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.