Saturday, July 4, 2015

The Space Authority and the Orbital Patrol

Triborough (Robert F Kennedy) Bridge, Port Authority of NY & NJ
Longtime commenter Ferrell made an observation about growing space traffic in the discussion on Adventures in Orbital Space that fits neatly into the setting portrayed in The Weekly Moonship:

At some point, traffic control and enforcement would be needed to keep ... impending chaos under control. As more people start working in orbit, the more positive control will be needed, traffic growing exponentially.

In a word, yes. A rudimentary framework for space traffic control already exists; I believe that orbital slots, at least in geosynch, are assigned by the International Telecommunications Union. But as space traffic grows, so will the need for traffic management and enforcement, as well as emergency response services. On land these tasks are commonly divided between police and fire agencies; at sea they are combined in the Coast Guard (at least in US practice).

The mission will eventually call for suitably configured and equipped spacecraft. And like the Coast Guard and its cutters, the agency and ships will in some broad sense be quasi-military in character.

Okay, let's be honest. This blog does not encourage war in space (or anywhere else), but that certainly hasn't kept me from writing about space warfare, or kept you from reading about it. But here I specifically want to look at what may be called 'organic' military or at least quasi-military activity in space - missions that relate to other human space activity, not just earthly power politics.

The distinction is important in more than one way. Navies have historically been 'organic' to sea trade (even if the first mission of the Royal Navy was and is to prevent another 1066). For that matter, armies have generally been 'organic' to the lands they defended, oppressed, or both.

Even more to the point, several great powers already have large military space armadas, and have for half a century. We call them ICBM forces, and neither as spacecraft nor as weapons are they really all that interesting. This isn't just Armageddon aversion - their 1950s predecessors, the B-52 and TU-95 Bear intercontinental nuclear bombers (both still in front line service, though mainly in other roles) had just as horrific a mission. But they were and are seriously cool airplanes, indeed acknowledged classics. You can enjoy and agree with the message of another Kubrick movie of the 1960s; those B-52 sequences still totally rock. Yee-haaaa! Yee-haaaa! Yeee-haaaaaaa .....

I think we can draw a broader message from this. The spacegoing equivalent of a coast guard cutter may not match the Romance quotient of a 44-gun frigate close-reaching to windward, a bone in her teeth and her guns run out. But it is probably more interesting technologically and operationally than a robotic battle station designed to vaporize other robotic battle stations or the occasional city.

And, most of all to the point, the coast guard cutter is in almost every case a far better delivery vehicle for a payload of adventure.

So how does it emerge? I will start with the agency that deploys it, the Space Authority. This rather bland name is inspired by the Port Authority of New York and New Jersey, an agency that in its mid-20th century heyday, under Robert Moses, was notoriously powerful and independent, and reshaped New York City (albeit in ways that are now widely deplored).

The Space Authority was founded in 2022 - or it might have been 2012; I haven't double-checked, and in its early decades the Authority was all but invisible. Its overall mission was and is to co-ordinate space activity, assigning orbital slots, enforcing safety regulations, and such. The Authority was set up by the major space launch players, but its guiding force was - and this is not a contradiction in terms - a shrewd, tough, and above all visionary bureaucrat.

To avoid endless wrangling over a tiny budget, this individual proposed a dedicated funding stream, a $10,000 fee for every ton placed on orbit. To the power players this was convenient and cheap, the fee coming to about 0.1 percent of contemporary launch cost. Even to penny-conscious Elon Musk it was chump change (and Musk might well have seen through the game and still figured it was worth playing, and paying).

And since space traffic had been fairly steady for decades, a few hundred tons annually, hardly anyone expected conditions to change. The Space Authority had just enough money, a few million per year, to rent some office space in Geneva or wherever, and hire a couple of sharp young attorneys as staff. Space law enforcement, in this early era, did not mean spacecraft with flashing red lights. It meant a letter, hand delivered on real paper (lawyers likes that stuff), directing attention to Section 28, Subparagraph h(3), 'Penalty for Noncompliance'.

Time marched on, and space traffic volume grew. By the time the moonship Henry Mancini is docked to Airlock 10-A, 100,000 passengers and 70,000 plus tons of cargo payloads are going into space every year, plus the upper stages of the shuttles that put them there. The Space Authority budget is now on order of a billion dollars a year, current value. Still chump change by Pentagon standards, but this is a real budget, enough to charter or buy and equip a couple of ships for special missions - and develop a more capable, purpose-built model. The need may not yet have fully arisen at the level I described, with its 6-8 passenger ships operating beyond low Earth orbit. But it is clearly on the horizon.

The primary mission of these first Patrol ships will likely be the noblest: space rescue. Rescue in deep space is problematic at best; the distances are simply too vast. By the time you reach a stricken ship or outpost it probably won't have any survivors left to rescue. But rescue in orbital and local space is a different matter.

We have already had a case where space rescue could have made all the difference. Had the extent of damage to Columbia's heat shield been recognized, a rescue mission would have been feasible in principle. I sadly suspect that NASA closed its eyes and grit its teeth because no rescue was possible in practice. Even the Russians, with their simpler, robust architecture, could not have cued up a double Soyuz mission in time, and Columbia was on an orbit that Soyuz, from its high-latitude launch site, probably could not reach.

