be to people, not institutions. Alliances made between clans, favors owed, they would be from head to head, non-transferable, because that's the way it tended to go with absolute monarchies. "

It also works the other way round. Grudges can be held forever...the supreme rules could offend you or give the raise to someone else, forget about it because he is administrating the whole empire, but you, you'd have centuries to prepare and exact a revenge. You could build up a fortune, prepare a small army, find a way to possess those illegal antimatter bombs, all for the sake of wiping out that guy who bad-mouthed you when you were young (er).

I also see the King's Court political comedy coming back in force. If the King likes you, you've just secured a spot as viceroy of the new domain, a position you'd otherwise would have to wait a few centuries for. If your superior doesn't like you, you could work your ass off for decades and never advance.

Implications in other fields with immortality are interesting.

Science and culture for example. Imagine Mendelev, von Braun, Pournelle, Einstein AND Imhotep were all alive right now. Instead of half-assed technological breakthroughs for commercial purposes appearing every year, we'd have a group of elites made up of scientists and thinkers that would work upon their discoveries for centuries, as someone's masterpiece of life's work would become highly relative...
We'd also have FOR SCIENCE!!! mad genius experiments x100....

KraKon said...

"The only solution is going to war against the humans. Conquering inhabited worlds? Why not find some empty ones. Ah, that's because the emperor doesn't want to risk a rival power base. "

An easier solution would have been sending the new generations to further and further away planets, let them develop a stable industrial techbase (you can skip the bleeding edge tech though ;) ), then...let them war against each other. That way the planets would never develop billion-number populations or huge space armadas that would threaten you, your secret ops would make sure that they are always occupied enough with each other to never reach that point.

IF, and it will probably happen, a group of planets make an alliance, stop warring and are unreceptive to your infiltrated warmongering advisers, you let them develop for a bit, find an excuse to make war with them and slag them from orbit. Or from several solar systems away, flavor to the required extreme overkill.

End result: you've removed a threat, made the rest of the colonies cower in fear (while they might do the same to your homeplanet, you can retaliate as the central empire is much larger than the rest of the colonies combined, it is impossible to wipe it out on the first hit..make sure of that) and ensured peace and such and such back home for a few decades, good PR.

"So I'm imagining the delightfully absurd situation of a losing humanity getting covert aid from the imperial kzin. Here's some new tech, here's the battle plan for our attacking forces. Make a good show of it, okay?"

Can I use a word that pops up very often here? Please?
Okay.
The situation you describe is 'metastable'. Eventually, there will be contact between the humans and the Kzin invaders, and eventually the humans tell, or the Kzin get to see, that the Empire is supplying humans with the latest technology and the battle plans of the puppet army; fulminating conquerors go back home and start a civil war anyway.
This is because even if the humans are happy to fend of invaders every time with the help of the Empire, they aren't happy there's recurring invasions that sap its resources every time an alien civilization needs to vent off its excess population. Found a way to start a civil war at the Kzin's homeworld? That's surely better than having to maintain a defensive fleet, support losses and waste resources, all on tech provided by the enemy (thus riddeled with bugs and backdoors)!

jollyreaper said...

An easier solution would have been sending the new generations to further and further away planets


Nope! Because we want squishy humans in the story. :) It's not meant to be a good decision on the part of the Kzin it's supposed to be very flawed. It's supposed to be the kind of thing that everyone but the guys directly involved with it will see as a terrible mistake.

End result: you've removed a threat, made the rest of the colonies cower in fear (while they might do the same to your homeplanet, you can retaliate as the central empire is much larger than the rest of the colonies combined, it is impossible to wipe it out on the first hit..make sure of that) and ensured peace and such and such back home for a few decades, good PR.


Be fine for a humans v. humans story but the original idea was explaining a plausible alien invasion story. If you run with the Niven explanation of humans and kzin being similar because of genetic seeding by precurssors and so forth... the deliberate withholding of super-tech to keep the fight even helps rationalize the apes and angels argument.

Can I use a word that pops up very often here? Please?
Okay.
The situation you describe is 'metastable'.


Of course it is! That's the whole point. The whole setup is to lead you to think "Oooh, this can't possibly end well."

Metastable is a good critique against someone arguing for a perfect form of government or an ideal economic system or something they're proud of describing as a timeless good thing. Metastable is actually a compliment when someone is laying out a setting for a story that will be "interesting" in the Chinese sense.

Someone describes the late French aristocracy. "So the nobles sound like real bastards and are putting the peasants under too much pressure. This is a flawed society. It's metastable at best. Something's gotta give." And that someone smiles. "Exactly! See, I've got this story called Tale of Two Cities that will be about when the other shoe drops and you get a revolution."

jollyreaper said...

Eventually, there will be contact between the humans and the Kzin invaders, and eventually the humans tell, or the Kzin get to see, that the Empire is supplying humans with the latest technology and the battle plans of the puppet army; fulminating conquerors go back home and start a civil war anyway.


In the original Man-Kzin Wars setting, the idea was to breed aggression out of the Kzin. The Puppeteers triggered the whole war and the Kzin kept screaming and leaping until all their dumbest, most aggressive members were killed off. The only ones left to breed were the saner, civilized cats.

So yes, the cookie starts crumbling in stages.

1. War starts, humans fight back. Some early victories.
2. War goes on for a few decades, back and forth. Humans fear stalemate.
3. War starts to go badly, kzin are doing too well.
4. Imperial Kzin intervene with tech and intel and stalemate is reestablished.
5. Eventually the younger kzin start piecing things together and realize they're being played for dupes.
6. Kzin civil war, humans better pick sides. The young kzin like the idea of galactic conquest and if they win the war, they'll have the tech to come back and smash the hummiez completely.

That's a good dramatic arc. We've had human examples of wars going on for hundreds of years in fits and starts but that's not including planet-smashers and other kinds of WMD's.

This is because even if the humans are happy to fend of invaders every time with the help of the Empire, they aren't happy there's recurring invasions that sap its resources every time an alien civilization needs to vent off its excess population.

Oh, the hummiez will be pissed when they find out what the real story is! They could accept fighting the good fight against the alien horde. They could accept help from rebel aliens who feel sorry for them and disagree with the actions of their fellows. But used as population control in some strange, Kafka-meets-mongol-hordes scenario? Oooooh, you're talking some mad hummiez!

Found a way to start a civil war at the Kzin's homeworld? That's surely better than having to maintain a defensive fleet, support losses and waste resources, all on tech provided by the enemy (thus riddeled with bugs and backdoors)!

Not sure how it would go but the whole idea is that the hummiez are furious about the whole thing and are looking for a way to finally assert some control. I mean hell, imagine the sense of indignation when they find out that the fight they've been bleeding and dying for over the last 20 years against an enemy they can only just barely defeat is all because the enemy has been holding back their strength the whole time. Cat and mouse? Argh! And the humiliation of accepting the help from the imperials...

Tony said...

Re: jollyreaper

It's already been established as canon that the kzinti were Jotoki barbarian mercenaries who rebelled against, then enslaved their masters. They only ran into humans after enslaving several other races. The encounter with humanity was accidental and the first Man-Kzin war was basically a local initiative that the Patriarch was unaware of until it was well underway.

Also, the biggest human advantage has always been that kzinti are impatient. Now, kzinti internal politics definitely exacerbate this, but only in the sense that they egg each other on to begine the attack before they are really ready. There's nothing to suggest there is or need be some backstage maneuvering to get them to screw up their timing.

Finally, if rebellion against the Patriarchy is such a big issue, why would the Patriarch be constantly trying to acquire illegal (under the terms of peace treaties with Humans) hyperdrive spaceships and distribute them throughout the Patriarchy domains? They would, after all, make rebellion easier.

Scott said...

To some extent, you're right. Subs can afford to convert sound to heat, and then conduct that heat into the ocean.

That's why I included 300K radiators in the original reply.

Does anyone have a better guess for how much heat energy you'd need to get rid of at 300k than ~4MW?

Raymond said...

Scott:

4 MW seems far too high just for waste heat from life support - you'd have more waste heat just from power conditioning - and 300 K is around the equilibrium temp for components exposed to the sun at Earth orbit. You'll probably want to spend a little of your excess energy production on a heat pump, and radiate substantially higher than that (preferably close to your powerplant's heat rejection temperature).

Raymond said...

Just for comparison, the heat rejection capability of the ISS' P1 and S1 truss radiators is a total of 70 kW - and that's for the majority of the ISS' heat generation, which is mostly from the power conditioning units IIRC.

So, if we're trying to reduce vibrations for a laser, make sure to limit the number of connection points between the laser mirrors and the powerplant, power conditioning/distribution unit, and hab unit, and then make sure to put in active noise dampening at the connection points which do exist.

Anonymous said...

Scott,

To some extent, you're right. Subs can afford to convert sound to heat, and then conduct that heat into the ocean.

===============

About 10 years ago I spent the night in a World War 2 sub in Lake Michigan -- in febuary.

Since the engines didn't run - it was quite possibly the coldest "indoor" place on earth.

--------
As to the heat radiators - I am sure they would work for noise generated heat as well. Which is probably low compared to the reactor and laser heat.

The pumps, etc, would probably used some sort of advanced fluid dynamic design to minimize mechanical noise also.

(SA Phil)

jollyreaper said...

It's already been established as canon that the kzinti were Jotoki barbarian mercenaries who rebelled against, then enslaved their masters.

I know that. I said it was a different take on them, not trying to stay within the original premise. The Kzin were fully committed to the idea of the war. The twist would be what if the war was a con played by the imperial kzin against the lesser families? I brought it up because of the talk of population pressures and fighting for territory with the elves subthread.

Rick said...

Metastability: It's a bug AND a feature!

The danger is creating TSTL bad guys and therefore books that get hurled against walls with extreme force.

Milo said...

Jollyreaper:

"Metastable is a good critique against someone arguing for a perfect form of government or an ideal economic system or something they're proud of describing as a timeless good thing. Metastable is actually a compliment when someone is laying out a setting for a story that will be "interesting" in the Chinese sense."

Oh, very true. But coming back to immortals, just how metastable can those get? How likely are you to have a sudden change in circumstances when it's the same old, wise people who remain in control of stuff?



Rick:

"TSTL"

?

jollyreaper said...


Metastability: It's a bug AND a feature!

The danger is creating TSTL bad guys and therefore books that get hurled against walls with extreme force.


Ooooh TSTL too stupid to live. Agreed. There's a fine line (or wide chasm, depending on how it's written). We're running into Twain's observation about fiction having to make sense but reality is under no such constraints.

There are endless examples of people, empires, corporations, etc sewing the seeds for their own downfall. The whole trick is making the downfall make sense. Arguing that the mistake is too stupid to possibly be made means Japan never would have attacked the US in WWII. The history shows us how such a horrid confrontation was inevitable. That's why tragedy works so well in fiction -- it never should have had to be this way. Romeo and Juliet could have been a comedy of love conquers all if everyone had been sensible. Hell, there wouldn't have even been a long-standing feud if logic conquered all first.

I think the short answer to all this is "A proper villain is the man driven to do horrible things for greed or vanity. Too stupid to live would be him explaining his plans to the hero and then leaving him in a death trap he can escape from rather than just skipping the monologue and shooting him in the head."

Tony said...

jollyreaper:

"I think the short answer to all this is 'A proper villain is the man driven to do horrible things for greed or vanity. Too stupid to live would be him explaining his plans to the hero and then leaving him in a death trap he can escape from rather than just skipping the monologue and shooting him in the head.'"

That's a cardboard cutout villain. What good fiction needs is an antagonist that is manifestly not gratuitously evil, greed, or vain -- he/she/it just has goals/imperatives/behaviors that run counter to the good of the protagonist(s).

The shark in Jaws is a good example. It wasn't good or bad; it just was.

Likewise Darth Vader, after we learn his history. He had some serious issues that drove him in a certain direction and it took him a whole life to overcome them.

That's why WWII fiction has certain conventions. It rarely deals with the Japanese or German high commands, because they are generally agreed to have been batshit insane. When it deals with the Allied high commands, the conflicts take one of two forms:

1. Principled men who have conflicting imperatives, but who all want to do the right thing, or

2. Principled men against incompetents or loonies.

At lower levels, the enemies are either too anonymous to be anything but a force of nature, or honorable fellow warriors who are in the same boat as the friendlies. Sometimes you both of these in the same book, as in Cross of Iron.

jollyreaper said...

I'l clarify my villain comment. You can have barking mad caddies like the joker, amoral and interesting monsters like Hannibal lecter, proper bastards who are good at what they do like Otto Skorzney, unsympathetic total monsters like Beria whom even Stalin found distasteful, banality of evil types like Himmler, your charismatic types who descend into self-parody, madness and suicide like Hitler. My personal favorite is of course the sympathetic villain who finds himself on the other side of the war like a southern officer who hates slavery but can't bring himself to fight his own state. Every approach is valid and can yield good drama.

The only thing I don't want to see is the facepalm crap that gets entries on tvtropes. No monologuing. No James Bond death traps. Read the Evil Overlord Guide. Keep mistakes in the realm of believability and NOT due to author intervention. Hitler tries to turn the 262 into a bomber because he's obsessed with offense, not because it takes the pressure off our characters in the RAF. He gives up on Sea Lion and invades Russia because he overestimates how weak Stalin is, not because of deus ex machina tinkering. If your characters are in an infantry unit slated for the first wave of the Japanese home island invasion, the a-bomb really does seem like a deus ex machina but it's just good luck on their part.

It's easy to do this with historical fiction because we know how things went. It's harder for completely fictional settings but that's the challenge. I'd still have trouble buying something like Midway as fiction. I've already mentioned how hitting the rudder on Bismarck seemed like a million to one shot though rudders do seem to draw more hits than sheer chance would warrant.

