Astrogator's Logs

New Words, New Worlds
Artist, Heather Oliver             

Small Bricks, but Bricks All the Same

My dreams of space exploration never wane, no matter how dismal its prospects look. So I’ll be one of the hopeless (hopeful?) romantics giving presentations at the 100-Year Starship Symposium, organized by DARPA (in Orlando… at least it’s not Las Vegas).

On other fronts, I moderated and participated in a discussion of Lavie Tidhar’s new novel, Osama, which just went live on SF Signal. And Rose Lemberg will include my two Bull Spec poems (Spacetime Geodesics and Night Patrol) in her anthology of feminist speculative poetry, The Moment of Change from Aqueduct Press.

Now if only my neuroblastoma lines would behave…

Cool Cat is by Ali Spagnola

22 Responses to “Small Bricks, but Bricks All the Same”

  1. Astronist says:

    So far as I can see after browsing your earlier posts, your pessimism about the prospects for space exploration alluded to above is set off from my own optimism by two factors: you do not share my sense that private-sector enterprises have an essential contribution to make, and you do not share my understanding that the large majority of our descendants will live in totally artificial city-sized orbiting space colonies. So where I see falling costs and rising traffic levels in the service of large-scale tourism and energy markets, you see persistent high costs on government vehicles, and where I see large populations living permanently in space, you see only planet surface-dwellers.

    This is not to say that either of us is right or wrong — I’m just trying to pinpoint the reason for the difference of opinion.

    Enjoy the symposium!

    Oxford, UK

  2. Athena says:

    I don’t necessarily see the descendants of humanity exclusively as planet-dwellers, but I think you underestimate the problems of an orbiting space colony by several orders of magnitude. Also, although I see private sector involvement, I think it will come late(r) and only when assured of quick profit — as was the case with the Internet.

  3. Caliban says:

    That’s great news about Rose taking your poem. She is also taking my poem, “Towards a Feminist Algebra.” Congratulations!

    *tips celebratory glass of internet champagne*

  4. Athena says:

    Feminist Algebra deserves to be on many anthologies! Togetherness, eh? *smile*

  5. Astronist says:

    Athena, thanks. My point is not that particular things are easy or difficult to do — clearly, engineering and social change are not armchair topics; one has to actually try things to see whether they work or not and what the real-world problems and solutions are. I’m just trying to identify the broad logic of development as regards interstellar travel.

    The concept of fast interstellar crossings between Earth-like planets within a human lifetime, given the likely rarity of such worlds, requires speeds in excess of 90% of c, hence a breakthrough in propulsion, plus a breakthrough in reduction of energy costs. At present these seem unlikely (tho proponents of so-called vacuum energy might disagree).

    Therefore human interstellar expansion depends upon relatively slow worldships. These are effectively interstellar space colonies. Therefore the prior necessary step is interplanetary space colonies. But given the fact that the resource base for these is greater than that for planetary colonisation within the Solar System (measured in terms of habitable surface area which can be constructed), a civilisation capable of building passenger-carrying interstellar ships would appear to be one dominated by space-dwelling populations, not planet-dwelling ones. This in my judgement is a precondition for such flights to occur.

    How long such a population shift would take, neither of us knows — maybe a handful of centuries, maybe 100,000 years. You would clearly lean towards a longer period. I offered a shorter timescale to the BIS symposium, tailoring the message to the audience, I suppose, tho I also touched upon other scenarios, including one in which propulsion and in-space habitation never converge sufficiently to allow interstellar flight to take place at all. Prediction is hard, especially of the future.

    So perhaps we can be content to agree for the present that a society capable of launching passenger-carrying starships may take somewhere between 500 and 100,000 years to develop? (Assuming that it does not collapse somewhere along the way.) Longer than 100 years, in any case!

    Best wishes,

  6. Martin J Sallberg says:

    Useful Casimir effect for cheap spacelaunches.
    The Casimir effect is traditionally demonstrated by placing two thin parallel plates mere micrometers apart in a vacuum and letting them slam together. The effect is due to vacuum energy. It can in principle be used to modify the vacuum for cheap spacelaunches and efficient space travel, but that requires preventing the plates from slamming together, so that the Casimir effect remains. That can be done by repulsive magnetic fields or by mechanically holding the plates in the edges (only in the edges, to keep the space between them). Another possibility is to abandon the parallel plates altogether and use microchannels or other microscopic holes instead. Anyone is free to build it, I am not going to claim any patent or money.