But once space rescue is practical it is necessary, and the Authority needs a ship or two that is up to the job. This means sacrificing operating economy in favor of flexibility and performance, specifically the ability to deploy on short notice and reach as many orbits as possible, meaning plenty of maneuver capability, AKA delta v. Onboard equipment and facilities, in addition to sick bay, likely include storage and support for taxi craft and robo pods used to work around crippled, possibly tumbling spacecraft, plus a miniature onboard Mission Control for directing operations.

The first such ships will be handbuilt prototypes, thus costly; the Authority might need to issue revenue bonds to fund the development program. Follow-ons will be less expensive, though still more than commercial models since the mission is more demanding. Say $200 million per ship for a 100-ton ship (unfueled), and $60 million per year to keep each in service, plus propellant for training missions. Perhaps $150 million annually per ship, all up, so the Authority can keep three or four in service.

And it possibly has not escaped your attention that the major characteristics of these ships - their flexibility and performance - are very much what you would expect of warcraft. (May the Episcopalian God of my childhood forgive me, agnostic that I am, for perverting angels of mercy into angels of wrath.) Throw in fittings like those (potential) weapon bays and CIC or tactical control center and you have the raw material of a handy basic space warship.

Even militarized, these Patrol ships would be no match in sheer firepower for the sorts of weapon platforms the great powers might deploy. But they are far better suited to exerting a presence in orbital space. Über battle stations leave policymakers with a pretty stark options menu - nothing between issuing a sternly worded letter of protest or blowing someone up. A Patrol ship can switch out the medics for a SWAT team, go out to any orbit, arrest someone, and haul them in to face charges.

And that is how you effectively and flexibly exercise power, or dare I say Authority, across local space.

What are the chances of some such agency and some such ships emerging? Given the scale of space activity I have portrayed - hardly a given - I'd actually rate the chances moderately high, say five percent to 20 percent. Someone will need to do it. The great powers won't trust each other, and won't want to spend their own money on forces suited to keeping order in orbit rather than overawing their terrestrial rivals. Business interests will want some law and order up there without getting too entangled in international power politics. Yet the outcome suggested also would mark, quietly, a beginning for space-centric political structures.

On Independent Orbit?

Potentially, at least for purposes of opera, it might be a good deal more than that. As noted here before on this historically significant anniversary, the Revolt of the Colonies has been a long-standing theme in space-oriented SF; particularly, for obvious reasons, 'Murrican space SF.

In the rocketpunk era the Space Patrol was commonly understood to be an arm of the American Empire Terran Federation. As such it would be cast in the role of the Redcoats in any Independence Day scenario. (Though, notably, Heinlein in Between Planets did not call the Federation forces, or any component of them, the Patrol; that name was reserved for stories where the Patrol and the Federation itself were good guys.)

But the Patrol as outlined above arises in different circumstances, where there is no Federation, certainly nothing like a world state, only the great-power muddle we have known since 1648 - or perhaps even a more thorough muddle, known to students of international affairs by the wonderfully Game of Thrones-esque name of neomedievalism.

In such circumstances, as suggested above, the Patrol is not an instrument of any terrestrial power, but one that arises from the circumstances of space itself, politically embodied in this account by the Space Authority. No one on Earth quite owns it, or can even agree on who should own it.

There would likely be no Declaration of Independence, no need for a gifted rhetorician to remake poor old George III into Caligula. Possibly the last thing the Authority wants is to call that kind of attention to itself and its expanding role, and gaining a seat in the UN General Assembly, or successor body, is the least of its priorities.

Unless, of course, the overriding demands of story call for a Concord, a Saratoga, a Yorktown. In that case, have at it.

Port Authority Police Patch


The image of the Robert F Kennedy or Triborough Bridge, built by the Port Authority in the Robert Moses era, comes from a blog about NYC area highways. Apart from my institutional reference, what does it have to do with space? Who cares? Bridges are always cool.

The image of a Port Authority police patch comes from a police officers' organization website,

Friday, June 26, 2015

The Weekly Moonship

Von Braun Moonship

The phrase sticks in my mind. I surely read it in an SF novel, or more than one, and perhaps in a variation like daily moonship. Since it is an evocative phrase, at any rate to me, let us evoke something from it.

The weekly moonship. Just the name tells us a good deal about Luna's place in human affairs: we go there every week, at least most weeks. It might be more; perhaps connecting flights depart from Cape Canaveral on Mondays, Baikonur on Tuesdays, and so on. But let us modestly stick to a single weekly moonship.

Not only do we know that we go to the Moon weekly, we can venture a broad guess as to how many people make the trip. Our moonship surely carries more than a couple of passengers, fewer than a thousand; a broad range might be 10-200. We will say fifty: our moonship has the seating of a 1950s airliner or transcontinental train coach.

Since the Luna round trip takes a week, weekly service probably means two passenger ships taking turns, with a third - perhaps an older model, less economical to fly - in reserve. For landing on the lunar surface, a shorter mission, one lander will do, with one in reserve. One or two ships suffice for other distant orbits, so altogether we have a generous half dozen passenger ships working the Moon and other locales in the outer reaches of Earth's orbital space.

And we will suppose that these ships mostly fill their seats, unlike the rather similar spaceliner in 2001 that carried Heywood Floyd to the Moon in solitary VIP splendor. So about 2500 passengers travel to Luna each year, at least to lunar orbit; most continue on down to the surface. At this stage nearly all are making the round trip; if most are serving six-month rotations we have about a thousand regular residents of Luna Base and its outliers.