KraKon said...

"I'l clarify my villain comment. You can have barking mad caddies like the joker, amoral and interesting monsters like Hannibal lecter, proper bastards who are good at what they do like Otto Skorzney, unsympathetic total monsters like Beria whom even Stalin found distasteful, banality of evil types like Himmler, your charismatic types who descend into self-parody, madness and suicide like Hitler. "

The complete panopoly of convincing antagonists! There's also the conflict-of-interest villians who have to choose between conserving their 'good side' and observing their loyalty pledge, and my favourite (more anti-hero than villian), a rational character that does the logical thing and not the right thing. Kudos if he saves the brave hero in the end.

"The shark in Jaws is a good example. It wasn't good or bad; it just was."

No...that shark was pure evil. It came up with a master plan to escape, and ended up in a self-destructive chase hunting humans down to the last one instead of enjoying its new found freedom and eating the little fishies; its also the view most sf authors have on really aliens-they not with us (because they're alien) but then they must be against us! Cue giant bugs trying to move from a hydrogen-based organochemistry to a human-based feeding cycle.

"That's why WWII fiction has certain conventions. It rarely deals with the Japanese or German high commands, because they are generally agreed to have been batshit insane"

The film Valkyrie with Tom Cruise (it was passable) says otherwise; the main reason we don't depict high command because fliming office scenes with fat men in uniforms drooling over uncomprehensible statistics and tactical maps ain't so fun as catching Joe American having a Cuban cigar in the middle of a firefight. +10 movie points if he lights it with burning napalm.

KraKon said...

PS: Why no return on the brain-in-a-jar crews? It seems today that major advances in medical tech allow such crews to appear BEFORE ravening beam of death laserstars and interplanetary conflict.

ElAntonius said...

Tossing something for the fire:

Navy Laser

Relevant quote:
"Hats off to the U.S. Navy because that is very, very impressive," he said. "It was pitching and rolling and yet they got this very fine beam to focus on one part of an engine casing. That they managed to keep the energy in one place is remarkable."

Raymond said...

Krakon:

I, for one, am perfectly fine with brain-in-a-jar concepts - it seems like an implicit constraint on Rocketpunk, however, to minimize the human modification.

Thucydides said...

Oh, very true. But coming back to immortals, just how metastable can those get? How likely are you to have a sudden change in circumstances when it's the same old, wise people who remain in control of stuff?

1. Other immortals on the home planet might also want to get in control of stuff, hence the Italian Renaissance trope (“Man these Borgia’s can hold a grudge!”).

2. The “elves” seeking new worlds might discover that they either don’t exist, are too rare or cannot be terraformed with the available resources and head back to the inner Solar System.

3. The first generation of elves are still essentially human, being recipients of some advanced biotechnology or medicine, subsequent generations might not be fully “human” as we understand the term and thus have different and conflicting motives from the initial waves of immortal humans.

4. Immortality is very hard to do so only a limited number of people can ascend to elfhood, they become inhuman to the majority of human beings and conflict ensues (the elves have a massive compound interest advantage is accumulating resources, and endless patience in dealing with human insurgencies)

Enjoy

Raymond said...

Elves. Bah. I defer to the Evil Website.

Our Elves Are Better
Can't Argue With Elves
Screw You, Elves!

KraKon said...

"I, for one, am perfectly fine with brain-in-a-jar concepts - it seems like an implicit constraint on Rocketpunk, however, to minimize the human modification."

There aren't any MAJOR modifications in the brain-in-a-jar concept, we've only removed the stuff that they don't need. Plus, the BIAJ allows us to have humans on a ship-restricting yourself to full body squishy humans means you won't have ANY humans on warships, because the disadvantages of a whole human habitat designed for a multi-year mission with 10+ crew just vastly outweigh the cost and complications that drones have. Furtehr in the future, the balance will be even worse. Human habs will be lighter and easier to accomodate thanks to ever more powerful drives...except that computer and drone technology adavances much faster. Just rad-hardening what we have in our laptops right now will suffice for a long time.

"3. The first generation of elves are still essentially human, being recipients of some advanced biotechnology or medicine, subsequent generations might not be fully “human” as we understand the term and thus have different and conflicting motives from the initial waves of immortal humans."

I see it slightly differently. The general concept is true, but there should be four bands, not two, from the center. The hub (band one) will be the oldest and most technologically-dependant region of the Empire. Since production and resources are delocalized, it can afford to have structures that do not sustain themselves. The planet-wide city trope is a good example of this. Here, the people can affordd to have extensive modifications to both body and society, a kind of ultraliberal capitalist techno/gerontocracy. The richest seem decidedly alien here.
The second band is the one we will recognize the most, to on eexception. The people here have a stable base for their industry and society, but are not so rich and powerful as to allow the excesses of the hub. The major difference here is that social class seperation moves geographically over time. On Earth, people born today will live on the same land there grand-grand-grand fathers did. The eldest die out, the new replace them, that's why today's major cities are stablilizing in size. In an immortal society, there just isn't enough space for people, so second band inhabitants either get rich and move in, become too poor and have to move out, but never stay still. I mean, you've got centuries to get rich or lose all your money, right?
Third band is the strangest to us. These are the people who were rejected by the inner band societies, who were pushed out when young, who had to adapt to etching out an existence from nothing. Other motivations, other constraints and we get a whole different society.
Fourth band will be difficult to determine. Either the newest generations are still suffering from inadequate preparation to their new environment, where they may still be living in habs as the planet below them is being terraformed. That will make them lag behind a few centuries in techlevel and industrial stability- therefore on a recognisable level for readers- or they will be the infinitely patient, we just failed this century long project its okay lets start over again attitude that we won't recognize...or they'll be hippies.

KraKon said...

"Elves. Bah. I defer to the Evil Website.

Our Elves Are Better
Can't Argue With Elves
Screw You, Elves!"

Why?! Oh why, raymond, you just made me take ages to finisht he previous comment. That website is a ditruption in the space-time continuum; you're a click away from time being accelerated 1000x for the rest of the evening!

KraKon said...

Any comments on the detection range issues I mentioned upthread?

Rick said...

There aren't any MAJOR modifications in the brain-in-a-jar concept, we've only removed the stuff that they don't need.

As Ronald Reagan once said, "Where's the rest of me?" Brains in a jar require an awfully big cultural change, and lots of people (like me!) would have a negative bias going in about a culture that preps its troops that way.

In any case, my gut feeling is that most of the colorful future medical breakthroughs are this generation's equivalent of jet packs and suborbital rocket liners. YMM, of course, may V!

jollyreaper said...


As Ronald Reagan once said, "Where's the rest of me?" Brains in a jar require an awfully big cultural change, and lots of people (like me!) would have a negative bias going in about a culture that preps its troops that way.


I'd say that the big cultural shakeups will already be worked out before the brainships are built.

There's a couple of technologies I think would be tied up with brain jars:
1. Brain transplants
2. Full body human cloning
3. (potentially) mind backups and uploads

That last one will be a kicker. You'll divide human existence into before and after. It'll be the biggest thing to hit the genus since consciousness.

Charlie Stross and others have explored the concepts involved there and there's plenty about it on the Orion's Arm site.

The concept of individual personhood is dead. Do your clones have human rights, are they still you? Does any one instance of you get priority over the other -- oldest clone is the legal you? Can you own your own clone, enslaving yourself?

The only shortcut around that whole mess would be if we could perfect brain regeneration -- biological immortality. Then we're right back in the space elves camp but with the twist of knowing that the interstellar warships are run by brains in jars.

There's another potential look at this, of course -- what if you can surgically extract the brain and put it in a jar but not put it back? That means that becoming a brain jar is a permanent, irreversible thing. Sounds like a punishment. Not exactly the sort of thing you'd want to do for recruiting guys to fly your giant warships with ravening beams of death. I have a really hard time imagining recruiting large numbers of people for this sort of thing by choice. So then you're talking about going the Dalek route -- you breed an entire line of people who are meant to be nothing more than brains in jars, know of no other life than being plugged into the ships.

Raymond said...

jollyreaper:

I don't think brain-jars necessarily lead to uploads. And frankly, as interesting as some of the complications are, the concept of brain uploads in SF has become tied to a certain idea of a post-scarcity society which, if I can be heretical, I think has run its literary course.

I think some of the body-swapping corollaries of brain-jars still have life in them, but with no functional immortality and bodies built or grown the hard way. In fact, I think the concept is a nice little twist to Rocketpunk. But YMMV.

jollyreaper said...


I think some of the body-swapping corollaries of brain-jars still have life in them, but with no functional immortality and bodies built or grown the hard way. In fact, I think the concept is a nice little twist to Rocketpunk. But YMMV.


So when not in the ships would the brains be using full body prosthetics ala Ghost in the Shell? If we set aside things like the impairment of the body and neural degenerative diseases, how long should a brain be good for? 90 years? 150?

Scott said...

It seems to me that if an Ohio Sub puts out 40 watts it no louder than a 40 watt stereo -- which means its super quiet for a 5000 ton ship.

Ohios are super-quiet, and they're 19,000 tons.

=====
As far as the heat issue goes, I just can't see how to get the lifesection radiators up to 1600K. 350K is reasonable, since that's about as hot as the hot side of an AC unit. If the ISS radiates 70kw with a crew of 3, then something with 2 orders of magnitude more systems (like a military ship) will have ~7MW waste heat.

Raymond said...

jollyreaper:

No idea how long the brain can last in theory, barring senility etc. I would surmise, however, that full-body prosthetics would make offworld work (and life support) easier.

Scott:

1600 K was the cold-side temp of a vapor-core space-optimized fission reactor design I've seen a couple of places. At that temp, the same radiator area you listed can emit 2 GW of waste heat. Even the gas-cooled solid-core designs have cold-side temps of at least 800 K.

If you have spare power from the on-board reactor, you can run a heat pump to boost the rejection temp (at the cost of additional energy, of course, but it does make the radiators more efficient), or failing that, you can at least run the coolant through a heat exchanger linked to the reactor coolant loop, and get your temp up that way (at least 800 K).

I wouldn't put 4 radiators at 90 deg, though. Two sides will be facing the sun at all times, which makes rejecting heat at 300 K pretty much impossible.

Milo said...

KraKon:

"PS: Why no return on the brain-in-a-jar crews?"

Because people tend to enjoy having a body.

Furthermore, besides intelligence, opposable thumbs are one of the most useful features humans have. Humans are dextrous beings that can move in places where robots have trouble and can easily manipulate a great variety of tools. A brain in a jar would eliminate many of the advantages of having a human on site, besides that of having command decisions close enough to not suffer lightspeed lag/communications cutoffs from occultations.

Maybe you can build a good humanoid robot for your brain to pilot, but if you're going that route anyway, and you also have biomodification technology to make brains-in-a-jar in the first place, then why not take the simpler route of altering humans to have lower life support requirements while retaining the same baseline design?


"multi-year mission"

People aren't going to like flying multi-year missions, no matter what. It has nothing to do with life support requirements and everything to do with terminal boredom. Few military missions are going to be that long (without crew rotations).

The one type of ship that I can see willing to accept such durations is a colony ship, which of course requires colonists capable of reproducing once they arrive at the destination. Which is a good reason to keep working bodies. (Maybe you have cloning machines, but that's considerably less fun.)


"On Earth, people born today will live on the same land there grand-grand-grand fathers did. The eldest die out, the new replace them, that's why today's major cities are stablilizing in size. In an immortal society, there just isn't enough space for people,"

I am assuming that the immortals have a lowered birth rate to go with their lowered death rate. While immortals with a sufficiently easy time expanding to new lands might well breed like rabbits as you describe, I expect that this will not apply to most immortals and they will not have a major youth surplus.

(Incidentally, terminology note: I've been using "elves" to refer to a hypothetical species that has been naturally immortal since their stone age. Futuristic posthumans that became immortal through the power of technology will share many of the same tropes, but not quite all of them, so it's useful to distinguish the two. Elves are easier to think about in one sense because we don't have to make a technology forecast thousands of years into the future in order to have really old immortals to play with.)



Raymond:

"I don't think brain-jars necessarily lead to uploads."

Oh, definitely not. My gut instinct says that mind uploads will be significantly more difficult to pull off than brains in jars, agelessness (i.e., immortality that is still succeptible to permanent death by misadventure), and other body modification concepts. (Significantly more difficult means "I could buy it if you say that we will accomplish the latter but never the former, and even if we do eventually accomplish both then the former will come notably later.".)

If mind uploading does exist, then brains in jars will probably be nonexistant or obsolete, replaced with digitized brains running electronically (which will have even easier life support requirements, and be easier to upgrade by for example increasing their clock speed).


"And frankly, as interesting as some of the complications are, the concept of brain uploads in SF has become tied to a certain idea of a post-scarcity society which, if I can be heretical, I think has run its literary course."

Quick! Someone write a story about the complications of property rights when multiple clones of the same uploaded person are vying for their fortune, in a culture that has enough scarcity for property rights to actually matter!

Raymond said...

Milo:

"Maybe you can build a good humanoid robot for your brain to pilot, but if you're going that route anyway, and you also have biomodification technology to make brains-in-a-jar in the first place, then why not take the simpler route of altering humans to have lower life support requirements while retaining the same baseline design?"

Two words: hot swappable.

The humanoid configuration isn't necessarily optimal for everything. Sometimes you want more armor or shielding, sometimes you'll want integrated thrusters, sometimes you'll want something wacky and weird. Best part? You can keep your original body.

"Quick! Someone write a story about the complications of property rights when multiple clones of the same uploaded person are vying for their fortune, in a culture that has enough scarcity for property rights to actually matter!"

There's a couple Calvin & Hobbes strips with the Duplicator - those are probably better than listening to future lawyers argue.

jollyreaper said...