  7. Athena says:

    Well, Stephen, I didn’t name the symposium, DARPA did!

    From reading my Making Aliens series you know that I don’t think there will be exotic means of propulsion any time soon, if ever. So yes, slow arkships will be the primary vehicle. But you seem to conflate “space-dwelling” with “space-adapted” which is the crux of the problem for such ships: they will require aeons of suboptimal living not only for humans but for the entire biosphere within them. Living both on other planets and in arkships (whether stationary or traveling to a destination) present us with equally enormous sets of problems.

    Martin, it’s unclear to me (and anyone else) that you can use the Casimir effect for large-scale items like starships.

  8. Astronist says:

    Yes; I listed some of those problems in my BIS talk: creating a closed-cycle ecological life-support system; adapting agriculture to a compact, high-energy-efficiency mode; installing radiation shielding (not necessary, however, when the colony exceeds a certain size and hence outer wall thickness, as noted by Martin and Bond in 1984); the politics, economics, psychology and criminology of relatively small communities in a confined space (tho a city on Earth is also fairly confined, and developments in virtual reality entertainments may make the lack of a recreational hinterland irrelevant); obviously all the aspects of human reproductive biology (genetic stability, population control, male and female fertility, embryo development in an inevitably imperfect simulation of our ancestral terrestrial environment); the division of skills and labour in a relatively small workforce to enable production of all the infrastructure components and consumer products required by civilisation (which again will be conditioned by future developments in computing).

    I drew the logical conclusion that this would not be all set up for a unique government starship mission, but on the contrary could only arise through a long process of gradual evolution of an extraterrestrial population and economy, over a large number of human lifetimes.

    As you say, our descendants would need to be space-adapted, and you mention the two elements which could bring this about: plenty of time to adapt, and the creation of new, artificial environments which are not optimal for a species evolved on Earth, and which will therefore stimulate evolution towards adaptation to those new environments. Clearly, this evolution will be a complex synthesis of cultural/technological adaptive changes, both market-driven and government-driven, with unplanned/unintended ones. I do not pretend to be able to predict how long this might take; I merely point out that the extended colonisation of space within our own Solar System is an essential precondition for sending passenger-carrying ships to the stars! (Unless a fast, near-light-speed dash to a twin of Earth is possible, which we both doubt.)

    Best wishes,

    Oxford, UK

  9. Caliban says:

    The problem I see with your scenario, Stephen, is unfortunately a key one: what drives so many people into space?

    Right now manned space flight is primarily driven by national prestige; the “science” derived from manned space flight is, sadly, minimal. Grand plans for drug development, new manufacturing technologies, etc., have so far come to naught. But without a huge whopping carrot to lead people into space (or a stick forcing them, like environmental catastrophe, but at that point I suspect it’d be too late), why would we develop all these space colonies?

    It’s not that I *want* humanity to remain Earthbound, but mass migrations of the kind you describe are driven by *something*.

  10. Astronist says:

    Hi, Caliban. I think the most realistic scenario is one of a rather small number of Earth-born people settling space, and extraterrestrial populations growing from that small founder population (as described by John S. Lewis, Mining the Sky, p.236-239). Since they will have opportunities for growth many orders of magnitude greater than those of their stay-at-home cousins, over a long period they could grow to predominate in terms of population size and cultural, political and economic power.

    Certainly, the first 50 years of manned spaceflight have been almost entirely monopolised by government specialists in the cause of national prestige. But there are indications that the next 50 years may belong more to commercial flights in the service of mass markets for leisure travel (space tourism), commercial research (which is at present extremely difficult) and perhaps also space solar power. I would argue that such a reorganisation of the spaceflight industry is a necessary intermediate step before space colonisation can begin.


  11. Caliban says:

    I haven’t read Mr. Lewis’ book, so it’s possible that a steely-eyed cost/benefit analysis would show that colonization of space is even remotely sustainable. And I’d like to believe it’s true.