Passengers making shorter stays nudge up the lunar population - as does anyone staying on past six months. Add a few hundred people in lunar orbit, or other distant orbits, for a total of roughly 2000 people in the outer orbital zone.

Beyond that zone we might suppose that about fifty people are on or orbiting Mars, with a similar number aboard exploratory missions elsewhere - perhaps a half dozen active deep space ships that carry human crews, plus some robotic freighters that can take slower orbits.

If the deep space missions use electric propulsion they depart from high orbits or at least refuel and take crew aboard there; if they use chemfuel or (properly shielded!) atomic rockets they blast straight out of low orbit for maximum Oberth effect. In that case the human presence in outer orbital space may still be confined largely to the Moon itself, and lunar orbit.

But we are not mainly concerned here with deep space. Anyway,  you cannot yet buy a ticket aboard the biennial Mars ship the way you can with the weekly moonship.

Looking inward, towards Earth, we can expect to find more people.

Geosynch is economically important but surprisingly difficult to reach - nearly twice as hard as jumping over the Moon, as Apollo 8 did. Geosynchronous orbits are awkwardly placed: High enough that it takes a big burn to get there, close enough, thus with high orbital speed, that it takes sizable burns to match orbit, then head back down. So geosynch traffic is purely utilitarian, and the human presence perhaps less than in lunar orbit. A single passenger ship can serve this route, with one in reserve.

Low Earth orbit is a different matter. It is the closest place in space, the easiest and cheapest to reach, and for many purposes and most passengers that is enough. Tourists can float and gawk as well here as anywhere. Virtual tourism is also served; Xollywood can and will use low Earth orbit as stand-in for the universe.

So ... taking a not too deep breath, let us say that there are 10,000 people in low Earth orbit at a given time, ten times the lunar population. For those who are staying weeks or months in space, this corresponds to a tenfold increase in traffic volume, about 25,000 people going up every year for fairly long stays.

But low Earth orbit allows quicker trips than the week-long journey to the Moon. So let us say that about ten percent of the people in low orbit are visiting for short stays of less than a week, adding about 50,000 annual trips, for a total of 75,000.

And let us round things out by adding 25,000 tourists who simply go up and down, never exiting the shuttle, but going back with memories.

Thus, 100,000 (!) passengers to space every year, a few hundred daily. If our passenger shuttles also carry fifty people, there are five or six daily flights to orbit worldwide. Allow, 'conservatively,' a one week turnaround, and there are about forty shuttles in the service rotation. Perhaps fifty in the active fleet, allowing for maintenance cycles, some in reserve, and so on.

In human terms this is some serious traveling. We can suppose that the baseline human lift cost to low orbit is perhaps $50,000 (in present day USD), but that is an average. Business travelers will pay another $20K for a reserved ticket and 'complementary' cocktail; most pay cheerfully because they aren't paying; their company picks up the tab.

Tourists fly standby and bring their own libations. They also benefit from the economics of unsold seats on the bus. The seats go into orbit whether or not any passengers are floating above them. The direct cost of lifting each passenger is really only a ton or two of propellant, at Earth industrial price, plus an airline meal.

Which means that some seats will be sold pretty cheap, and even us peasants can pass on that new car, and instead spend a day looking the universe in the eye.

The payload we care most about is us, but we must say a little about cargo traffic as well, especially since much of it also involves us intimately: food and shelter.

At this level of development, growing food in space is still in trial stage; daily sustenance comes up from Earth. My baseline 'cheap' orbit lift cost is $100,000/ton, $45 per old fashioned pound. That is roughly ten times the grocery store price of everyday goods, but not much more than the price of luxury items.

People in space will eat well, because the lobster doesn't cost much more than the rice you serve it with. In general, everyday economics has the boom-town combination of sky high all-around prices with peculiar twists.

You also need a place to stay. The most massive and crucial structural works in space are not ships but dormitory habitat modules: where you live, if you are living in space or on the Moon.

My baseline guesstimate for these is about 20 cubic meters and 10 tons per person. If you stripped all the laboratory equipment and such out of the International Space Station, beefed up life support, and fitted its pressure modules out like a Pullman train, it would have roomettes for some 45 people, which sounds about right.

(For really long term occupancy, including children and pregnant women, you need another 5-10 tons of radiation shielding. On the Moon you can just pile up regolith, AKA lunar dirt, over the hab structures. But at this stage we only need a few fully shielded habs.)

Booking a hab roomette as a hotel room might come to about $10,000 per night minimum - more inflated than the price of food, because the thing is so heavy. There may be bad hotels in space, but at this level of development there are not yet any cheap ones.

For 10,000 people in low orbit, thus about 100,000 tons of habitat, plus we might suppose another 100,000 tons of other facilities such as those Xollywood sound(less) stages. Annual orbit lift needed to support, maintain, upgrade, and expand it all might come to 30 percent of the total, 60,000 tons.

Suppose we have two main classes of cargo lifters. Most carry up about 25 tons, and are cargo counterparts of the passenger shuttles. About a fifth are heavy lifters, 100 tons to orbit, carrying about half the total load. Average payload is 40 tons, so 1500 flights per year, about five daily including one heavy lifter.