Red Dwarf had the example of Rimmer duping himself and discovering that he is an insufferable smeghead that no one could possibly put up with. I'd previously posted the idea o a big bad who had clone backups with a dead man's switch. You kill him, a new clone decants. The heroes bugger up the signal so every clone decants. A hero would naturally cooperate with his other selves. The villain realizes all his clones will be killing each other because there can be only one, highlander failure mode.

Anonymous said...

Tony: I just finished reading your reply to my Zombie PSA comment; best laugh I've had in quite some time! Thanks!

Ferrell

Milo said...

What keeps getting laughs out of me is Jollyreaper's skit.

Anonymous said...

Milo, Jollyreaper, if not Robot Chicken, then maybe Monty Python?

Ferrell

Tony said...

Ferrell:

"Tony: I just finished reading your reply to my Zombie PSA comment; best laugh I've had in quite some time! Thanks!"

I thought it was a little stiff, but...you're welcome!

KraKon said...

"Of course it is! That's the whole point. The whole setup is to lead you to think "Oooh, this can't possibly end well."

I get it now :)
Seems worrying the Emperor's advisors didn't see that as clearly as we do.

"Brains in a jar require an awfully big cultural change, and lots of people (like me!) would have a negative bias going in about a culture that preps its troops that way."

I posed BIAJ (well, with the spinal cord and the bundles of nerves that directly leave the spinal cord) as expensive technology, and irreversible. Expensive, well, because handling the brain outside of its intended natural vessel is bound to have complications (how do you keep it alive during the transfer for one...). Irreversible because we've just intentionally cut every single nerve used to control a body. And we don't have magitech NerveGrow to fix you up. But the advantages are many, and troops are not obliged to go this path (okay, they are as only the best will be accepted to be carried over to the battlefield), and most people (space hab elites, rich people on the ground, anyone who's not a neo-luddite in colonies) do it willingly once they've got enough money.

"There's a couple of technologies I think would be tied up with brain jars:
1. Brain transplants
2. Full body human cloning
3. (potentially) mind backups and uploads "

Brain transplants requires you to cut out the brain, and rewire it back to another body. That includes every single nerve, every single tiniest blood vessel...it's not like a heart which we can leave to hormonal control, the brain is just too complicated. BIAJ just requires gross interfaces with electronics, Brain stem in a jar only needs you to find the ready made interface between the nervous system and the body rather than sorting out the much finer nerves inside the brain stem.

Full body human cloning...not really. Putting a brain in a jar doesn't require any bit of growing stuff. I DO have cloning, but not human cloning. What I clone is mass produced flesh suits, ie a near-human body a BSIAJ can have human experiences with. Commercial models are individualized and need complicated internal machinery to keep it alive (if we had perfect cloning, well...), the military and poorer people just go with the cyborgs.

Mind backups and uploads is again not a derivative of BSIAJs. They require mapping the whole brain (yes, every single of the hundred million billion or something nerve connections), modelling their still unknown chemistry on a computer, then running it alongside a sufficiently strong AI that can decipher just what the results mean. Uh uh, I'll leave that to wetware.

KraKon said...

"Sounds like a punishment."

Ouch.
The ad goes like this:
Pay this amount of money; we connect your brain stem to electrobio jacks that can convert chemical signals into electrical ones. This allows you to use any single adapted machine interface.
You go to war. We can afford to put you in the spaceship, and protect you for minimal cost (you're in a lead lined bank vault).
You will have access to top notch simulated environments during the dead periods.
When you get back home, the space industry is all open for you, human skills without the hab costs. If you want some skin, get a flesh suit and live like a human. Come back for repairs, recharge and suit replacement every 5 years.
Bored? Come back for more within your 100 year+ lifespan.

Extra advantages include being able to pilot commercial ships (with shoddy radiation shielding) for decades because you don't have a body to get radiation sick with, being able to connect for cheap/free to the planetary simverses on larger colonies (heck, just for trading at the speed of the processors), able to provide not cheap labor, but indestrictible labor, say, building up a colony that will accept future colonists on some desolate outpost or providing maintenance to an orbital mining installation without requiring a supply ship running back and forth....

"If we set aside things like the impairment of the body and neural degenerative diseases, how long should a brain be good for? 90 years? 150?"

I'd like to say that you'll die of old age, but without the heart attacks and cancers. The brain degenerates slowly due to its own chemical activity anyway, so yes, I'd set it to 150 years or such (the BSIAJ will be useless before this because, well, for all its advantages you don't want to send Old Pops up there to do the work).

"Because people tend to enjoy having a body."

I just made sure they can HAVE a body whenever they want.

"Maybe you can build a good humanoid robot for your brain to pilot, but if you're going that route anyway, and you also have biomodification technology to make brains-in-a-jar in the first place, then why not take the simpler route of altering humans to have lower life support requirements while retaining the same baseline design?"

Because, well, there's a lower limit to anything. I can feed a brain a few hundred grams of sugar, minerals and vitams and that's all that's needed to keep it alive. The simulated environment runs off the main ship computers, the electricity from the generator surplus. Humans, however have a much higher lower limit. I think you meant that we bioengineer human bodies to make them require less food, less heat, less air and such. Sure. But a full human body will ALWAYS require more space, more mass, more heat, more food and will be more fragile than a brain in a lead box. And that's even after giving up trying to keep the baseline design.

"everything to do with terminal boredom."

My universe has citizens spending most of their time hooked up to the planetary simverse back home, full bodied or not. It's their workplace, leisure suite, entertainment industry, telepresence interface, everything. It's one step after creating a paperless office-you bring it home.
So telling the officer that he'll be pretty much be doing the same thing during transit until the pew-pew starts can't be so bad!

KraKon said...

"Maybe you have cloning machines, but that's considerably less fun.)"

Blasphemy! Only the original AI colonization / deportation / humanity saving effort did that.

"I've been using "elves" to refer to a hypothetical species that has been naturally immortal since their stone age. "

Oops. Then I've been referring to elves as normal humans who discovered immortality tommorow, then we fast forwarded a thousand years into the future to see what they did with it.

"The humanoid configuration isn't necessarily optimal for everything. Sometimes you want more armor or shielding, sometimes you'll want integrated thrusters, sometimes you'll want something wacky and weird. Best part? You can keep your original body."

You hit it spot on.
I'm pretty sure a telepresence waldo with rather complicated manipulating arms can do the job of a human engineer much better (you can't crawl into that service tunnel worthy of Star Trek designs? Send your telepresence robot in).

On detection ranges: Really? 30cm detected at only 1200km away? That completely changes the face of kinetics exchanges here!

Thucydides said...

Point defense KKVs may have to be similar to this in order to be effective:

http://www.nuclearabms.info/Sprint.html

"If Sprint was a phenomenal missile, HiBEX was even more interesting in some ways. It was part of a project called Defender run by DARPA in conjunction with the Army for a last ditch ABM missile in a similar vein to Sprint. However, it was literally a last ditch missile and was designed to intercept an incoming RV at less than 6,100m (20,000ft) altitude. At that altitude, the incoming RV would be traveling at around 3,000m/sec (10,000ft/sec) so a very fast reaction time was essential to insure interception. In fact, HiBEX was designed to have exited from its silo within 1/4 second and it accelerated at over 400g.

HiBEX was only 5.2m (17ft) long and due to the high acceleration, the fuel did not last very long at all, so it was characterised with very short rocket burn times and hence a very short range. One of the problems with such a high accelerating missile was that of guidance, and the onboard gyros presented a problem. Mechanical gyros were not really practical due to the spin up times and flight characteristics (ie they took to long to spin up, and didn't take kindly to rapid shifts in trajectory), so ARPA developed the laser gyro. This meant that the gyros and associated guidance system was available essentially instantaneously permitting a very rapid launch which was a major design goal.

HiBEX was not designed to use the MSR, but instead used another radar called the HArd Point Demonstration Array Radar (HAPDAR).

All up, 7 missiles were tested at White Sands Missile Range during 1965.
"

Anonymous said...

Milo, again, I don't think I'm making myself clear; when you launch an interception mission, you do so with smaller craft loaded with missiles and other kinetics (and maybe one or two laser-heavy craft to counter any of theirs); I was envisioning the attacking force being more naval-type while the intercepting force being more Air Force-type. I think that you are imagining both sides launching battle constellations consisting of identical types, instead of one side being optimized for bombarment and the otherside being optimized for a single-pass-type attack; each squardron launched for interception would make a maxium attack and then loop back to Earth after several weeks or months; the purpose of each attack would be to weaken the attackers to the point where it can't successfully break through the permanent orbital defense forces. I gotta work on my word-picture painting skills :(

Ferrell

Tony said...

Ferrell reiterates a very important point: for the defender of a body, he as to be either sure a deep space interception is going to be 100% successful or he has to leave a reserve in the orbitals to make sure any "leakers" are dealt with. Since he cant be sure of the former, he must do the latter. A compromise position is to design the intercept so that all available forces are used in a concentrated fashion, but all of them, or at least a good portion, never get out of range of the orbitals of the defended body.

In any event, an interception is a pure attrition tactical engagement. The whole point is to destroy as many incoming forces as possible. Therefore, as Ferrell points out, the intercepting forces will be armed with whatever they think gives them the best chance against the incoming enemy forces in realtively flat space, not what will work against the enemy's planet, or necessarily what will work in low and medium altitude orbits.

Rick said...

Basically it is better to fight the wolf at the threshold rather than by the hearth.

Byron said...

While reading on something unrelated, I stumbled onto various documents on space strategy. After reading the Air Force paper on the subject, I decided to look at it as it relates to our views.
My commentary is largely on the chapter on space power theory from the space primer. Read the chapter first.

Early thinkers on space forces considered them simply “high-flying air forces.” For example,
U.S. Air Force space doctrine was first established merely by replacing the word “air” with the coinage “aerospace” in the literature.

This is far from true in most science fiction. We take "sea" and change it to "space" instead. That's a trap that's easy to fall into, as we've seen.

One thing that seems to be missing from the document is the exact means of applying it's tennants. (For those who are too lazy to read it, it basically says that control of space will be the defining characteristic of the doctrine). The problem is that space is very easy to deny, and very hard to command, if we define command as Corbett does: it does not mean that the enemy cannot act, only that it cannot seriously interfere with one’s actions.
The problem is that, as we all know, a Scud-class missile is more than capable of killing a sattelite. Any nation with a moderate technological base can develop a low-orbit ASAT. The most difficult part is likely to be the seeker.
The second issue is that space will not be a primary theater in any planet-based war. It simply can't be. You won't be able to prevent enemy invasion by controling space. You might make him blinder, but you can't win it, or even force a draw. Seapower can prevent the loss of wars, though it rarely wins them outright. Spacepower can't even do that.
One thing that has struck me is that a major space war between Earth-based powers is likely to resemble nuclear war in overall results. Both sides will have enough firepower to be able to destroy the enemy's spacecraft completely. However Kessler syndrome fallout will have a major impact on LEO travel for a long time to come, probably rendering it uninhabitable or at least quite hostile.
(Continued)

Byron said...

(Continued)
This would lead to some sort of defense against the missiles in question, either with beams, kinetics, or manuverability. This could be a plausible start to a space force. Another option is to move into higher orbits, where reaction times are longer, and the interceptor missile must be larger.
This would make it in all powers best interst to avoid shooting at each other's sattelites with ground-based kinetics. They would either not engage in space warfare, or find means that don't lead to LEO being filled with debris. Option for this include EMP weapons, blinding lasers, and electronic warfare.
Another possibility is that both sides refrain from shooting at space from the ground, and instead position forces (manned or unmanned) in orbit that are tasked with intercepting and disabling opposing sattelites and space forces. Maybe international law only allows combat by deorbiting the opponent's sattelites, but you have to avoid being caught at close range doing so.
This could lead to a two-stage development of space forces, based uppon the operational theater. The first space forces are developed for orbital conflict as part of earth-based conflict. Later, interplanetary conflicts cause alternate development, as space strategy can be characterized under one of two phases: as a supporting role in planetary warfare, or as the vital theater in interplanetary warfare.

Some other links on space strategy:
Corbett in orbit
On Space Warfare: A space power doctrine
Toward a theory of space power

Byron said...

Rick, I think my last comments just got lost to the spam filter.

Milo said...

Byron:

"Seapower can prevent the loss of wars, though it rarely wins them outright. Spacepower can't even do that."

Not if all the combatants are on the same planet. If you have interplanetary trips to worry about, then the naval analogy becomes more reasonable. You can't invade Mars unless you can get to Mars.

I agree that there is essentially no reason to use space as a theater for Earth-to-Earth wars.

Rick said...

I've let everything out (except spam) - I hope I didn't accidentally elf a real comment.

There's a fundamental difference between all 'serious' discussion of space strategy and most space strategy in SF, namely that the former is concerned purely with earthly rivalries spilling over into space. Whereas in SF we are (usually) dealing with space-centric rivalries between powers not based on the same planet.

Milo said...

Rick:

"There's a fundamental difference between all 'serious' discussion of space strategy and most space strategy in SF, namely that the former is concerned purely with earthly rivalries spilling over into space. Whereas in SF we are (usually) dealing with space-centric rivalries between powers not based on the same planet."

Discussing strategy between space-centric rivalries between powers not based on the same planet is perfectly reasonable... provided you have powers not based on the same planet!

Even with optimistic tech assumptions, building colonies on other planets and developing them to the point where they are political powers in their own right is going to take some time. At least a few centuries. So current political theorists can be forgiven for not particularly worrying about such powers yet.

Like I said in one of the later threads: before we blow up our colonies, we first have to build them.

Thucydides said...

