The end of the shuttle era

Because I’m an astrophysicist, people often seem to think I must be a big fan of the space shuttle.  As the shuttle program comes to an end, several people have asked me whether I’m sad about its going away.

Nope!  The end of the space shuttle (and its partner in codependency, the International Space Station) can’t come soon enough, as far as I’m concerned.

As far as science is concerned, the shuttle did one great thing: it put up and maintained the Hubble Space Telescope.  I’m grateful to it for that.  But as terrific as HST is, it doesn’t go a long way towards justifying the estimated $174 billion we’ve spent on the shuttle program.

That’s not really a fair criticism, because the shuttle program’s not primarily about science, and never has been.  (People often seem not to realize this, because anything to do with space sounds all sciencey.)  There are reasons for human space flight, but scientific research isn’t a good one: sending people up into space is not and never has been a cost-effective way to do science. So if we want to evaluate whether the shuttle program has been worthwhile, we should judge it based on other goals.

One goal people often mention is the intrinsic value of exploration of the unknown.  We should send people into space for the same reason that explorers charted new continents, went to the South Pole, explored Everest, etc.  I agree with this in principle, although it’s only fair to ask about the cost-benefit ratio in any particular instance.  But shuttle launches are not exploration in any sense of that word.

We sent people to the Moon in the 60s and 70s.  Since then, we’ve sent people repeatedly back and forth to low-Earth orbit.  Discussions in recent years about the possibility of going back to the Moon have made clear how far we are from being able to do that: it’d take years and cost huge amounts of money just to repeat what we did in the 60s.

Suppose that, after Columbus had returned to Portugal after reaching the Americas, Europeans did nothing but sail back and forth between the Portuguese mainland and the island of Berlenga, a few miles off the coast.  Suppose they did that for so long that they forgot how to sail across the ocean.  That’s pretty much the kind of “exploration” did when we came back from the Moon and spent the next four decades shuttling back and forth to low-earth orbit.

Actually, that’s not quite a fair comparison: Berlenga’s too far offshore.  I should have found an island closer to the Portuguese coast.

The other reason people often cite for supporting human space flight is that it inspires young people.  It’s always said that the Apollo missions inspired a whole generation of scientists, engineers, etc.  That’s before my time, and I haven’t studied the history, but  I’m prepared to stipulate that that’s true.

Has the shuttle had a similar effect? I don’t know of any data suggesting that it has, and I’d be very surprised if it did.  I’d be willing to bet that the Mars rovers Spirit and Opportunity have been far more inspiring to the public than the shuttle program, for less than the cost of a single shuttle launch.

(According to Wikipedia, the mission that landed Spirit and Opportunity cost less than a billion.  The cost of a shuttle launch is $174 billion / 134 launches, or $1.3 billion.  NASA says that “the average cost to launch a Space Shuttle is about $450 million per mission.”  I don’t know how this is calculated, but it clearly doesn’t include all costs.)

There’s an interesting debate to be had over whether human space flight is a worthwhile thing for the US government to be doing.  With the end of the shuttle program and the International Space Station, maybe we can actually have that debate.

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Ted Bunn

I am chair of the physics department at the University of Richmond. In addition to teaching a variety of undergraduate physics courses, I work on a variety of research projects in cosmology, the study of the origin, structure, and evolution of the Universe. University of Richmond undergraduates are involved in all aspects of this research. If you want to know more about my research, ask me!

9 thoughts on “The end of the shuttle era”

  1. Shut it down. In my more libertarian moments (most of them), I say eliminate NASA. But if it has to exist and spend money, why not focus on developing a space elevator? (Shut it down. Shut it down.) Or at least go to Mars…

  2. When has well reasoned cost-benefit analysis (regardless if how tangible or intangible those benefits are) really driven government spend? Lobbyists, special interests, “public opinion” and historical funding drive future funding.