The fleet of cargo shuttles comes to about forty vehicles, so altogether our orbital shuttle fleet approaches a hundred (two-stage) vehicles.

The thousand people on the Moon, and the other thousand or so elsewhere in orbital space, also need room and board - coming to some 40,000 tons of imported structures, and about 12,000 tons per year in up-bound cargo traffic from Earth, half of it going to the Moon.

To carry this cargo up we will need a few more shuttles, and to take it on outward we need a small fleet of cargo ships. Let each carry 60 tons of cargo - comparable, for these longer trips, to the 50 seats aboard the passenger ships - and we have a couple of cargo moonships per week as well as the passenger ship. Altogether the cargo fleet working beyond low Earth orbit will number about a dozen ships - add the passenger fleet for a total of around 20.

So we come full circle to the weekly (passenger) moonship. A ticket will not come cheap, because lunar propellant is probably not yet competitive for use on low Earth orbit.

Propellant sent up from Earth to an orbital depot is a relatively simple bulk payload suited to maximum streamlining of operations, and the price might get pushed down to $50,000 per ton. A ton of lunar propellant delivered to low Earth orbit needs at least another ton or so to get it there, even with solar electric kites for the second leg of the trip, so the price point to match for lunar production is around $25,000 per ton at the source.

Moreover, rocket propellant uses a larger proportion of hydrogen than ice contains, thus perhaps two tons of ice per ton of propellant extracted. Altogether, to make lunar propellant competitive in low Earth orbit you may need to bring production cost down to $250 per ton of lunar regolith that must be crunched to obtain the ice - a pretty demanding order for mining on the Moon.

Lunar propellant is much more competitive in lunar space, versus propellant lifted all that way from Earth, but low Earth orbit will favor Earth-sourced propellant for a long time, even permanently if launch costs come down enough.

Our weekly moonship needs about four tons of propellant per passenger, costing $200,000 on orbit (and not counting, for Earth passengers, their ticket to orbit). All in all, upwards of a quarter million on average to fly to the Moon. Robert Heinlein, writing in 1949, pegged the full Earth-to-Moon lift at $30 per pound - equivalent, at current prices, to $299.75 (almost exactly 10x inflation), or $660,649 per ton. So we are beating Heinlein's price hands down.

That said, even filling that last empty seat will set you back a minimum of $30,000 in propellant to lift you and your baggage. But hey, a best-case total of maybe $50K or so to fly to the Moon? Not shabby.

Stepping back, the vision I have sketched here looks very much on the same scale as what Kubrick and Clarke gave us in 2001: A Space Odyssey. One estimate for the mass of Space Station V in the film comes to 68,000 tons, about a third of my estimate for total low-orbit presence.

The operating technology I've presumed - chemfuel rockets for all routine operations - is speculation-free, aside from the bit of magitech faerie dust needed to make space operations routine. We probably could have done it by 2001, had space development continued at the white hot pace of 1968.

The whole shebang - shuttles, orbital stations and habs, moonships and Luna base, all of it - has a combined mass somewhat less than 300,000 tons. By my million-dollars-per-ton guesstimate, which applies to commercial airliners - and expendable rocket stages - today, it would cost us not quite a third of a trillion dollars to build it all, and $100 billion or so to operate it each year.

In an earlier development stage, when spacecraft are still largely handbuilt prototypes, the same money will only buy about a tenth as much - still a respectable start: a thousand people in space, a hundred on the Moon, the cost falling and development expanding as experience is gained and economies of scale kick in.

But enough of the big picture, except for the biggest picture of all, the one outside the viewport. Ladies and gentlemen, moonship Henry Mancini is now ready for boarding at Airlock Ten-Alpha. Please glance at the ticket scanner as you pass by, and have a wonderful trip! Damy i gospoda, kosmicheskiy korabl' na Lunu Genri Manchini gotov ...

Kubrick's Moonship


I had intended to write about Ships for the Orbital Patrol. But the whole subject of 'local' space keeps expanding, and what can I do but expand along with it?

The first image, from an online model store, is a 3D rendering of the Von Braun moonship proposal of the 1950s. It carried about fifty people, but obviously did not aerobrake on the return trip. The second image, from Space Collective, shows the lunar liner from 2001.

Monday, June 22, 2015

Adventures in Orbital Space

Apollo 8 above Luna

Space is vast. But most of it is empty, and we pass through only to get somewhere. The people who live and work in space will mainly do so somewhere, in some region of local space, most often a planet's orbital space, including the moon systems of giant planets. 

So to celebrate my return to regular blogging (touch wood!), some old fashioned goodness: ships and travel in orbital space, mainly Earth's: exactly what it says on the tin. 

But first of all I want to thank all of you who have visited Rocketpunk Manifesto during my prolonged absence. Especially I thank the commenters here for keeping the conversation going, and in exemplary fashion. You are why I am back here to talk more about space.

Orbital and local space get lip service, with most of our attention drawn to the grandeur of interplanetary or interstellar travel. But orbital space, and the ships that ply it, deserve more attention.

Every journey from world to world passes through orbital space; indeed begins and ends there, unless your starships land directly on planets. A routinely spacefaring future will surely have many stations and other habitats in orbital space, or on the Moon or a counterpart. And every world's orbital space is unique, shaped by its particular circumstances. Mars has two tiny moons, close in; Earth has a single enormous one at the far fringes of its orbital space.