Early thinkers on space forces considered them simply “high-flying air forces.” For example,
U.S. Air Force space doctrine was first established merely by replacing the word “air” with the coinage “aerospace” in the literature.
This is far from true in most science fiction. We take "sea" and change it to "space" instead. That's a trap that's easy to fall into, as we've seen.


Substitute powers a continent apart in the age of sail and I think we are a bit closer to the mark. The sheer distance and amount of time it takes to get anywhere is far closer to age of sail naval warfare than any other historical analogy I can think of. Even Cold War combat in space would have been spread out over prolonged periods of time as spacecraft with limited delta V changed orbits to match non cooperative targets, and potentially ships could have been sent into cis lunar space to develop some sort of strategic depth (it would take at least three days to reach you).

The only weapon that would resemble an interceptor aircraft would be Excalibur X ray lasers popping up out of the ocean (based on refurbished SLBM subs), the High Frontier "Space Cruiser" would be the manned analogue to a fighter, even able to dip into the atmosphere to make plane change manouevres (although I believe the purpose of the Space Cruiser was to inspect unknown spacecraft in orbit).

It is true that in the current environment, space is not a decisive theater of operation, but rather a supporting theater (much in the way early WWI aircraft could influence battles by taking photographs or using a signal lamp to attempt to send corrections to artillery batteries). Even weapons based in orbit like "Thor" (AKA Rods from God) are more of a tactical platform than anything else.

Geoffrey S H said...

Modern Space Warfare discussion concerns disrupting satellites electronically, with some advanced studies looking at beam sats that can strike from more orbital positions than a kinetic sat. Some analysts that I have read have made some rather odd references to "cruiser" microsats that seemingly can change orbit at will (and "patrol", whatever that means in space), but nevertheless, there is some realism in planning developing over the concept.

Nevertheless, for now, its probably best to assume that "all space warfare is electronic warfare"- i.e.: one author compares denying the flow of information between comm-sats as a form of blockade.

Byron said...

Milo:
Not if all the combatants are on the same planet. If you have interplanetary trips to worry about, then the naval analogy becomes more reasonable.
That was entirely my intent.

Thucydides:
Substitute powers a continent apart in the age of sail and I think we are a bit closer to the mark.
Not if they're all on the same planet.
It is true that in the current environment, space is not a decisive theater of operation, but rather a supporting theater (much in the way early WWI aircraft could influence battles by taking photographs or using a signal lamp to attempt to send corrections to artillery batteries).
I think a better analogy is the Middle East in WWII. It's important, but not really vital, to winning.

Thucydides said...

Byron

With current state of the art, it still takes a long time to get around in space. The US had ASATs capable of launching off an F-15 back in the 1980's, but Soviet era ASATs required the vehicle to achieve orbit, manouevre to match the orbit of the target, move up to the target then detonate. Under the best circumstances it seemed the USSR's ASAT needed a minimum of two orbits to match positions with the target (and that does not count time waiting on the launch pad for the target to line up).

Except for pop up attacks from highly mobile platforms, space combat will take a considerable amount of time unless the platform has some sort of "torch" level propulsion system.

Tony said...

Byron:

"
One thing that has struck me is that a major space war between Earth-based powers is likely to resemble nuclear war in overall results. Both sides will have enough firepower to be able to destroy the enemy's spacecraft completely. However Kessler syndrome fallout will have a major impact on LEO travel for a long time to come, probably rendering it uninhabitable or at least quite hostile."


Actually, the resemblance to nuclear warfare would be more in the realm of deterrence strategy than anything else. The calculus would be about when is the right time to start going after enemy space assets, because once you start attacking his spacecraft, he starts attacking yours. Colateral damage is going to be a (very) secondary consideration when the outcome of the war is an issue.

Another interesting question would be the fate of community assets. GPS, for example, may be a wholly owned US system for legal purposes, but everybody uses it to their advantage. The Selective Availability capability still exists, but putting it back in effect just gives the enemy an incentive to attack GPS satellites. If everyone can use it, then it's a neutral feature of the environment. If only certain parties can use it, why should competitors that aren't in the club allow it to exist?

So in future wars where space assets exist for both sides, we might expect to see a lot of maneuvering of ASAT assets into position, but aversion to first use. We might also see certain community assets being left in capability specific safe havens, because nobody wants to forego benefits they accrue from such systems, simply to deny those benefits to others.

Byron said...

Tony:
That's a lot of what I meant. People will be reluctant to do so, as everybody dies. Also, don't neglect the debris problem. That would make other nations exert pressure to keep the war under control.

Tony said...

Byron:

"Also, don't neglect the debris problem. That would make other nations exert pressure to keep the war under control."

To finish first, first you must finish. A competent command authority won't give the whole game away worrying about what the kibbitzers are kvetching about.

Thucydides said...

Here is the time to get from point a to b using minimum energy orbits in the Earth-Moon system. Obviously you can go faster with more energy, but it is illuminating to see how long it could take using current tech (believe it or not, a friend was showing me a site devoted to Mobile Suit Gundam and this table was in one of the pages http://www.dyarstraights.com/msgundam/lagrange.html):

Hohmann Orbit Transit Times within the Earth Sphere
Transit Time Trajectory
9.6 hours (0.4 days) From the Moon to or from L1
12 hours (½ day) From the Moon to or from L2
14.4 hours (0.6 days) From Side to Side within L4 or L5 (Lagrange halo orbit)
21.6 hours (0.9 days) From L1 to or from L2
60 hours (2½ days) From L1 to or from the Earth, L4 or L5 (equilateral points)
72 hours (3 days) From the Moon to or from the Earth, L4 or L5 (equilateral points)
72 hours (3 days) From the Earth to or from the Moon, L3, L4 or L5 (lunar orbit)
120 hours (5 days) From L3 to or from L4 to or from L5 (120° around lunar orbit)
132 hours (5½ days) From L1 to or from L3
144 hours (6 days) From the Moon to or from L3 (180° around lunar orbit)
156 hours (6½ days) From L2 to or from L3

Geoffrey S H said...

Any further ideas on what different types of kinetics spacecraft would look like?
i was diverting some thought to this ealier;

Turreted missiles craft.
Craft that are joint kinetic/laser.
Craft with missiles trapped on outside the main hull.

Other? there are some useful concepts one guy did that I found some time ago- I'll post them tomorrow when I find them. They are very space-opery... but have some interesting ideas nonetheless.

Tony said...

Think of about just about any way missiles have been deployed on naval vessels, and you could probably find an application in space for the same. It all depends on your technical assumptions. If missiles needed to be serviced by the launching vessel, they would be launched off of rails or out of tubes. If they have no servicing requirements, they would just be mounted in boxes on the outside of the hull. If the missiles need to be pointed in the direction they are fired, you either point the ship or mount the boxed missiles on two-axis turntable mounts.

Geoffrey S H said...

I usually imagine them held inside a simple whipple shield to protect against space phenomena such as micrometiorites, and then either shoot them out of turrets so as to provide a little more punch, chuck them out of a hatch if large number need to be fired at once, or simply split the containers all open with small charges and fire all the missiles at once if it is required. Therefore you have an all-in one system with (hopefully) minimum mass penalties, that you can tailor to what ever you require. As to the diagrams I talked about, I have finally found them.

http://www.google.co.uk/imgres?imgurl=http://www.alternatehistory.com/discussion/attachment.php%3Fattachmentid%3D125440%26d%3D1293923939&imgrefurl=http://www.alternatehistory.com/discussion/showthread.php%3Fp%3D3980017&usg=__EJ0msxxbbbycC-uULcHYG0wW7gw=&h=326&w=613&sz=16&hl=en&start=16&zoom=1&tbnid=WB6RyXNMpyccvM:&tbnh=87&tbnw=163&ei=mbSxTZb3FMOi8QPp0ZWWDA&prev=/search%3Fq%3Dmartian%2Bwarship%26um%3D1%26hl%3Den%26sa%3DX%26biw%3D976%26bih%3D697%26tbm%3Disch&um=1&itbs=1&iact=rc&dur=359&page=2&ndsp=18&ved=1t:429,r:9,s:16&tx=100&ty=61

http://www.alternatehistory.com/discussion/search.php?searchid=6306973

It take alittle browsing, but they are all easy to find.

Rick said...

Discussing strategy between space-centric rivalries between powers not based on the same planet is perfectly reasonable... provided you have powers not based on the same planet!

Oh, I wasn't dissing either approach - as you say, they are appropriate to different contexts. One of which does not now exist, and probably won't for at least a few hundred years.

Tony said...

Milo:

"Multiple waves is probably less efficient than sending everything at once (Lanchester's law), unless you have some sort of strategy to justify it (I don't see one)."

Lanchestrian analysis presumes that all of both arrays are equally accessible to any individual in the opposition. It also presumes that all targets stay in range throughout the enegagement. A single pass on opposing trajectories for large forces may invlaidate the first constraint, and will almost certainly invalidate the second. You intercept in waves to elongate the time of engagement.

Milo said...

But what is the point of elongating the time of the engagement? That's only useful if your enemy has some resource that is expended according to the total amount of time it's used, regardless of whether it's being used intensively or just lightly. (For example, a shield mechanism that costs a certain amount of energy per second it's active regardless of how many shots it's actually defending against. Or, more realistically, the alertness of crew members...) Otherwise, elongating the engagement just gives the enemy more time to shoot you.

Geoffrey S H said...

Whoopsie! Second link didn't work.

Here's a better one- to find more posts by him, just click on "AngryScotsman1989"'s name and follow the instructions.

http://www.alternatehistory.com/discussion/showthread.php?p=4331487#post4331487

As regards Avatar, i just watched it for the human tech in general. The bit where the spaceplane lands on what could be a newer version of a boeing landing wheel looked So much better than any attempt at futuristic landing gear!

Scott said...

I have assumed that laser emitters will look a lot like a gumdrop or telescope (basically a scaled-up version of whatever they're calling the flying laser on a 747).

Railguns would be mounted on something that looks like a WW2 ball turret, or maybe a little more like the remote turrets on a B29. They'd be 'streamlined' because of the whipple shielding and for active-sensor stealth, and may not even have the barrels protruding.

Point-defense missiles, like the HiBEX, would be in 'vertical-launch' cells, but would cold-launch to avoid frying the hull.

Long-ranged 'torpedoes' would probably be in the equivalent of torpedo tubes, using coilguns or gas guns for initial acceleration.

Since you can only carry a few 'long lances', those would be inside the ship where they could be maintained. The PD missiles would probably be all-up rounds, ignored until they were needed.

Raymond said...

Scott:

Mostly agree, but a) I think railguns' barrels would protrude, just because of their length, and b) I'd actually envision long lances on hardpoints, possibly in a weapons bay (for maintenance), since launching tubes using either coilguns or gas guns would add substantial mass penalties, and you'd have to use additional propellant to correct for the momentum of launch. Better to add a smaller amount of transverse motion, much like current missiles fired from aircraft.

Anonymous said...

Milo said:"But what is the point of elongating the time of the engagement? That's only useful if your enemy has some resource that is expended according to the total amount of time it's used, regardless of whether it's being used intensively or just lightly. (For example, a shield mechanism that costs a certain amount of energy per second it's active regardless of how many shots it's actually defending against. Or, more realistically, the alertness of crew members...) Otherwise, elongating the engagement just gives the enemy more time to shoot you."

Yes, that expended quantity would be missiles, dumb-rounds, rockets and manuvering fuel that the attacking ships would have to use every time a new wave of interceptors attacks them. By the time the attacking ships reach their target, they should not have enough defensive weapons to counter the on-orbit defense forces or be able to get their offensive weapons through the on-orbit defenses. Additionally, any attackers mission or hard killed reduces the overall effectiveness of the attackers. Multi-wave interceptions always favor the defender, because each wave of interceptors always attacks at full streigth, while the attacking force must counter each wave with only what they have on-hand, which decreases at each engagement with the interceptors. The longer each induvidual engagement, the more resources expended by the attacking force, so each succesive wave of interceptors can be more effective. The whole point of multi-wave interceptors is to weaken the attackers to the point where they cannot successfully complete their mission. If they get turned into junk during of of the interceptions, so much the better.

Ferrell

Rick said...

So far as I can see, a single wave is most effective against a laser-type defense, so long as you're dealing with a single target, or at least a single defense envelope.

If you're sending kinetics against multiple targets, it is a whole 'nother matter. For example, destroying one laserstar in a constellation might be enough setback that the entire constellation aborts, saving you from expending the rest of your kinetics.

A kinetics vs kinetics battle is also a different matter, and 'waves' might be entirely irrelevant. A bunch of kinetics cancel each other out, whether all at once or sequentially, and whoever has some left over at the end has the advantage.

Anonymous said...

Rick said:"So far as I can see, a single wave is most effective against a laser-type defense, so long as you're dealing with a single target, or at least a single defense envelope."

True, if you are using electric-driven lasers, but if you are using chemical lasers, not so much.

Ok, if attacker-X needs y amount of kinetics/chem-laser fuel to defeat the orbital defenses, then each squadron of interceptors launched against attacker-X forces them to expend some amount of kinetics/chem-laser fuel (bombardment munitions and electric-lasers are uneffected unless battle-damaged); each wave of interception can use their total weapons-load, while attacker-X needs to retain some for future interceptions and must have amount y to defeat the orbital defenses; if attacker-X stores of kinetics/chem-laser fuel falls below amount y, the yes, they abort. (I see electric-driven lasers to be 'main' weapons while chem-lasers being secondary or even tertiary)

The bottom line is that whether to send one wave or several, depends on several fators; dominate mix of weapons, the number of interceptors on-hand, ability to intercept far enough away to even be able to send multiple waves, and what do the defenders need in the way of reserves? I think that there will be broad guidelines for battle doctrine, but each instance will have unique details and must be handled on a case-by-case basis.

Obviously, when it comes time for space intercepts, a whole constellation of military commanders' will have already discussed this in minute detail.