    A big problem you don’t consider though is not just cost but value. What I mean is $174B is a lot of money. But did it need to cost that? Or half of that? Government spend has obscene bloat, and I wonder what the cost could have been given a different focus. Look at what the x prize achieved…. Obviously it is not a multi-year program with a similar focus as nasa, but is nasa worth the multiple?


  3. @Robert — You’ve managed to cultivate your libertarianism despite living in a democratic socialist paradise for so many years? Actually, maybe that helped you to maintain it: I believe that contrarianism is not entirely absent from the Dunlap genome.

    I’m not a libertarian: I do believe there are good outcomes that markets don’t provide and that government spending can. For instance, basic science research. (Yes, that belief is self-serving, since in my own small way I am the recipient of some of this spending.)

  4. @Derek–

    You’re quite right about the lamentable absence of cost-benefit reasoning in the government funding process. But that doesn’t mean that we as individuals shouldn’t use it in deciding whether to support or oppose particular programs. On the contrary, the less it’s happening in Washington, the more important it is that we try to do it, and then throw our political support around accordingly.

    I agree 100% that things like the X prize are a good model to consider as we try to find ways to achieve these goals more efficiently. In general, I’m very happy that the idea of private-sector support for space exploration is going mainstream. If Richard Branson et al. can push the human space flight envelope instead of NASA, that’s great as far as I’m concerned.

  5. Just to put things in perspective, I remember a figure from several years ago for US military spending: [queue sinister Dr. Evil voice] one million dollars per minute. That’s about 500 billion per year.

    On the whole, I agree with Ted’s post. Space exploration is interesting, but a) that’s not what has been going on in the last 40 years (or, to be sure, even before that: the last man on the Moon was the first scientist on the Moon (Harrison Schmitt)) and b) science in space is much cheaper when done by unmanned space probes.

    Looking to the future, I think it is good if NASA pulls out of space exploration; there is too big a danger that Mars will be colonised by members of the Tea Party. I would rather have Richard Branson behind things.

  6. I agree with you in not being sad about the end of the space shuttle era, for all the reasons you mention. But it’s worth pointing out that sailing back and forth between mainland Portugal and Berlenga probably isn’t a fair analogy.

    The reason is that the distance between two points isn’t the most relevant quantity for measuring the difficulty of a journey in space. A better metric might be the energy required to get there, since that roughly corresponds to the amount of rocket fuel needed.

    It’s true that the distance to the ISS is roughly 1/1000 of the distance to the moon. But remember that the Earth’s gravitational potential energy is nonlinear, falling like 1/distance. More importantly, just getting to the ISS isn’t enough; you also have to be going fast enough to maintain the orbit, which requires significant kinetic energy as well. By my calculation, boosting a single kilogram into the low-Earth orbit of the ISS requires 33 megajoules of energy. Lifting a kilogram to the gravitational midway point between the Earth and Moon requires about 62 megajoules. The difference between the two is more like a factor of two, not 1000.

    (Of course, the above analysis understates the difficulty in getting to the the moon and back, because it ignores both the fuel required to slow the craft for a safe landing on the lunar surface and the fuel for the return trip. There’s also a “fuel multiplier” effect: each kg of fuel required for the return trip requires still more fuel to get it to the moon in the first place, and so on. By contrast, the return trip home from the ISS is energetically easy: just reduce the orbital radius enough to catch a bit more of the earth’s atmosphere, and let atmospheric drag to the rest.)

  7. You’re right, of course, Matt. In my partial defense, I’ll point out that I wasn’t talking about the degree of difficulty but rather about the degree to which what we’re doing with the shuttle counts as “exploration.” I think it’s only exploration if you’re going to new and unfamiliar places, and low earth orbit doesn’t cut it.

  8. I know as a little kid the Space Shuttle program inspired me. Do we need a space program? YES! Why? It will help the economy, the new tech developed because of it, its part of our genetic make up to explore and it gives a great sense of pride as humans that we can actually do it!

    Plus I’d rather support a space program then an economy based on who has the bigger gun.

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