Local space may also emerge in regions far from any large body, perhaps because of interesting concentrations of small objects, e.g. asteroids, or simply because habitats have congregated there. Wherever people gather in space, with regular traffic among them, there is a region of local space.

This traffic has a tempo and flavor quite different from deep space travel. Travel times are short: four hours to geosynch, the popular geosynchronous 24-hour orbit; three or four days to the Moon.

Spacecraft in orbital service will range from moonships down to what I call taxis, minimal space capsules used to move between larger spacecraft that have made rendezvous but are not docked together. Most local craft will be fairly small, because they can be. Passengers can be accommodated coach fashion, in airline type seats (or just above them, loosely strapped in). Crews may have a little more room to float around, but probably do not live aboard their craft between missions.

Maximum design endurance is perhaps two weeks, the current standard. The distinction between ships and stations, which can be a bit blurred in deep space, is sharp in local space: stations and habs you live in versus craft you travel in.

Passenger ships surely have viewports, because the views are spectacular. Orbital space itself is vast, a thousand times a thousand miles across, but it does not quite share the chill loneliness of deep space, weeks and many millions of kilometers from anywhere. In all, there is something comfortably human about travel in local space, especially a world's orbital space.

And this travel will most likely be aboard plain old chemical-fuel rocket ships, surely into the midfuture, and even in what the commenter community here has dubbed the PFF, the plausible far future.

My text for this sermon is the set of delta v maps, especially the first of them, at the still ever-growing Atomic Rockets site. These maps show the combined speed changes, delta v in the biz, that you need to carry out common missions in Earth and Mars orbital space, such as going from low Earth orbit to lunar orbit and back.

Here is a table showing some of the missions from the delta v maps, plus a few others that I have guesstimated myself:
Low earth orbit (LEO) to geosynch and return 5.7 km/s powered
(plus 2.5 km/s aerobraking)
LEO to lunar surface (one way) 5.5 km/s
(all powered)
LEO to lunar L4/L5 and return* 4.8 km/s powered
(plus 3.2 km/s aerobraking)
LEO to low lunar orbit and return         4.6 km/s powered
(plus 3.2 km/s aerobraking)
Geosynch to low lunar orbit and return* 4.2 km/s
(all powered)
Lunar orbit to lunar surface and return 3.2 km/s
(all powered)
LEO inclination change by 40 deg* 5.4 km/s
(all powered)
LEO to circle the Moon and return retrograde* 3.2 km/s powered
(plus 3.2 km/s aerobraking)
Mars surface to Deimos (one way) 6.0 km/s
(all powered)
LEO to low Mars orbit (LMO) and return 6.1 km/s powered
(plus 5.5 km/s aerobraking)
* Not in source table; delta v estimates are mine.

Two things stand out in this list. One is how helpful aerobraking can be if you are inbound toward Earth, or any world with a substantial atmosphere. Many craft in orbital space will be true aerospace vehicles, built to burn off excess speed by streaking through the upper atmosphere at Mach 25 up to Mach 35.

But what really stands out is how easily within the reach of chemical fuels these missions are. Chemfuel has a poor reputation among space geeks because it barely manages the most important mission of all, from Earth to low orbit. Once in orbit, however, chemfuel has acceptable fuel economy for speeds of a few kilometers per second, and rocket engines put out enormous thrust for their weight.

In fact, transport class rocket ships working routes in orbital space can have mass proportions not far different from transport aircraft flying the longest nonstop global routes.

A jetliner taking off on a maximum-range flight may carry 40 percent of its total weight in fuel, with 45 percent for the plane itself and 15 percent in payload. A moonship, the one that gets you to lunar orbit, might be 60 percent propellant on departure from low Earth orbit, with 25 percent for the spacecraft and the same 15 percent payload. The lander that takes you to the lunar surface and back gets away with 55 percent propellant, 25 percent for the spacecraft, and 20 percent payload.

(These figures are for hydrogen and oxygen as propellants, currently somewhat out of favor because liquid hydrogen is bulky, hard to work with, and boils away so readily. But H2-O2 is the best performer, and may be available on the Moon if lunar ice appears in concentrations that can be shoveled into a hopper. Increase propellant load by about half for kerosene and oxygen, or 'storable' propellants.)

Propellant thirstiness does impose odd logistics and economics, because every ton of payload needs three or four tons of propellant to dispatch it on each leg of major trips. Inter-orbit tankers and other bulk cargo can ride slow solar-electric kites, taking a couple of weeks to spiral up and down to geosynch, a month or more to the Moon and back. But these are not for human travel; besides being slow, they spend days at a time in the Van Allen belts.

Nuclear thermal rockets, NTRs - the original atomic rockets - are one alternative, but a limited one. For local operations their engines must have all-around shielding, because an unshielded nuclear reactor poses a low-level but significant long term radiation hazard out to an amazing distance in space - about 100,000 km radius for a gigawatt reactor. This would not make for good neighbors in local space.

Heavy shielding limits nuclear propulsion to larger spacecraft, probably in the thousand-ton class, and with relatively sluggish performance: landing even on the Moon is problematic. Big ships do get the most saving from halved propellant consumption, but nuclear propulsion is not a panacea for travel in local space. Torch-level drives would be worse; torchships must normally stay out at the fringes of a world's orbital space, met by rockets to ferry passengers up and down.