Ferrell

Geoffrey S H said...

"A kinetics vs kinetics battle is also a different matter, and 'waves' might be entirely irrelevant. A bunch of kinetics cancel each other out, whether all at once or sequentially, and whoever has some left over at the end has the advantage."

This intrigued me- might less kinetics by one side perhaps enable them to manouvre them and direct them with greater ease and efficiency? Less junk on the radar and all that- and thus a clearer battlespace for a time for the one that uses his kinetics sparsley?

Probably a flawed idea....

Thucydides said...

Sorry, God favours the biggest battalions.

Since the pK of any weapon will always be less than 1.0 (100%) then you will always need to be able to fire at least two interceptors or rounds (or bursts of laser energy etc.) for every attacker.

As Tony is fond of pointing out, there will be limits to the amount of sensors and other equipment that can be produced, so at some point the side with the greatest industrial capability will overwhelm the other side. For the attacker, there are a few work arounds, for example filling the sky with dumb rocks on the attack trajectory (delivering dumb rocks with the same busses that the KKVs are carried on).

Laserstars using electric energy from the ship's reactor theoretically has the ability to deal out hundreds of shots at a time are the other work around, and if a laserstar capable of (say) 100 shots costs less than the same number of KKVs, then the advantage will tip to the laserstar.

Milo said...

I do not think any kind of weapon, laser, kinetic, or more exotic, will qualify as equipment that is more effectively defeated in waves. I will not be firing a constant number of shots per wave, I will be firing a number of shots proportional to the number of enemies I need to kill. (Mostly - larger forces may actually require slightly-more-than-proportional ammunition to take out, because of Lanchesterian benefits to their point defense.) Also remember that it is often posible, an advantageous, to disable a weapon platform before it has expended its full ammunition supply. "Let the enemy shoot at us as much as they want until they run out of bullets" does not factor very highly in most militaries' strategic doctrine.

A video game type smartbomb, the kind where you simply press a button to kill all enemies on the screen, would justify it. In that case it is smarter to attack in small waves so the enemy can't wipe out your entire force with one smartbomb. But those have no basis in reality.

Another possibility is if you have heavily missile-dominant environment, where a single missile has a very good chance of successfully destroying any given ship. In this case, even a single ship can wipe out a much larger fleet - it'll die, of course, but not before launching numerous fire-and-forget missiles that will keep homing in on their target after their launcher is blown to smithereens by the fleet's combined firepower. This has no bearing on interplanetary intercept missiles, though...



Geoffrey S H:

In space, even "nearby" objects are a fair distance apart. Whatever clutter problems still persist would be more readily dealt with by installing an IFF system (and consequently ignoring any sensor blips that identify as friendly) than by using smaller forces.

A spacecraft is not going to simply crash into another spacecraft unless it was deliberately guided into doing so (if only due to a targetting malfunction).

Tony said...

Milo:

"But what is the point of elongating the time of the engagement?"

Elongating the time of the engagement, presuming you don't run out of bullets at some point during the engagement:

1. Gives you more shots at the enemy, and

2. Gives you more time to do battle damage assessment and reconcentrate on "leakers".

So what if the enemy gets more shots at you? If you're the defender, it's the amount of time you get to shoot and observe that's important, not the amount of time the enemy gets to shoot and observe you. You only have one chance, and you have to make the most of it.

Milo said...

Tony:

"1. Gives you more shots at the enemy"

Wrong. The number of shots you get is (roughly speaking) the duration of the engagement multiplied with the number of ships you have in the engagement.

If you send your attack in multiple waves, then the engagement as a whole will take longer, but any single ship will only spend a fraction the engagement within firing range of the enemy. In fact, any given ship's time spent near the enemy will be roughly the same, whether those ships all attack at once or separately. (But if they attack at once, then they'll last a little longer because the enemy will need to spend time blowing up their friends before turning guns on them.)


"If you're the defender,"

You are the defender on an operational scale, but on a tactical level you are the attacker. We're talking about "intercepts", which are about "defending" yourself by preemptively counterattacking your attackers. The intercept fleet is trying to actively destroy the invasion fleet, while the invasion fleet is not necessary interested in destroying the intercept fleet (although they will probably have to do so anyway), only in surviving to reach the planet they're trying to invade.

Rick said...

Elongating the time of the engagement, presuming you don't run out of bullets at some point during the engagement:

1. Gives you more shots at the enemy, and

2. Gives you more time to do battle damage assessment and reconcentrate on "leakers".


I agree with Milo that #1, at least, seems to favor the tactical defender. The attacker wants to minimize the number of shots the other side gets, and has already implicitly fired all their shots, the size of the attack wave.

But all of this also depends on the weapons of each side. Lasers have a maximum 'rate of fire,' time-averaged zapping power, but, if powered by a reactor (or solar array) an effectively unlimited ammo supply.

Kinetics have, presumably, a finite magazine supply, but you may be able to 'flush the pods' and launch anything up to your full supply effectively similtaneously.

Scott said...

But all of this also depends on the weapons of each side. Lasers have a maximum 'rate of fire,' time-averaged zapping power, but, if powered by a reactor (or solar array) an effectively unlimited ammo supply.

Depends on their cooling capacity. If your lasers can generate heat faster than you can get rid of it, then your laser magazine capacity is determined by your cooling system capacity, not your laser-fuel tank capacity.

I still think that you'd see 'torpedoes' in some kind of gun mechanism, since it's easier to maintain something in atmosphere. It will probably be a really low-powered gas gun, though, with maybe 25-50m/s delta-vee (or less) applied to the torp. In other words, about as much oomph as a modern torpedo tube on a sub.

Thucydides said...

The attacker will be facing a layered defense, so the argument will be repeated multiple times (depending on how may layers the defender can afford to build and maintain).

You will want to open the engagement at the longest possible range both to get the advantages of time and to upset the enemy's calculations. If they take evasive manouevres they now have less delta V for the main engagement. At some tech levels, they might actually have gone off course and not be able to get back on an optimum trajectory (splitting the fleet apart like using fireships against the Spanish Armada).

Deeper layers will (if everything is working correctly) have to deal with fewer and fewer targets until the whittled down incoming force is facing ASATs, ABMs and fighting mirrors from ground based lasers.

The flip side is that each attacking unit is either cheap enough so that you can overwhelm the defenders at each level with sheer numbers, or each attacker alone can deliver devastating damage so only one needs to get through.

Milo said...

Scott:

"It will probably be a really low-powered gas gun, though, with maybe 25-50m/s delta-vee (or less) applied to the torp. In other words, about as much oomph as a modern torpedo tube on a sub."

50 m/s is useless in space.

A simply chemical rocket boost phase on the missile can give you far more than 50 m/s. People won't be using missile-launcher guns at all unless they can produce higher speeds with greater efficiency than the missile's own rocket engine can.

Also, you need enough speed to actually reach your target. In space, I would consider any speed lower than 1 km/s to be barely worth mentioning. (Or even 2.893 km/s, that being the speed of 1 Rick.)

Rick said...

Scott -

If your lasers can generate heat faster than you can get rid of it, then your laser magazine capacity is determined by your cooling system capacity, not your laser-fuel tank capacity.

This will mostly work out the same way - your sustained zap intensity is sset to whatever your cooling can handle, but you can pretty much zap at that intensity as long as you can hold the trigger.

In the case of kinetics in 'torpedo tubes' just pump them out and let them drift until you've deployed your intended salvo - then they can all light up together and be on their way.

This is predicated on fighting at long range, but so long as one side is arriving from deep space, a long range fight seems likely.

Thucydides said...

Even in orbital combat, opening the range will be a better tactic. You will have the widest possible horizon for sensors and the longest dwell time for your weapons and sensors.

Moving in a high orbit also means it takes less delta V to change orbit, and potentially gives you much more room to manouevre (you can boost to GEO and beyond or low orbit if you have a powerful enough engine). A platform in LEO really only has one direction to go (unless you count diving into the atmosphere).

A constellation will probably be divided between platforms in LEO and in the "high guard" position in high orbit to provide a balance between coverage and speed of reaction, the wealth of sensors will provide 3D positional information of every object and potential target under observation.

Tony said...

Milo:

"Wrong..."

I apologize for not making this clear: I didn't mean more shots in an absolute sense, but more shots in the sense of an evolving tactical balance. If everybody merges with the incoming eney formation at the same time, weapons have to be evenly distributed, and any bit of luck on the part of the enemy can't be countered. With two or three (more?) equal waves, there's less chance per wave of getting a kill, but, presuming some kills are recorded with each wave, then each wave get's stronger WRT the enemy force, and has more shots per target.

You are the defender on an operational scale, but on a tactical level you are the attacker...:

And? I'll use the tactics that give me the best chance to reduce the attacker to the smallest possible number before they reach my final line of defense in the orbitals.

Anonymous said...

Milo said:"50 m/s is useless in space."

Relitive to what? The ship that fired them, or the ship that they are targeting? 50 m/s relitive to the firing ship may be 20+ Km/s relitive to the targeted ship. Remember, in space, everything is moving relitive to each other.

Ferrell

Rick said...

Agreed. I took the 50 m/s as simply a kick to get the kinetic clear of the launching vehicle.

Milo said...

Tony:

"each wave get's stronger WRT the enemy force"

Yes, but by a smaller margin than the strength advantage you would get if you didn't bother with waves and send all your forces at once.



Ferrell:

"50 m/s relative to the firing ship may be 20+ km/s relative to the targeted ship."

So? If 50 m/s relative to the firing ship is 20 km/s relative to the targeted ship, then 0 m/s relative to the firing ship is 19.95 km/s relative to the targeted ship. So your shot does 0.5% more damage. Big deal.



Rick:

"I took the 50 m/s as simply a kick to get the kinetic clear of the launching vehicle."

If that is my objective, then I would use whatever I think is the most robust and reliable mechanism I can make (even while coping with combat conditions), regardless of how weak it is. A simple spring action could probably give you a couple of m/s, if that's enough.

Thucydides said...

50m/s is the speed achieved by an arrow from a bow with a fairly low draw weight. From a practical POV I want to have KKVs or busses clearing my platform at a much higher rate of speed, especially if there is risk of being attacked before the weapons clear the ship.

If there is no intention of reusing the launch tube/box or the launch platform (depending on your design philosophy and other factors like mass and cost) you might just hot launch the things and accept the effects on your ship. Since I would want on board sensors to remain clear to provide target data I would lean towards some sort of cold launch system (gas gun, captive piston, coil gun, catapult, two big crewmen heaving it over the side etc.), with the booster igniting well clear of the platform.

Tony said...

Milo:

"Yes, but by a smaller margin than the strength advantage you would get if you didn't bother with waves and send all your forces at once."

That only matters if you can get every element in the enemy array in a single pass. If you can't, how much you overwhelm him with a single pass is useless to you for practical purposes. Lengthening the engagement duration by stretching out your forces over space is a tactic designed to reduce the likelihood of the inevitable hard and/or lucky enemy elements getting through.

Rick said...

50m/s is the speed achieved by an arrow from a bow with a fairly low draw weight. From a practical POV I want to have KKVs or busses clearing my platform at a much higher rate of speed, especially if there is risk of being attacked before the weapons clear the ship.

The likely time scale of a space engagement is such that deployment of the weapons can be very unhurried - I suspect that 50 m/s would be at the high end of separation boot speed.

Tony said...

Rick:

"The likely time scale of a space engagement is such that deployment of the weapons can be very unhurried - I suspect that 50 m/s would be at the high end of separation boot speed."

Actually, the magnitude of the separation impulse would probably be governed by the amount of time allowable for separation from the launching ship before the missile needs to start maneuvering. Say you need the missile to be 500 m from the launching ship before it starts maneuvering, and nothing tactically significant is going to happen if it takes ten seconds to achieve that separation -- then 50 m/sec is acceptable. If you have the same standoff requirement, but you want the missile to start maneuvering within five seconds? Then your separation impulse beter generate a 100 m/sec delta-v.

WRT VLS style launching, you probably don't want to do that, because it uses up propellant to adjust the weapon's course before it begins effective maneuvering against the target. A trainable launcher gets the weapon going on the right vector without using propellant to do it.

Geoffrey S H said...

@Milo:

I meant in terms of guiding missile salvos towards each other, not in confusing forces with each other- more computing power diverted to a smaller salvo to give them an extra advantage telemetry wise.

The massive effective ranges involved would allow several salvos to be launched... until th commander decided that he had bled the enemy alpha strike enough and send his own mini-alpha back in the confidence that he had a larger surplus of missiles to reach and penetrate the enmy pds than his opponent.

Feel free to correct me if the notion of telemtry being diverted to aid the missiles is a flawed and innacurate concept. EW is not one of my strong points. I have a better argument for salvos which would unforetunetly require alittle handwavium technology, so I won't press the point.


TBH though, I'm beginning to think, that with the nature of various weapons involved, if they are introduced at diferent times, we could see salvos and alpha strikes perhaps employed at various times in a potential future history- Tony and Milo are both right. Maybe we are all just talking past each other...
Food for a potential astral-military (future) history...

Milo said...

Geoffrey S H:

"Feel free to correct me if the notion of telemtry being diverted to aid the missiles is a flawed and innacurate concept."

I think that computing power is sufficiently cheap compared to basically everything else in space, and compared to the amount that you actually need, that you can basically be assumed to have as much as you need. This is especially true of ground control computing power (and onboard computing power will scale with the number of ships you have).

Even if your computations lag a little, then will that really be noticeable over the other delays in the system like lightspeed lag and the time it takes for a missile to reach its target? Absolute split-second decisions aren't necessary here.

Anonymous said...