    But you still haven’t answered my fundamental question: what is going to lure people into space? “Opportunities for growth” is so vague it sounds more like a pitch to buy swampland in Florida than a reason to colonize space. (Why not the bottom of the ocean? Why not Antarctica? Also plenty of opportunities for growth, more resources close at hand, not nearly as expensive to reach.)

    When Europeans moved to the New World, for example, they had readily available land to grow food on, animals to hunt, forests with which to build houses. They had easy access to minerals, furs, and crops with which to trade with Europe. Almost none of that holds in space. Minerals, possibly, but since I have a good idea how much energy it takes to chase around in space I find it very hard to believe mining asteroids will actually be profitable. Which is a shame, really.

    As to your “reorganization” of the spaceflight industry, also not convincing. A few millionaire tourists is not enough to fund an entire industry; commercial research into… what? I’ve not heard of any industry wishing loudly it could do research on the space station and not be allowed to; and finally space solar power is highly unlikely to be financially viable–even on Earth it takes years to amortize the costs and that’s without having to lift it up a gravity well.

    A much more llikely scenario–though by no means guaranteed–is robotic missions. Robotic missions have been far mroe successful than manned spaceflight, by almost any measure. They are cheaper and more patient and there are fewer tears if they fail–or if we leave them to die on Mars. If we continue a foothold into space, it will be not through people “settling” space but almost exclusively with robotic probes and tools.

  12. Astronist says:

    Caliban, I answered your question “what drives so many people into space?” by pointing out that it need not necessarily be many people at all.

    Now you seem to be asking what will lure anybody at all into space. I suggest you ask them; I am sure you can think of plenty of people who are being lured into space one way or another — including the owner of this blog who is patiently tolerating our exchanges!

    A few millionaire tourists is not enough to fund an entire industry, granted. So how does one create a new industry? Does one create a mass market at low unit cost in a single leap, or must one pass through a long period of gradually increasing traffic, falling unit costs, increasing reliability and widening customer base? If the latter, then the current situation of occasional super-rich space travellers is a necessary intermediate stage, just as it was in air travel.

    Since you appear not to think that the resources of space can be accessed economically, you will clearly not be convinced by any demonstration that they dwarf those on Earth by many orders of magnitude. No doubt, 400 million years ago, few fish thought that life on land was remotely appealing or even possible!


  13. Athena says:

    Here’s what the owner of this blog thinks: I haven’t been lured to the concept — I’m more like a fossil who never let go of the vision even though I can see its enormous problems all too clearly.

    Crewed space exploration is extremely hard, because space is fundamentally hostile to us (as are the oceans). Unlike fish, we know this but, like fish, we cannot live in an environment to which we aren’t geared. I for one do not think private entrepreneurship will be the fuel that drives such ventures. I also think that it will take a very long-term approach (a problem with humans) and we have to be prepared for brutal losses. Past expeditions on Earth failed routinely, as did settlement attempts. This won’t be different in this respect except for scale.

  14. Caliban says:

    I would *love* for us to go into space, to colonize and to travel to the stars. I write SF and even space opera, so I have some emotional investment in this. I am certainly not someone who thinks we should “solve our problems on Earth first.” (No one has accused me of this, but I just want to be clear.)

    But as a physicist, I’m used to taking a cold-eyed look. And I think it’s quite reasonable to ask the hard, economic question of what takes people into space. Quoting “vast resources” is, frankly, a cop-out. In many place there are water shortages, but people do not ship ice from Antarctica even though there are vast reserves of fresh water there; and people seldom extract fresh water from sea water because it is so economically disadvantageous.

    On the other gold is a sufficiently valuable commodity that it is economically viable to dig deep into the earth to mine it, or in the case of the famed ’49’ers of California history, to move across the country. And there may be *some* resource in space that is sufficiently valuable to make it worth going into space. But I don’t know what it is and it’s pretty clear you don’t know what it is. You’re sure there is *something.* But my reading of history is that “vast resources” is not always enough.