Other possible options - laser propulsion or other beamed power, mass drivers, and so on - have their own constraints. And even outright magitech drives will be hard put to match the flexible power of rockets for people in a hurry. Not to mention that if you want opera, big rockets are positively Wagnerian.

This is (almost) the final thing to note about travel in orbital and local space: how operatic and rocketpunk it is. Rocket ships! A world swelling up in the viewport, becoming a landscape below you as your ship arcs down to a surface landing ...

Aboard a ship that might even be streamlined, with wings or fins, built for aerobraking as well as landing on airless worlds. Ordinary transport types would not combine these features, but emergency response craft, built for versatility rather than economy, might well do so. We will look more closely at such ships in our next exciting episode.

But the most astonishing thing about travel in local space is that it not only is operatic and rocketpunk, it is also real. Forty-six years ago next month we carried out the combined lunar orbit and lunar landing missions, returning safely to Earth. So the only real matter for speculation is not whether we can cross orbital space to the Moon, or even (details aside) how, but only when we will decide to go back again.


The image comes from a blog post reflecting on Apollo 8, which as the author says deserves to be more remembered. I remember looking up at the half moon at twilight on a clear Christmas Eve, in awe that there were people up there.

Sunday, October 26, 2014

Catherine of Lyonesse

Is that a gorgeous cover, or what?

Considering that the book has now been out, in the UK, for about ten weeks, it is high time and then some that I highlighted it here, (But possible good news on my sluggish posting - fingers crossed! - below.)

How it is selling, as yet I have no idea. On Amazon, not very much, but I am told that it is not a "major channel" in British trade publishing sales, and the fact is that a first novel depends heavily on old fashioned sales off the bookstore shelves.

A public acknowledgement and thanks is due - and overdue - to Tamora Pierce, official Friend of this Blog, and the faerie godmother of Catherine over many years. Also to blog reader and occasional commenter Anita, who originally worked out the genealogy at the front of the book. But I assert sole credit for mistakes.

I should also tip my hat to a reader, 'Gracie,' who posted a wonderful reader review at Amazon. Five stars are always wonderful, but her elegant and insightful comments even more so. Courage and panache, indeed!

And also a tip of hat to a couple hundred of Tammy's fans who responded to her wonderiffic Goodreads review by putting CoL on their to-be-read lists.

Finally, I should say that while the ebook version is not currently available in the US (pending a hoped-for US edition), the paperback version can be ordered from anywhere.  :-)

Biochemistry Note

As I've noted here previously, the life sciences tend to get relatively short shrift in space discussions. I rarely remember life support ecology getting anything like the detailed discussion given to shiny stuff like propulsion systems.

But these things matter, as I have been reminded by being diagnosed with diabetes (type 2 - the kind that doesn't require daily insulin), AKA the American disease, the result of a lifetime of bad dietary habits coming back to bite me. I seem to be responding well to treatment, but one effect of the disease, relevant to this blog, is fatigue.

So, as treatment progresses, I hope to overcome that and start posting here more frequently.

And a Return to Space

Those loyal readers who still drop by here from time to time will surely (?) be glad to hear that I have lately been reading and thinking more about space again. I hope to post some of the results here soon. Meanwhile, I encourage everyone to (re)visit the wonderful Atomic Rockets website, which has been greatly expanded over the past few years even as this blog went relatively quiescent. 

Talk to you again soon!

Wednesday, July 9, 2014

Worldbuilding and the Hazards of Canon Fire

The Moving Finger writes, and having writ,
Moves on: nor all thy Piety nor Wit
Shall lure it back to cancel half a Line,
Nor all thy Tears wash out a Word of it.

-- Omar Khayyam

The moving finger can even, as in this case, return after an indecently long interval to write more.

But most to the point, the moving finger, by hitting the publish button, establishes canon. What previously were tentative, fluid possibilities are transformed into either fixed facts or equally fixed nullities. Even the digital era has not, so far, changed this in essentials - ebook editions, at least from commercial publishers, are as fixed as their print counterparts.

Thus, in the course of the spring, Catherine of Lyonesse has taken on its final, official form, the text gradually setting like concrete. Events and details that previously were fluid, contingent, subject to revision, are now fixed in place beyond the reach of piety or wit. Now they are canonical, or will be come the official publication date - August 14 - and the release of the book.

This effect of canonicity does not depend on the technology of print: Omar Khayyam wrote long before the printing press. But print - generating numerous identical copies of a text - surely amplifies this effect. Getting the first couple of copies of C of L off the print run was a wondefully solid experience.

Even more wonderfully the copies smell like books.

And the canonical version is right there in cold print.

In Catherine of Lyonesse I did little worldbuilding of the classic SF/F sort. The world of the book is meant to be evocative of our own, similar enough that the mechanics did not need to be worked out and tested for fit. The population and technology of Renaissance France were sufficient to support the French royal court; given a comparable kingdom, the royal court of Aquitaine did not need to be explained, only invented.

As a result, I nearly got caught by a stray round of canon fire. At some point in writing the manuscript I needed to mention a former king of Lyonesse, one of Catherine's ancestors, and made him Edmund II. The name was intended simply to evoke the Edwards of Plantagenet England.

