Per Ardua ad Astra
I'm starting to think that the only things I agree with my President about are war and tax cuts. Last week's proposal for a return trip to the Moon by 2015 and subsequent manned missions to Mars was of a piece with so much Bushism: pointless, or positively harmful, festivals of bureaucracy paid for out of public funds. There were in fact two of these horrors last week — this one, and the proposal to spend tax revenues on programs to encourage people to get married. The week before, it was a scheme to hand out green cards, together with full access to government services, to illegal immigrants. The week before that, … Oh, I forget.
The Bush proposal isn't all bad. We are going to dump the shuttle, and bail out of the International Space Station with as much haste as is decent — both decisions long overdue. The notion that our government should be paying to put people into space, though, remains. Given that, as the excellent UPI Science News report by Frank Sietzen and Keith Cowing says:
In the 1960s, America was not the risk-adverse society it had since become. NASA could make mistakes back then, pick itself up and move on. Indeed, people expected the agency to do so. Today, such bravura is no longer possible.
The cost of such adventures, per pound of human flesh in space, is going to increase without limit.
I am a big fan of space exploration, but cannot see any point in government programs to send human beings out there. That is just not necessary for any national purpose. I feel sure that by the end of this century the Solar System will be teeming with human space travelers; I just don't want any of that funded from my tax dollars.
What kind of space program would I like to see? Well, I think that first of all, I'd distinguish between the necessay and the cool: between things we must do in space and things it would be nice to do.
The things we must do are all military. The main one is, protection of our assets in orbit. When a US Special Forces scout in the Hindu Kush gets down from his mule, unpacks his laptop, takes a GPS reading and calls in an air strike on an Al Qaeda camp in the next valley, he needs to know that GPS satellite is in orbit and functioning. If it is, then he is the Angel of Death. If it isn't, he's just a guy with a mule and a game of solitaire. This is important. Similarly with spy satellites and military-communication satellites. This is vital to our national defenses, and it's government business. Whatever we decide to spend on space rockets, satellites, and space research, this has the first claim. So far as I know, none of it requires any human beings in space.
Nor does missile defense. I confess to being somewhat less than passionate about missile defense. It all seems to me a bit like anti-submarine warfare. We have had close to a century of R&D on that, and I am reliably informed that when the US Navy conducts exercises in submarine detection, those exercises still occasionally end with the "hunted" sub surfacing impudently well within torpedo range of the hunters. Face it, the odd missile, like the odd sub, will always get through. If you accept, as I certainly do, that losing two cities is much preferable to a nation-crippling loss of two hundred cities, then missile defense research is worth while; but I wouldn't throw half the defense R&D budget at it. The best defense against nationwide destruction remains good old-fashioned deterrence.
It is possible to think of other space-based military threats. Orbiting mirrors, focusing the sun's heat, could fry slabs of enemy territory. Large rocks hurled at the Earth from space (or from the Moon, as in one of Robert A. Heinlein's stories) could be as destructive as nuclear weapons, without all the nasty radiation … and so on. We need to think about these next-level threats, but we don't need to spend money on them yet.
That's pretty much it for the necessary. Everything else is just cool. The cool can be further subdivided into showbiz and science.
Space showbiz is just starting up, in the form of space tourism. I think this is going to be a big thing in this new century. Two tourists have already gone up, and two more are waiting on line. The past quarter-century of neoliberal economics has spawned a huge, world-wide class of billionaires to whom the cost of going into orbit — $20m or so — is no problem. Private enterprise is very nearly ready to take up this particular challenge. Space Adventures of Arlington, Va. will sign you up for a sub-orbital flight on whichever private-enterprise firm gets the equipment working first. The cost is a mere $100,000, and they are taking deposits. The movie and media companies will be right behind the tourists. I think this whole side of space development can be left to the private sector.
So, in theory, could science. Organized enthusiast groups, together with universities, could do great things. I confess I find my fiscal-conservative principles weakening here, though. I am a huge fan of space science, and I can't say I mind the thought of government helping out with the expenses.
However, I would exclude manned space flight from that. It's just too expensive, with too little scientific return for the buck. What we mostly learn when we send human beings into space is the effect that space travel has on human beings. That is mildly interesting, but it can't compare to the orders-of-magnitude increase in sheer knowledge brought to us by unmanned craft like the Voyagers, and instruments like the Hubble telescope. (Yes, I know Hubble needs manual servicing. For the cost of that servicing, though, I bet you could put up a replacement Hubble every five years. A shuttle flight costs half a billion dollars.) A mere forty years ago, our best images of Mars were of a fuzzy pink blob with some splotches of white and brown. Now we have detailed maps. This is real science, this is really worth doing.