    As for your fish metaphor, there are clear advantages to being on land. Oxygen, a key ingredient to life, is easier to obtain; early adopters escaped from predators. To me, that’s much more precise and persuasive than mumbling about “vast orders of magnitude” of resources.

    Look, I think it’s reasonable, even imperative to think about utilization and colonization of space. (See my first paragraph above.) I also think it’s reasonable to ask hard, difficult questions, even if they make you uncomfortable. So I’m not going to let bland, fuzzy statements just pass by, no matter how well intended or how nice they sound. And, by the way, attacking me as a stick-in-the-mud (or ocean, I guess) is not a substitute for a substantive argument.

  15. Walden2 says:

    Best of luck at the conference, Athena! So glad you and Paul Gilster will get to meet in person and so sorry I cannot join both of you. At least Cape Canaveral is not too far away and Seaworld was more enjoyable than I thought it would be.

    As for humans living in space, I too am leery of how well and how much the private sector can actually make this happen. I do not question their intent or ambition so much as whether they will ever get enough funding and resources to make this happen.

    Plus, if you will pardon my political paranoia mode here, the people in charge of everyone else would probably prefer not to have the masses start leaving their areas of control and setting up elsewhere to make their own power bases. Unless they want to get rid of any dissedents, but there are much cheaper and easier ways to deal with those elements.

    Still, I hold a hope that at least some groups some day will get off Earth and form their own societies. Because no matter how hard those in power try to keep the masses in line, some will always defy them. See the SF novel We.

  16. Athena says:

    Thanks, Larry! I look forward to meeting Paul in person, indeed.

    I’m totally with you about the potential problems of the private sector in connection with space ventures. I also agree that splinter groups are likelier to launch starships (though they’ll need to number rich members… which often means some kind of fringe cult.. which in turn means that spacefarers may not be people we’d like to meet or know.)

  17. Astronist says:

    Caliban, thanks. On the question of resources, let’s start with energy. The world is quite interested in finding a low-pollution, long-term sustainable, source of industrial energy. Since you are a physicist, I don’t need to remind you that, while our current power consumption stands in the region of 15 TW, the output of the Sun is 380 trillion TW, almost all of which requires space infrastructure to access and use. The main reason why this is uneconomic at present is the high cost of access to space, which is set to change when fully reusable spaceplanes such as Reaction Engines’ Skylon, currently under development in the UK with several million pounds of both government and private investors’ money, come into service in a decade or two’s time.

    The next question is of material resources. While Mars is an obvious target of possible future colonisation, any sustainable Earth-Mars transport infrastructure will need to access asteroids which orbit between these planets for in-space refuelling (including also the asteroid-like Martian moons), and that could lead eventually to construction of free-orbiting space colonies. If our species makes that leap (which may or may not actually happen), then the quantity of asteroidal material available in the Main Belt, of about one-twentieth of a lunar mass, consisting of an industrially useful mixture of metals, rocks and ices, is sufficient to construct colonies capable of supporting a human population an estimated one million times greater than possible on planet Earth alone, due to the fact that a rotating space colony of the type proposed by Gerard O’Neill offers surface area with gravity about a million times more mass-efficiently than a planetary body.

    I hope this clears up your problems with my statements.

    Athena, thanks, and I would never ever dream of comparing you with a fossil!


  18. Athena says:

    Stephen and Calvin — this discussion can continue indefinitely, but I recommend we leave it now, as it has entered the repetition stage.

  19. Walden2 says:

    How was the Symposium, Athena? I cannot wait to read your take on it when you get the chance. Are we any closer to reaching Alpha Centauri now? :^)

  20. Athena says:

    I defintely plan to express some thoughts on it, Larry. Briefly, though: the explicit goal of the 100-Year Starship program is not to build one, but (sigh) to think how we might build one. So we are not even close to reaching Proxima Centauri, let alone the more remote Alpha.

  21. Walden2 says:

    Oh, I didn’t think they had any actual starship plans or sheet metal ready to go, but I suppose it was better than nothing, especially in these times.

    BTW, you are quoted in this article, congrats!

  22. Athena says:

    True about the starships! Some of the comments she chose to include in that article were off-the-cuff… I had no idea she would use them. The ones quoted from the talk are more thought-out.