If your engagement only takes 200 seconds and you know how many days it'll be until you reach that point, then you can spend the day before the engagement setting up the 'battle space' like a big chess game. Then get a good night's sleep, get up early and eat pancakes for breakfast, before you spend 2 1/2 minutes of shear terror trying to hit the ememy and not get killed. That deployment velocity of 50 m/s doesn't sound too bad now...

Ferrell

Thucydides said...

The real trick here is to overwhelm whatever defense system the enemy has put in place. You can use sheer volume of fire to saturate any defense system, the fastest practical weapons to cut down the available engagement time, penetration aids to confuse enemy sensors and fire control systems or armoured KKVs.

Like layered defense, there may be layered attack as well, using waves of weapons with different properties to confuse the defender and invalidate some or all of the weapons systems. This is limited to what the attacker can actually produce with the available resources and what they expect the defenders to have.

KraKon said...

Dumping vs waves:

Dumping missiles overboard for a firing rate of infinity (2000 missiles divided by zero time for deployment) allows you to easily overwhelm anything. Against laser armed opponents, this is the tactic to use, you maximize the chances of all of your missiles hitting, and when they do, they'll destroy the opponents. Remaining craft will be just lucky (fleet warfare is supposed to be made that way-you have onboard enough force to destroy the enemy several times over) to survive, and can be picked off with the remaining stock of weapons, which is now concentrated to much fewer targets. This is viable with a setting where chemical rockets reign supreme. There is absolutely no reason to refrain from firing them other than saving a few to pick off 'leakers'. After all, your enemy has an infinite-ammo laser defense system, better overwhelm early then allow for your missiles to be picked off as they arrive.

There is a case where you do use waves-when you can't do otherwise. One example is laser-powered thermal rockets. Their firing rate is limited by how many lasers you have, and how powerful they are. Sending in waves, with all the missiles meeting up at the enemy for a single overwhelming number of missiles directed at a few targets, is the best option. This way you have reduced the number of lasers available to the enemy, meaning his next retaliation wave is going be sparser and further spaced apart.

Here's an example. I have 6 ships, and 18 lasers available. I can fire 35 missiles per wave. Total number of missiles I can direct at one of the opponent's ships? 630. If 300 missiles are enough to take out a single ship, I have removed two from the opponent's force EVEN IF all their buddies gang up to save them.
Next it is the opponent's turn. He can only fire 420 missiles at me. This only takes out one of my ships. Next turn, I destroy only one of his. In retaliation, he can only send out 315 missiles. If I manage to save one of my ships from destruction then, I win. He cannot send out eneough missiles to remove one of my ships, I can always pick of his ships one by one with overwhelming force.

Rick said...

Ferrell -

then you can spend the day before the engagement setting up the 'battle space' like a big chess game. Then get a good night's sleep

This is pretty much my thinking, at least so long as you're fighting in open space. (Low orbit or very cluttered space is different.)

A corollary is that our image of crews jumping out of bunks or throwing down poker hands to hustle to battle stations when the klaxon sounds has no place in space warfare.

More like "Attention, all hands! We anticipate an engagement within the next 72 hours. Readiness countdown will commence at 0800 hours tomorrow ..."

(Onboard emergencies are another matter. All space crews, military or civil, will react quickly to "Fire in the spacecraft!")


KraKon -

It's a slow mind morning, and I'm afraid your example for laser-thermal missile waves completely eludes me. I'm not sure how those numbers are being added up. (Why 35 missiles per wave, 630 total, etc.?)

Milo said...

KraKon:

"Dumping missiles overboard for a firing rate of infinity (2000 missiles divided by zero time for deployment) allows you to easily overwhelm anything."

The only disadvantage of dumping is that it may be a waste of ammo if the amount of missiles you carry is overkill for the opposition you're facing. If you think a few missiles will suffice to finish off the enemy, then it makes sense to just launch that, and only spend more missiles if you find out you were wrong.

In space, though, there's no stealth, so the only uncertainty in an enemy's strength comes from doubt on the exact capabilities of a particular ship class. Even if you don't have accurate espionage information, you just be able to make a reasonable guess based on the ship's mass and shape. So I'd expect you should always be capable of a reasonable order-of-magnitude estimate on an enemy task force's strength (and thus how many missiles it'll take to kill).



Rick:

Knowing humans, I say that a battle being known about days in advance and clearly counted down to in no way prevents startled soldiers from throwing down poker hands and hustling to battle stations when the klaxon finally sounds.

Raymond said...

Krakon:

- Your exhaust velocity estimate for nuke-thermal using an iceball as propellant is somewhat flawed, since the usual ~9 km/s Ve is based on hydrogen, not water. When comparing exhaust velocity of various gases, Ve varies by sqrt(temperature/molecular mass). Given the same temperature (which is usually a fundamental limitation of nuke-thermal) and a gas nine times more massive, the exhaust will be a third the velocity. So you'd end up with about 3 km/s using water.

- In the same vein, I'm not sure where you're getting your 40 km/s Ve for your laser-thermal missiles...

Anonymous said...

I've been thinking about this and I've come to the conclusion that there are only three scenarios for space warfare:
1) Orbital; messy, lots of stuff to avoid, and only short-range laser or PB weapons and few kinetics to try to keep the shrapnal down.
2) Head-on Intercepts; two, or more, groups of ships passing by each other at interplanetary velocities. Combat dominated by kinetics during closing (approching) and lasers and PB's during the opening (retreating) phase.
3) Converging Trajectories; Least likely to happen; two, or more, groups of ships leave the same volume of space at the same time, heading for the same place. Energy weapons and high delta-V kinetics are used until either exhasted or one or both groups are so shot up that they can't continue combat.
If anyone can think of any other scenario, let me know.

Ferrell

Rick said...

Milo -

Knowing humans, I say that a battle being known about days in advance and clearly counted down to in no way prevents startled soldiers from throwing down poker hands and hustling to battle stations when the klaxon finally sounds.

LOL - quite true!

On salvo size, I agree that you probably have a fair idea of how many kinetics you need to shoot to take out an attacker.

And you damn well better launch that many, if you can, because if you underestimate, you've thrown away a bunch of kinetics and achieved nothing except some operational wear and tear from zapping with their lasers.


Ferrell -

I think there's an important borderline case between #1 and #2 - if an attack force is coming from deep space, I'd prefer to fight at the outer fringe of my orbital space, away from my civil infrastructure.

My speed relative to my planet will be low, since I'll be in a very high orbit. (Except for kinetics that I throw as fast and hard as I can.) The attacker will be slowing down from transfer speed - except for their kinetics, which they'll likewise throw hard.

Thucydides said...

As far as space logistics are concerned, I think Krakon is coming from the right place.

Water seems to be pretty abundant in the Solar System. Even the Moon turns out to be far "wetter" than anyone thought even a few years ago. If proper allowances are made to deal with the corrosive nature of superheated water in the reactor chamber then we have a readily available, low cost and easy to handle supply of remass wherever we go.

Following the prescription of Anthony Zuppero (http://www.neofuel.com/index_neofuel.html) and simply using water directly vastly simplifies things, you only need some heat to melt the water and away you go. Hydrogen, while more efficient, requires lots of infrastructure in the form of water processors, electrolysis machines, cyrogenic coolers and heavily insulated tanks, which really eats your mass budget and requires more staff to operate and maintain (and even more mass for habs and life support).

Now we still want the highest possible exhaust velocity, so it would be advantageous to use ultra high temperature reactors like "vapour core" or "Nuclear Light Bulbs", or inject water into the exhaust of a fusion reactor. The KKV's have much different needs, and will probably use conventional solid fuel rocket motors for boost (ultra high impulse engines like the Sprint ABM or HiBEX to close the range very fast) and small liquid fuel motors (or something more exotic [magitech]) for final approach to target.

KraKon said...

"The only disadvantage of dumping is that it may be a waste of ammo if the amount of missiles you carry

is overkill for the opposition you're facing. If you think a few missiles will suffice to finish off

the enemy, then it makes sense to just launch that, and only spend more missiles if you find out you

were wrong."

I was working under the assumption that a)the chemfuel missile platform will be no more than a

lightweight bus, with around 50% mass being missiles. Enemy is the same plus the juicy targets being

the laserstars b)each of these busses easily carries enough missiles to screw over the opposing target

several times.
In that case, your fleet of launchers has enough firepower to take out the enemy in one go. Doing so is

still beneficial economically as spending all your missiles to take out a laserstar still costs less

than that laserstar. If not (if we break even economically even 2000 missiles) then possible damage

(costwise) of the laserstar remaining intact will tip the balance back in the dumping-swarms-of-cheap-

missiles tactic. You might find out how many missiles you need to take out the target just by looking

at it, but shooting a small number of missiles at a single target (just enough to overwhelm it) is not

as efficient than sending a much larger wave to take out ALL targets at once (laserstars never work

alone) because the point defence is much better at taking down a small, concentrated wave than a huge

wave distributed among several targets.
This is a tactic in nature. A shark can easily chomp on a fish, and 5 fishies trying to get past 10

sharks is wasteful compared to 20000 fishies in a shoal confusing the efforts of 10 sharks.

KraKon said...

Raymond:

"- Your exhaust velocity estimate for nuke-thermal using an iceball as propellant is somewhat flawed,

since the usual ~9 km/s Ve is based on hydrogen, not water. When comparing exhaust velocity of various

gases, Ve varies by sqrt(temperature/molecular mass). Given the same temperature (which is usually a

fundamental limitation of nuke-thermal) and a gas nine times more massive, the exhaust will be a third

the velocity. So you'd end up with about 3 km/s using water.

- In the same vein, I'm not sure where you're getting your 40 km/s Ve for your laser-thermal

missiles..."

Ah. You're right for the NTR, too bad I don't know what NTRs work at temperature-wise (I mean the solid

core ones). Even with 3km/s EV, we still have 30km/s to play around with, which is still eneough for

interplanetary travel. Thrust is tripled too.

40km/s for the LTMs is actually what I get when I have to lower exhaust velocity for acceleration,

while still getting 80km/s+ end velocity. The LTMs have a hydrogen tank with 270kg of liquid hydrogen

in it. Bursts of hydrogen gas is released (it is heated by waste radiation, turning it to gas) and

blasted by two successive laser pulses, first ionizing then heating it for thrust. Since exhaust

velocity is based on their temperature, and each pulse has 40MJ in it, I can vary how much gas I

release, the exhaust velocity can be moved from 5 to 300km/s. After all, this is the same principle as

a VASMIR, with the radio heating replaced by laser heating, and it gets up to 300km/s exhaust velocity.

"If anyone can think of any other scenario, let me know."

Letting my imagination run, I can give two more.
A long highly ecliptic orbit that passes between low orbit and high orbit. It would pass at high

velocity through low orbit, just enough to drop a kinetic payload while giving the ground-based times

little time to intercept it in return.
Combat around a gas giant. Even the low orbits are high velocity, and there are no ground-based

defences or orbital clutter to worry about. Sly enemies could pass throught the upper atmosphere,

popping up from under surprised opponents travelling at higher, therefore slower orbits.

Thucydides said...

Plunging into the atmosphere of a gas giant will leave lots of detectable energy in the form of a wake and thermal energy , with the possibility of radio noise as well as the ship interacts with the planetary magnetosphere.

The surprise will be when the clever captain pulls out of the atmosphere smack into a spread of nuclear warheads and some high energy laser fire instead.

Anonymous said...

Rick:"I think there's an important borderline case between #1 and #2 - if an attack force is coming from deep space, I'd prefer to fight at the outer fringe of my orbital space, away from my civil infrastructure.

My speed relative to my planet will be low, since I'll be in a very high orbit. (Except for kinetics that I throw as fast and hard as I can.) The attacker will be slowing down from transfer speed - except for their kinetics, which they'll likewise throw hard."

Ok, 4)Modified Interception; devergent and changing relative velocities between two or more groups of combat spacecraft at the boundry of interplanetary and orbital space. It has charateristics of both orbital and deep space interception. It uses the greatest variety of weapons and tactics.

Can anyone think of anything else? Does anyone have any refinements to these scenerios?

Ferrell

KraKon said...

"Plunging into the atmosphere of a gas giant will leave lots of detectable energy in the form of a wake and thermal energy , with the possibility of radio noise as well as the ship interacts with the planetary magnetosphere.

The surprise will be when the clever captain pulls out of the atmosphere smack into a spread of nuclear warheads and some high energy laser fire instead."

Oh, I didn't mean for him to be undetected, just to orbit faster and catch up with the enemy at a favourable position. He'll be concealed against the gas giant's background, while the targets would be stark naked agaist space.

Milo said...

KraKon:

"Combat around a gas giant."

I'm still wondering how effective magsail and related propulsion methods would be in the region of a gas giant.


"there are no ground-based defences"

Not on the gas giant itself, but there will be on the gas giant's moons, which are presumably what you're fighting over. (Even if you want gas giant helium-3, then you probably need a base of operations on a moon to economically extract it.)

The large size of a gas giant's Hill sphere means that while in transit between moons you'd most likely be out of range of those defenses, though.


"or orbital clutter to worry about"

Again, maybe not now, but if people start settling there, there will be orbital clutter. Both orbiting the gas giant itself, and its various moons.

Rick said...

I'm pretty doubtful of scooping stuff up from a gas giant atmosphere - that is a LOT of frictional heating. But if it is viable, there may be a considerable amount of infrastructure in low orbit, creating significant clutter there.

KraKon said...

"I'm still wondering how effective magsail and related propulsion methods would be in the region of a gas giant."

Jupiter's magnetosphere is 14x stronger than Earths, at 4.2-14 gauss. Since there have already been proposals for magsails operating on Earth's magnetosphere, I'd think they'd likely be used with more efficiency around Jupiter. However, as efficient and neat as they may be, I think they'd still be limited to slow transits between moons, as thrust is not adapted to combat situations (worse than nuclear-electric, advantage is that you have a much smaller overhead in reactor size). I think they'd be used for orbital satellite stationkeeping, and transfer of small goods (like a truck compared to a train).