Here is my wish list for pure-science space research.
- Solar-system exploration. Robot exploration of the solar system — planets, moons, comets, asteroids, and the Sun itself — has, as I said, yielded vast increases in our knowledge. There is much more to be done. The four major moons of Jupiter deserve a half-dozen missions each just by themselves. Pluto has not yet been imaged. And we know there is other stuff out there at Pluto range and beyond, though we don't know how much, or what it's made of.
- Space telescopes. The Hubble and James Webb telescopes should be just a start. With present technology, we could just about establish space-based optical interferometry telescopes. This would give us images of planets around nearby stars. We currently know only indirectly that such planets exist, from observing the movements of the parent stars. It would give us detailed images of the remote universe, too — clear pictures of the earliest galaxies that formed after the Big Bang. And all that is only to speak of optical imaging. Other parts of the electromagnetic spectrum — gamma and X-rays, ultraviolet and infrared, microwave and radio wavelengths — all have stories to tell. And that is only to speak of the electromagnetic spectrum. There are gravity waves, there are cosmic rays, there is the galactic magnetic field …
- SETI. (That is, the search for extraterrestrial intelligence.) Based on what we think we know about the formation of planets, the origins of life, and the evolution of advanced life forms, there ought to be plenty of other civilizations even just in our own galaxy; yet we have seen no trace of a sign of any. Why? This is one of the great scientific conundrums of our age. The only way to advance our understanding of it is relentless observation of the stars and planets of our own galaxy, and to a lesser degree of other galaxies. Most of this can be done from the surface of the Earth (and is being — you can participate yourself) but space-based observations would help.
- Propulsion. At present, the only way to get into space is on a rocket, which is to say a controlled bomb. The only way to get back is by friction — using air resistance to slow you from escape velocity to a normal air speed. Combustion and friction; that's all we have got. We are not short of ideas for alternative means of getting into space: scramjets, magnetic accelerators, space elevators — but none of them is even close to being practicable. This is a great pity, because once you are in space, getting around is rather easy, needs very little energy, and can be accomplished by lots of ingenious non-explosive technologies — ion drives, solar sails — that are cheap, safe and easy to build. Getting up there: huge problem, dangerous and expensive, combustion and friction. Moving around up there: cheap, easy, lots of options. It would be nice to reduce this unhappy differential, even if only a little.
All of that is thrilling stuff. All of it has the potential to turn up stunning surprises — dramatic shifts in the way we think about our place in the universe, sensational insights into the nature of matter, energy, gravity, that could transform our everyday lives.
None of it needs human beings in space. None of it needs colonies on the Moon or Mars. (Well, the Moon would be a lovely place to put certain kinds of observatories … but space will do.) And the worst news is, that expenditures on manned space flight suck away funds from all this worthwhile science.
Not only are there no scientific arguments for human beings in deep space, there are no arguments of any other kind, either.
- Economic? Mining the asteroids, beaming solar power down to earth? You could dredge up minerals from the deepest ocean trench, or from beneath the mile-deep Antarctic ice cap, ten thousand times more cheaply than you could get them from asteroids, and I have yet to see any solar-power proposal that would not be an environmental catastrophe. (All that energy has to go through the atmosphere.)
- Spinoffs? If you want to invent the nonstick frying pan, set a bunch of materials scientists to work on it. Give them a nice lab and lots of frying pans. Nobody needed to go into space for that.
- Romantic? I am as susceptible to the romance of space travel as anyone — more than most, probably, having spent most of my adolescence reading very little else but science fiction. I can't see that it is any business of government to cater to our romantic impulses, though, beyond a few low-cost ceremonies to keep our patriotism warm. Let's have a sense of proportion. In any case, what could be more romantic than the first evidences of a non-human civilization? A robot's-eye view of the oceans of Titan? Pictures from the beginning of time?
- Species survival? I'm fatalistic. In any case, people who talk about self-sustaining communities in space, or on other planets, underestimate the degree to which this planet is a vast support system for us, very difficult indeed to replicate at any scale. We are centuries away from self-sustaining space colonies. Forget about it.
- Political? Do I want the first person on Mars to be Chinese? Frankly, I couldn't care less. What difference would it have made to any American if the first man on the Moon had been a Russian?