Much later in the process I drew up a family tree, and merely listing successive kings hinted at a background arc: a failed king; a son who conciliates his subjects; a grandson who takes advantage of the revitalized monarchy to beat up on the neighbors. And so it turned out that the Agincourt-esque battle mentioned in the book would fit better with Edmund III.

By then I'd long forgotten that the manuscript itself still said Edmund II. I didn't catch the mistake until the very end of the proofing process.

Did it even matter? Within the book itself, not at all. Nothing in the text would tell the reader that Edmund le Conquérant should refer to Edmund III, not his father, "Good King" Edmund II - who is not mentioned in the book at all, not even indirectly.

But if I had not caught the discrepancy, I would have been put in a slightly odd quandary going forward. If there is a sequel, it probably will mention Good King Edmund. But then, which Edmund would he be? Would I keep the history arc I inferred from the genealogy, and ignore the regnal number given in the first book? Or accept the printed text as canon, and mentally reconstruct the dynastic history to fit?

Since I did catch the discrepancy before the book went to cold hard print, I was spared that sort of reconning. At least in this case. No doubt further journeys in sequel-land will reveal things I'll wish I had done differently in the first book, but that is a different matter.

More elaborately constructed worlds give their authors a better chance to catch mistakes - but also expand the universe of possible mistakes, so the tradeoff is probably a wash. And canonicity itself is arguably a geek obsession. Major sloppiness in a setting can break the spell - the willing suspension of disbelief - especially if readers can't be sure what merely factual matters in the story they can rely on. But most concerns about canon are just pedantry fuel. Which won't keep me from fretting about them.


The image, via Wikipedia, shows modern reproductions of 16th century naval guns from the wreck of Henry VIII's Mary Rose.

Saturday, January 4, 2014

Wine-Dark Sea

Not to belabor the obvious, but I have taken a long and unplanned vacation from this blog. After more than six years it has become a challenge to come up with topics that have not already been beaten to death here.

So I will make absolutely no promises about frequency or consistency of posting, but here you go!

There is a curious enchantment to Dark Ages. They are dark mainly to us, with few if any written records, yet they loom large in our imaginative heritage.

The Dark Age of Greece - by convention it is in the singular, not 'Dark Ages' - might be dated with traditionalist pseudo-precision as running from 1174 BC to 776 BC. The end date is the first Olympiad, the earliest recorded date of 'historical' Greece. The start date is ten years after the fall of Troy, when Odysseus finally gets back to Ithaca, last of all the surviving Achaean heroes to make his way home.

The traditional dates for the Trojan War itself, 1194-1184 BC, were an estimate by Eratosthenes, better known in geekdom for his impressively accurate computation of the size of the Earth. But the first curious thing about the Dark Age of Greece is that his date for the fall of Troy is also impressively accurate, even though it was based on premises that were shaky, obscure, or both.
The current archeological dating for the destruction of Troy VIIa - a destruction apparently due to war - is given as 1230-1190/1180 BCE, a range that just neatly overlaps the traditional date.

True that Eratosthenes' dating was only one of several classical estimates for the fall of Troy, and if you include enough of the others you can make a plausible case that Eratosthenes merely got lucky. If you scatter a dozen estimates over a 200 or 300 year period, one of them is likely to fall within a couple of decades of any given date.

But 1184 became the standard traditional date for the fall of Troy. Score one for Eratosthenes, not to mention Homer.

To us the oddest episodes in the Odyssey may be when Odysseus' son Telemachus visits Sparta and finds Menelaus and Helen living in comfortable domesticity, as though all that awkward business about Paris of Troy had never happened. Other homecomings, the Nostoi in Greek tradition, were more turbulent.

Odysseus, not home yet, would have his own troubles, though they seem to end well for everyone except those annoying suitors (and the servingmaids who had been overly friendly with them). Most notorious of the homecomings was that of Agamemnon, King of Men, finished off in his bath by wife Clytemnestra. (She arguably had good reason.)

To judge by the archeological record, however, practically all of the homecomings must have gone badly. Every Mycenaean palace was destroyed, with the sole exception of the (rather minor) palace at Athens. As a further complication the wave of destruction - one scholar has dubbed it simply the Catastrophe - peaked right around 1200 BCE, slightly before the putative date of the Trojan War.

What sticks most in my mind is sandy Pylos, the city of wise old Nestor. Telemachus also visited Pylos in his journey, where he found Nestor leading his people in sacrificing bulls (or was it oxen?) to Poseidon. All seems to be going well for the Pylians - if Homer had wanted Foreshadowings of Doom in his narrative, he could have provided them, and he doesn't.

In fact, however, sandy Pylos went down in flames circa 1200 BCE. And unlike Mycenae, which struggled on through a couple of archeological destruction layers before final abandonment, Pylos went down for the count.

Left in the smouldering ruins were clay tablets, fortuitously baked in the conflagration, on which scribes had carefully recorded all the unromantic details of Bronze Age palace management.They also provide the Foreshadowings of Doom that immortal Homer does not: Watchers have been dispatched to guard the coast, some 600 rowers are being mustered, and there are hints of an emergency human sacrifice.