"Not on the gas giant itself, but there will be on the gas giant's moons, which are presumably what you're fighting over. (Even if you want gas giant helium-3, then you probably need a base of operations on a moon to economically extract it.)

The large size of a gas giant's Hill sphere means that while in transit between moons you'd most likely be out of range of those defenses, though."

The larger volume of space means that while it may be cluttered around the moons, you don't have to find in that clutter. What I was supposing here was diving to very near the gas giant, allowing faster orbit times. This allows a fast transfer between moons, despite being uneconomical on fuel. Actually, it might be economical. Diving from a moon's orbit to the giant (by accelerating down rather than decelerating) then using an Oberth boost maneouver as your higher velocity pushes you out of the too-tight-for-your-velocity low orbit might work.

"Again, maybe not now, but if people start settling there, there will be orbital clutter. Both orbiting the gas giant itself, and its various moons."

The low moon orbits compared to the gas giant's low orbit probably means that there will be very cluttered garage orbits around the moons, but mostly empty space between the moons and around the gas giant itself. There could very well be Earth-level clutter in orbit, if not more, but being clumped around several small moons then spread around a giant Hill sphere leads to low orbital clutter overall.

"I'm pretty doubtful of scooping stuff up from a gas giant atmosphere - that is a LOT of frictional heating. But if it is viable, there may be a considerable amount of infrastructure in low orbit, creating significant clutter there."

The upper atmosphere of gas giants is probably not dense enough to create as many problems as low orbit on Earth today, in relation to friction. Mini atmospheric ramscoops, using collected gasses as propellant, might be a solution.

In relation to clutter, again, we forget the scales involved. If there is a lot of clutter around the gas giant itself, it would be spread VERY thinly, and there are myriad orbits for it to get lost in. Even the equatorial orbit is the size of Earth from head to toe.

Remember the objective here: Interesting Combat Scenarios.

Rick said...

The upper atmosphere of gas giants is probably not dense enough to create as many problems as low orbit on Earth today, in relation to friction. Mini atmospheric ramscoops, using collected gasses as propellant, might be a solution.

If it's not dense enough to cause serious heating, is it dense enough to allow serious scooping? (Maybe it is - but I've only ever seen gas giant atmosphere scooping discussed as a Cool Idea, without many numbers attached.)

KraKon said...

"If it's not dense enough to cause serious heating, is it dense enough to allow serious scooping? (Maybe it is - but I've only ever seen gas giant atmosphere scooping discussed as a Cool Idea, without many numbers attached.)"

Let's see...
Working roughly, say we want a 1kT ship to orbit the gas giant.
Currently, the ISS loses 2km of altitude per month, or -0.77mm/s. The Jules Verne ATV did a debris avoidance maneouver for the ISS, where a deceleration of 1m/s led to an orbital altitude decrease of 1.77km over 5 minutes. 2km is therefore 1.13m/s.
The ISS masses 417289kg, so with an exhaust velocity of 4km/s, 0.34kg of propellant was expended. -0.77m/s needs therefore around 1g/s.
Using an ion thruster with an exhaust velocity of 20km/s, 0.2g/s are needed.
This amount of propellant will easily be caught from a gas giant's atmosphere. Orbiting a gas giant, the drag will also be much lower because we are both orbiting slower and the gasses are sparser.
It's only when we want to go down deeper and yet faster that drag becomes a significant problem. Propellant wouldn't be a problem.

Rick said...

Overall this sounds better than I expected - I confess not thinking of very gradual scooping.

But this last bit is confusing:

Orbiting a gas giant, the drag will also be much lower because we are both orbiting slower and the gasses are sparser.

In any case the next trick is capturing the very sparse gas piling up in the scoop, but it does not sound like an inherent deal breaker.

Thucydides said...

A different approach might be to use a Moravec rotating tether to "dip" intp the atmosphere and toss buckets of gasses into higher orbit for capture and processing.

The tether might use electrodynamic energy to maintain its orbit, or the capture of incoming "empty" buckets to provide dynamic boosting so it does not deorbit and burn up in the atmosphere. (Of course, our ideas of economics might not apply anymore in the implausible midfuture, maybe the thing is disposable and replaced whenever the need arises...).

I had always pictured ramscooping to be a very fast process, using the orbital velocity to help compress the incoming gasses (and maybe even liquify them like the USAF "LACE" (Liquid Air Cycle Engine) program in the '50's. Hypersonic waveriders with very fine length/width ratios would do the trick, along with a very advanced set of internal machinery.

KraKon said...

"In any case the next trick is capturing the very sparse gas piling up in the scoop, but it does not sound like an inherent deal breaker."

Drag is caused by slowing down the gasses you are scooping. One method to reduce much of this drag is to heat the gasses up quickly enough not to need to to decelerate them. This involves a mach 20 something electromagnetic chamber that runs a very long Lorentz-force magnetic field through it. Or again, a very long chamber with VASMIR-style radio heating. Or someother kind of thing that makes sure nothing touches nothing.

The second approach is the brute force method. Can you thruster make up for drag losses of slowing down the propellant flow. Preumable yes. Blast away! This makes you craft look several thousand m² in the face of the wind instead.

"A different approach might be to use a Moravec rotating tether to "dip" intp the atmosphere and toss buckets of gasses into higher orbit for capture and processing."
An interseting idea, that would certainly work for orbital stations. If you have more power onboard, just shine a laser or some electromagnetic heating wave onto the gas below you, it'll heat and expand into orbit and all you have to do is scoop it up. I got this from learning that the atmospheric drag on the ISS is higher on the sunlit face of the Earth because the gasses are hotter, so expand and rise.

For faster warships who dive deeper or don't have time for the rotovator to spin around, this might not be the best soltion.

"(Of course, our ideas of economics might not apply anymore in the implausible midfuture, maybe the thing is disposable and replaced whenever the need arises...)."

I think this follows a bigger is better logic. Smaller rotovator scoops are rather limited in scope (directly a result of their smaller length) and while certainly cheaper, are much less efficient than a larger rotovator scoop.

KraKon said...

"I had always pictured ramscooping to be a very fast process, using the orbital velocity to help compress the incoming gasses (and maybe even liquify them like the USAF "LACE" (Liquid Air Cycle Engine) program in the '50's"

This implies quite a bit of drag...liquifying incoming gasses, oh my! Even if the drag is within the limits of the airframe and the collector device, you're going to need a lot of power to compensate. This means large scale applications are out of the window, since power densities will be high.

Rick said...

Remember that at these high velocities, 'quite a bit of drag' = a LOT of heat load.

Thucydides said...

Ramscoops that dive into the atmosphere and liquify their incoming charge of gas will be small, but also flexible. If there is a surge of demand the company can send more ramscoops, while if demand falls they can leave them in orbit. There is also some flexibility as to when scooping takes place.

A rotating tether wil need to keep running at a steady state to minimize stress and maintain orbit. Ramping production up or down will be a much slower process than spacecraft based ramscooping.

No doubt there will be an ecology of various devices based on assessments of market demand.

Milo said...

Being able to adjust production rates is nice, but not particularly important. The gas giants are not going to run out of gas anytime soon, so the only cost of overharvesting would be from wear and tear on the scooping equipment. Other than that it's safe to just release excess gas, or use it for frivolous purposes.

Also, interplanetary transport isn't going to be very fast, so unless the gas is being harvested for use in your own moon system, there's no point in being able to adjust production faster than once per cargo barge cycle.

Thucydides said...

Adjusting production might not be important to the source, but very important for the production company. If you have a vast amount of capital sunk into a tether, you need to continue producing "x" amount of gas regardless of market conditions, otherwise your tether could become overstressed or deorbit.

In a market glut situation, the company can eat the cost for a while and gas can be dissipated into space or dumped back in the atmosphere, but a ramp in demand cannot be accommodated, leaving the company to miss out on profit opportunities. Given a tether will be a singular structure with a high capital cost, the market had better be pretty stable and large enough to support the cost of the tether in the first place.

Space based ramscoops can be thought of as wildcatters. Any individual ramscoop will cost far less than a tether, and even small groups of investors could potentially buy one to start and invest their profits into a growing fleet. Downsizing or exiting the market should also be easier; mothballing one or more scoops, selling them to other companies (or start-ups) or even scrapping them are acceptable solutions.

Obviously short term fluctuations will reflect the "local" market. A company operating out of the atmosphere of Uranus will have or want a "base" market for their 3He, perhaps filling "barges" to drop into the inner Solar System, as well as secondary markets such as local spacecraft fueling and power and industrial markets on Ariel and Miranda, which are subject to more fluctuations in demand.

Anonymous said...

Thucydides; you could use a strategic reserve to even out the ups and downs of demand.

Ferrell

Tony said...

Ferrell:

"Thucydides; you could use a strategic reserve to even out the ups and downs of demand."

Or intentionally build-in surplus plant capacity. The pretroleum industry does both.

Rick said...

Any variation on these themes would work for story/setting purposes. Trying to guess what would 'really' be appropriate for a production technology this far down the road is pretty much throwing darts while blindfolded.

Milo said...

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.

Thucydides said...

Just like oil fields in Alberta or North Dakota, an "ecology" of companies and equipment will develop. There will be the BP's and Exxon-Mobile's of space with huge majestic tethers orbiting the planet to fill their long term contracts, and there will be the lonely wildcatter wrapping 22nd century duct tape around that leaking pipe in the ramscoop, as well as everything in between.

A large ecology of service industries will also be out there, from machine shops and fabricators to farms and caterers and the old standby of the saloon and local hab of ill repute.

I personally have no means of atmosphere mining that I favour over the others (well, I'm not keen on balloons, but otherwise..), knowing or guessing the sorts of factors that could drive these sorts of decisions makes the entire setting become clearer.

Since this is a thread about space warfare, I would think that ramscoops based on waverider aerospaceplanes would be useful as a source of auxilliary ships. They need to have powerful, high thrust engines and strong, heat resistant structures to do their primary function, so would have some resistance to enemy weapons fire. They will be based in orbit around the primary, so are "central" in the theater of operations. A deorbit burn to drop towards the primary and gain energy, maybe skimming the atmosphere to change orbital plane with minimum fuel use, then a burn to put the ship in an elliptical orbit heading towards the target.

For the invader, these small gnats would be annoying and distracting, and divert time, energy and resources away from dealing with primary targets and defense systems. The big economic prize would be any tethers orbiting the primary, processing plants that refine and prepare the gasses scooped from the atmosphere and any launch mechanisms that can accelerate payloads into interplanetary orbits.

KraKon said...

"For the invader, these small gnats would be annoying and distracting, and divert time, energy and resources away from dealing with primary targets and defense systems"

If these 'gnats' are easily converted into military use, it is likely that they are going to BE the attackers. A gas giant with several moons, a few inhabited, and large atmopsheric scoops providing gas for inner planets is a setting which can probably support piratry...

"Or intentionally build-in surplus plant capacity. The pretroleum industry does both."

It is quite difficult to store large amounts of gas , especially in space. You can't use thin-walled balloons as they'll get pierced by orbital junk. You're left with liquifiying the gasses, with heavy tanking and large power supplies. I see this as costing much more than just buying the cheap gas provided by small ramscoops and reselling it to the inner planet.
This is possible as the smaller ramscoops are flexible, and don't have such a large overhead in tether and refinery costs to be able to start scooping, so price per gas unit is lower. HOWEVER, they probably can't afford the inner plabnet bound gas barges, meaning the larger companies still have a monopoly on what gas is sold.
An analogy would be buying expensive American oil, but the UK has to buy it from BP even if some rancher can set up an independant oil rig in his backyard.

jollyreaper said...

No, that's all wrong! Any atmospheric mine will be floating impossibly in the gas giant's clouds right in the band that has the right mix of pressure, atmosphere and gravity to make for a shirtsleeves environment. And don't trust the administrator, he's already cut a deal with the Imperials.

Stevo Darkly said...

I have altered the deal. Pray I don't alter it further.

Anonymous said...

jollyreaper said:"No, that's all wrong! Any atmospheric mine will be floating impossibly in the gas giant's clouds right in the band that has the right mix of pressure, atmosphere and gravity to make for a shirtsleeves environment. And don't trust the administrator, he's already cut a deal with the Imperials."

Stevo Darkly said:"I have altered the deal. Pray I don't alter it further."

I must be really tired, because this exchange brought to mind that scene being played by Yosemite Sam and Marvin Martian...

Gas pirates, Big Gas, and gas wildcatters in space. Move 'Dallas' into orbit around Jupiter and give it lasers-guns. Or 'Gunsmoke'.

Ferrell

Thucydides said...

Gas pirates, Big Gas, and gas wildcatters in space. Move 'Dallas' into orbit around Jupiter and give it lasers-guns. Or 'Gunsmoke'.

"There will be Helium"

Rick said...

"There will be Helium"

Now I feel like an idiot, because this is probably a riff on a line I should recognize, but can't come up with.

jollyreaper said...

"There will be Helium"

Now I feel like an idiot, because this is probably a riff on a line I should recognize, but can't come up with.


Probably not the best riff on it. Should be something more like "I will atmospheric scoop your milkshake."

jollyreaper said...


Stevo Darkly said:"I have altered the deal. Pray I don't alter it further."

I must be really tired, because this exchange brought to mind that scene being played by Yosemite Sam and Marvin Martian...


It would actually be a pretty fun setting for a comedic scifi story, tropes played for laughs rather than serious. Gas miners floating in the atmosphere of some improbable Bespin planet.