The fashion in the fairly recent past was to downplay any real connection between Bronze Age events and the Homeric tradition. The magisterial Moses I Finley dismissed any Bronze Age element in the epics as a mere few Mycenaean 'things.' Lately the scholarly fashion cycle seems to be going the other way, helped along by other fire-preserved clay tablets, from Hittite archives, that mention a place called Taruisa or Wilusa, and troublesome people called Ahhiyawa - evoking Troy, its alternate name Ilios, and the Achaeans, sackers of cities.

For historical, or para-historical fiction, this would be more than enough. A lot of plausible reconstruction of events can be slipped through the error bars in archeological dating. If Troy fell in 1230 BCE, then whatever happened to Pylos happened a generation after Telemachus' visit, give or take, and had no reason to be hinted at in the Odyssey. Perhaps it belonged to a different story line.

But that is the mystery and enchantment of the Greek Dark Age. Moses I Finley may have been wrong to dismiss 'Mycenaean things,' but he is right in saying not to judge a culture only by its material poverty.
An oral tradition persisted and developed through its obscure generations.

The tradition did not preserve everything. If there was ever an epic sung of the fiery end of Pylos, it vanished nearly without trace. (A sketchy account held that Nestor's descendents were exiled from Pylos, turned up in Athens, and eventually founded Ionia.) But the tradition did preserve some things, however much refracted by oral transmission.

It is unlikely that we will ever find a source document that directly records the specific people and events that have come down to us as the wrath of Achilles and the wanderings of Odysseus. We glimpse them - vividly so - across a wine-dark sea of time.


Obligatory space reference: When your subject is Odysseus, the Major Tom of Bronze Age heroes,  you don't really need an obligatory space reference. But I provided one anyway.

The image of an archaic era Greek galley comes from a Project Gutenberg ebook.

Monday, September 23, 2013

Vandenberg Spaceport

I'm baaaaack!

Yes, the hiatus has been far too long - I kept thinking 'just another day or two,' after a move, working on Catherine of Lyonesse, an annoying and voltage-draining sinus infection, and, well, work.

The move means a regretful farewell to the F line streetcars, 100,000-ton containerships, and more places to eat than we could ever possibly try. On the other hand, the Central Coast does have a justified reputation as a corner of paradise.

Of more interest to most readers here, the move puts me back within decent viewing distance of launches from Vandenberg Air Force Base.

Alas, relentless California coastal summer fog rendered the late-August launch of a Delta IV Heavy invisible. As the seasons turn, bringing Indian summer to the coast, I have better hopes for the upcoming Falcon 9 launch, postponed from midmonth and now scheduled for September 29th.

For those who live near the West Coast, or simply want to keep track of launch schedules, here is a Web page listing scheduled Vandenberg launches.

This launch schedule also provides some important - and frustrating - lessons about the practicalities of space flight.

The most important of these lessons is that space launches are rare. Not counting ICBM test flights (one pending, and one I slept through and missed a couple of nights ago), three launches are scheduled between now and March. Throw in the late-August Delta IV launch and it comes to four launches over an eight-month period.

This is surely not an 'efficient' usage of facilities and resources. A space launch center must be broadly comparable to a large airport. The vehicles it handles are about the same size as jetliners, and at least as demanding. They must be prepped, serviced, and sent on their way, using a lot of specialized equipment, and - even more expensive - teams of human expertise.

If a major airport handled one flight every other month ... airline tickets would not be cheap.

In fairness, Vandenberg is not the most heavily used launch center. It is used for polar-orbit launches, particularly for spy satellites, though also for some types of geosats for which maximum coverage of the Earth's surface is important. Polar-orbit launches cannot benefit significantly from Earth's rotation, so they are avoided unless specifically called for.

But sometimes they are called for, meaning that all traffic cannot be consolidated to a single launch site. Worldwide there have been rather less than 100 launches in each of the last few years -74 in 2010, 84 in 2011, 78 last year, and 52 so far this year.

This includes a handful of failures each year; out of 286 attempts this decade, 18 were failures, a 6 percent failure rate. This is, I believe, a somewhat higher failure rate than in the last couple of decades - at least in part, I'd guess, because of more new and inexperienced players in the game.

But any way you cut it, space launches are not an everyday event - more like one or two per week, worldwide.

The problem of low traffic volume does not just drive up the cost of launching rockets. Production of any one given type is only a dozen or so per year - up to 19, in 2011 for the Russian workhorse Soyuz (R-7) and China's Chang Zheng. Individual Western booster types rarely see more than half a dozen launches per year. Forget production-line efficiencies.

This traffic volume also puts paid to reusable launch vehicles. Quite apart from technical challenges, there just isn't the traffic to keep them busy. (And since payloads vary widely, you'd really need a stable of types, just as with expendables.)

In fact, given the traffic level, a stable of expendables is the most cost-effective approach. For any given individual payload they are far less expensive than a reusable vehicle that has to not only get the payload up, but then get itself back down.

Yes, this is a dead horse I have beaten here many times before, and will no doubt beat again. But actually living where I can watch space launches brings some immediacy to the topic.

On the bright side, we are sending some 80-odd missions a year into orbit and beyond. More than that, in fact, since many launches carry multiple satellites. As also noted here before, we have sent missions to every major planet in the Solar System, and a good many other objects.

And I am looking forward to Sunday morning, when that Falcon 9 is scheduled to go up. With a little bit of luck the sky will be clear.


The image, via Flickr, shows a Delta IV Medium launch from Vandenberg, last year.