You'd need to have your rival factions with their giant cloud cities, improbable floating islands of rock and gas with weird flora and fauna, humans who have gone native... You'll have to have the son of a noble family exiled out here because it's considered to be the best place in the family business for him to cause the least amount of damage. He's under the impression that he who controls the hydrogen controls the universe. His advisors try in vain to explain how this is manifestly not the case. He's convinced he should become a leader of the aboriginals. The aboriginals think it's an incredible laugh and so play along with him, giving him a name in their own tongue that he believes means "great leader" but actually translates to "cosmic jackass."

A constant threat will be the adoption of robot labor which never works quite right because the owners insist on using anthropomorphic robots to reuse the existing equipment which doesn't make any sense. And these robots would play up all the silliest tropes in bad robot design and so completely and utterly fail at everything.

Something that's been hinted at in some scifi comedy is the cruelty of giving high levels of artificial intelligence to low-level tools. The first place most of us ever saw it was the animal-included appliances in the Flinstones. "SQUAWK! It's a living." Red Dwarf had the hyper-intelligent toaster. Nobody can forget Marvin from HHGTTG. Just imagine this case continuing. Throwing out obsolete electronics would be tantamount to murder.

Something else that would be amusing, the gas miner parachute. When I was a kid I'd had an idea that if pilots in planes carried parachutes, sailors in submarines should carry inflatable balloons in harnesses. When the sub has trouble, they jump out the door and pull the ripcord. The balloon would inflate like a reverse parachute and haul them to the surface. There could be similar fun with ridiculous technology like this in that kind of setting.

Anonymous said...

jollyreaper:" It would actually be a pretty fun setting for a comedic scifi story, tropes played for laughs rather than serious. Gas miners floating in the atmosphere of some improbable Bespin planet."
HAhahaha! :>
There is just too few good funny SF stories out there.

Ferrell

Milo said...

Jollyreaper:

"And these robots would play up all the silliest tropes in bad robot design and so completely and utterly fail at everything."

Don't forget the part where they try to kill all humans.

CRUSH! KILL! DESTROY!


"When I was a kid I'd had an idea that if pilots in planes carried parachutes, sailors in submarines should carry inflatable balloons in harnesses."

Hmm. You'd need to hold your breath until you reach the surface.

And I think ascending that rapidly causes decompression sickness (although does that still happen if you were in a properly pressurized atmosphere until a few seconds ago when the hull breached?). If you were close enough to the surface that pressure isn't an issue, then you can just swim to the top and don't need any fancy gadgets (unless, of course, you can't swim).

Thucydides said...

There will be Helium=There will be Blood

jollyreaper said...


HAhahaha! :>
There is just too few good funny SF stories out there.


Scifi is about exploring ideas and humor can often be about skewering the sacred. Taken together, it can be golden.

With the robots, it would be completely funny to have them make all these design compromises that ultimately end up with the robots being no more efficient than the humans they're trying to replace. They have to be humanoid to use the existing equipment, break down all the time so while they don't technically sleep, all the maintenance and parts swapping only leaves them good for about 8.1 hours of productive work in a day.

jollyreaper said...

And the company president gets a kickback on the fuel supply so while they could be running off of wall power, they instead have internal fuel cells that run off of a proprietary fuel source that has to be shipped in at great expense. And because of a screwup with requisitions, they're far too intelligent for the work they're being given which leads to poor morale and discipline problems. You can just imagine the sheriff shaking his head when he's having to haul a robot off to jail.

Hell, we can have a lot of fun with the idea of humans being stuck doing jobs that AI's refuse to do. "You have to make the machine smart enough to do the job but not smart enough to realize that he'd rather do something else with his runtime. There really are some things humans are better at than machines."

jollyreaper said...

You know, there's another cliche that's irksome. Whenever you have genetic engineering creating a brand new sentient lifeform, it's either going to devolve into the critter being pure evil (Species, Splice, etc), misunderstood and forced to evil (original Frankenstein's monster, Island of Doctor Moreau) or an on-the-run thriller (there was a recent book about cloning an extinct hominid, several others have done that.)

Why not throw it for a loop and make it a sitcom? Start with the Young Frankenstein premise that the crazy relative known for experiments has put the young relative in the will and left him the lab. When he gets there he finds out that he's not taking over the relative's experiments -- they've been complete successes. You've got several examples of uplifted and provolved critters in the lab and they're living just fine. All supplies are delivered by post, licensing fees for scientific patents pay for everything. All they need is a human to handle the personal interactions they themselves can't. The younger relative may be a scientist in his own right but is relegated to Renfield/Igor status. Amusing.

jollyreaper said...


There will be Helium=There will be Blood


Texas oil tycoon tries diversifying into helium mining, doesn't understand that you don't drill for helium, keeps dropping rigs into the heart of the gas giant.

Another crank character has the idea of getting access to the diamond heart of the gas giant and making squintillions but Fails at Science for the following reasons:

1. There's no currently feasible way of bringing the diamond up from the core.
2. There's already an affordable mass production method for creating perfect diamonds for industry and jewelry.
3. Even if artificial diamonds were no good, the expense of harvesting gas giant diamonds would likely make it cost more per ounce than antimatter.
4. If the kook did realize his goal of harvesting the whole rock, he would ruin the diamond market across all of known space.

You know what could also be fun as another Fail at Science, someone tries faking evidence to frame someone in a way consistent with the forensic TV shows but inconsistent with reality. I'm thinking the "zoom and enhance" trope. There's an excellent parody that shows the team looking at grainy surveillance video, zooming in on a car in the corner, zooming in on the license plate, zooming in on the screw holding the plate on, catching a reflection in the screw and enhancing to get a perfectly clear view of the killer. Epic fail.

Byron said...

You forgot the most important part: cloud pirates. I'd imagine that a blimp or dirigible is easier to maintain then a spaceship.
One other thing is that everyone's stuck here. Launch costs are going to be very high, making it really hard to get off.

Anonymous said...

Byron said:"You forgot the most important part: cloud pirates. I'd imagine that a blimp or dirigible is easier to maintain then a spaceship.
One other thing is that everyone's stuck here. Launch costs are going to be very high, making it really hard to get off."

You mean something like "Gloria Stuka vs. the Blimp Pirates of Venus"?

Ferrell

Milo said...

Jollyreaper:

"Texas oil tycoon tries diversifying into helium mining, doesn't understand that you don't drill for helium, keeps dropping rigs into the heart of the gas giant."

Guess they missed the memo about gas giants being made of gas.

Though if your science is sufficiently soft, this could actually work!


"If the kook did realize his goal of harvesting the whole rock, he would ruin the diamond market across all of known space."

Yes, but he would still get rich doing it. It's all the other diamond traders that lose out.



Byron:

"I'd imagine that a blimp or dirigible is easier to maintain then a spaceship."

Despite the cliche, blimps are going to be hard to use in gas giants. You need a lifting gas which is lighter than what the atmosphere is made of, and since the atmosphere is made of mostly hydrogen, basically the only thing hotter than that is superheated hydrogen. Yeah, that's a great idea.

You'd have far better luck with aerodynamic lift, in my opinion. Or hybrid designs that use hydrogen cells to reduce their density, but not actually to lighter-than-air levels.

jollyreaper said...


You forgot the most important part: cloud pirates. I'd imagine that a blimp or dirigible is easier to maintain then a spaceship.
One other thing is that everyone's stuck here. Launch costs are going to be very high, making it really hard to get off.


Oh, I'd imagine it would get even more interesting than that. There's the old seafarer's tale of the island that wasn't there the day before and you end up finding out it's really trees and sand on the back of an enormous sea beastie. So the natives would make use of critters that operate the same way. Here's the sky jelly, a big mass of floating gas and membrane that lives on photosynthesis and filter-feeds on cloud plankton. Mount some lightweight gondolas and you have a moving cloudbase. Your riding bats which are called bats because they're they don't resemble bats less than they don't resemble anything else, they can find perches on the bottom, hanging inverted to sleep.

Seeing as this is a semi-silly setting, maybe there's not any need to launch from the gas giant's surface but a partial beanstalk is used instead, one terminal station in space, the other down in the habitable zone of the atmosphere.

And seeing as there's a partial Dune parody in here, what should it be called? There's Dune itself, I believe a water world in the same universe was called Wave. What would you call this one, Wind? Cloud? Air? Nothingland? Planet Gas?

Byron said...

Milo:
Part of the scenario is a breathable atmosphere. That implies it isn't made of hydrogen. I understand your point, but how does everything stay up? Magic I mean antigravity? Use that instead, then.

Ferrell:
I guess so.

Thucydides said...

If Zeppelin pilots were having a difficult time dealing with Sopwith Scout biplanes in 1917, I doubt a 22nd century cloud pirate would have much more luck with the ramscoops dropping in from low orbit at Mach 25...

If a cloud pirate manages to escape being destroyed by a collision, exhaust plue or the shockwave of the ramscoop screaming through the atmosphere, he still might be caught unaware by the Moravec Tether plunging the catch bucket into the atmosphere.

These guys will be in the same position of fish caught inside an aquarium, with random "stuff" reaching down to do "things" to the tank.

Byron said...

Ramscoops as weapons? What? That seems like an expensive way to abuse hardware. That's what missiles are for.
It was an idea. Maybe they just use the blimp as base. Maybe they do something else.

jollyreaper said...

You mean something like "Gloria Stuka vs. the Blimp Pirates of Venus"?

Ferrell


Or maybe just "Blimpin' Ain't Easy."

If you're working with a limited economy, solid matter period would be the rarest thing in the atmosphere of the gas giant. We'd need to have some floating mountains just because hell, this is scifi and a gas giant without floating mountains in the atmosphere is BORING. But they'd probably end up being more like sky coral, lots of little lighter-than-air critters clumping together and creating islands of living material. If we assume there's some kind of pseudo-volcanism from deep within the core, dense material could be fired up into the atmosphere as particulates that would then mostly fall back down to the interior but would be available for filter-feeders. Heavier-than-air fliers could then eat the filter-feeders and their droppings at the floating cloud islands would provide additional nutrients.

So the only big question would be what would require mining operations to be handled in the habitable belt, something that couldn't be better done from atmospheric scoops coming into low orbit? Maybe when all is said and done it's slightly cheaper for them to siphon metallic hydrogen from the deep atmosphere than to compress it in orbit? To keep the comedic aspect there should be some element of ridiculous cost-cutting to rationalize everything.

jollyreaper said...


Despite the cliche, blimps are going to be hard to use in gas giants. You need a lifting gas which is lighter than what the atmosphere is made of, and since the atmosphere is made of mostly hydrogen, basically the only thing hotter than that is superheated hydrogen. Yeah, that's a great idea.


You're forgetting that this is a "ridiculous premise" gas giant like Bespin, a layer of breathable air at comfy temperatures in the mid-atmosphere. Played for laughs so characters would lampshade how impossible such a thing is. I'd be curious as to the kind of abuse you'd have to do to physics to put something like that together. I'm guessing that you'd need layers of heavier, non-breathable gas beneath the oxy-nitro or maybe some ridiculous heating device in the center of the planet to keep things moving?

I know the current theory is that the gas giants are not gas all the way through but should have a solid core, the assumption is that it would be diamond surrounded by a layer of metallic hydrogen.

jollyreaper said...

Milo:
Part of the scenario is a breathable atmosphere. That implies it isn't made of hydrogen. I understand your point, but how does everything stay up? Magic I mean antigravity? Use that instead, then.

Ferrell:
I guess so.


I'd run with anything lighter than air is cracking its own hydrogen out of atmospheric water or harvesting hydrogen from other creatures doing the cracking and the solid "islands" are mostly hollow and filled with hydrogen, the artifacts of living organisms, sky corals. Maybe let the humans have some manner of antigrav for some of the cloud cities because, let's face it, floating cities are one of the definitions of "rule of cool." And remember the whole setting is silly anyway so anything ridiculous about the premise is intentionally so. :)

Byron said...

We could go the Avatar route and use superconductor levitation.

Byron said...

That also provides a good reason to be there in the first place, now that I think about it.

jollyreaper said...

We could go the Avatar route and use superconductor levitation.

I'd thought about that but wasn't sure if it would be funnier to parody that or something else. Certainly you have strong magnetic fields around a gas giant but I don't know if it's enough to justify a floating mountain. I like to keep the physics bordering the absurd, not completely impossible. The impossible and incomprehensible should be kept to the human bureaucracies running the mines. :)

Milo said...

If you must have a cloudtop ecology, a Venus-like planet would be a much better place to set it than a gas giant. Venus blimps are actually even easier to use than Earth blimps, and so far more plausible to have evolved naturally by life forms that aren't just barely scraping by. There's still the question of why you would care to go there at all, and how you're getting your solid materials, but that can be handwaved given the deliberately silly setting.

Besides, Venus has rains of boiling acid. You can't tell me you weren't looking for excuses to include something like that!

Also, while we're on the subject of blimps, there's something I've always wondered: since they rise by being less dense than the surroundings, wouldn't the best lift be provided by pumping pure vacuum into cells rigid enough to stand up to the inwards pressure? That way you wouldn't need to worry about where to find lifting gas, although making vacuum might not be easy...

Byron said...

Milo:
Theoretically, yes, but the problem is that vaccum cells have to stand up under external pressure. If you pressurize with a gas, you just need a bag. The weight penalty is far too big.

jollyreaper said...

Also, while we're on the subject of blimps, there's something I've always wondered: since they rise by being less dense than the surroundings, wouldn't the best lift be provided by pumping pure vacuum into cells rigid enough to stand up to the inwards pressure? That way you wouldn't need to worry about where to find lifting gas, although making vacuum might not be easy...

My understanding was the extra buoyancy provided by pure vacuum is not that much better than hydrogen and is more than likely going to be offset by the unobtanium used to create the cells.

«Oldest ‹Older   201 – 400 of 418   Newer› Newest»