Nature‘s got a piece up under the headline Duelling visions stall NASA: A US plan to send humans to explore an asteroid is losing momentum.
Summary: President Obama proposes an asteroid as the next major destination for humans in space, but nobody at NASA’s convinced this is (a) feasible or (b) worthwhile.
Here’s the most pro-asteroid part of the article:
But Mark Sykes, president of the Planetary Science Institute in Tucson, Arizona, and chair of NASA’s Small Bodies Assessment Group, remains a big fan of asteroids. He notes that human explorers could search for resources such as water. Scientists could seek to understand the subtle pressure of light that causes asteroids to change their spin, and could retrieve samples for dating and chemical analysis that would offer a clearer picture of Solar System material than do meteorites, which, although they are pieces of asteroids, are altered during their fall through Earth’s atmosphere.
But all this could be done more cheaply with a robotic mission, says Sykes. Without a sustained drive towards something bigger — such as a human presence on Mars — even Sykes isn’t terribly excited. “You go to an asteroid, then what?” he says. “If it’s all performance art, that’s not much of a mission.”
“Search for resources such as water” has got to be the stupidest reason imaginable for going to an asteroid. As Bob Park put it a few years ago, “I told NASA that I would be happy to leave my garden hose out and they could come by and take all the water they want.”
Sykes is quite right that all of the listed reasons would be much better done with robots than people. You don’t send people into space to do science.
There’s one and only one reason for sending humans to any given destination in space: because it’d be awesome to send humans there.Is the intrinsic awesomeness of someone going to an asteroid worth the cost and risk? Then let’s send people there. If not, not.
The word “risk” there is a huge understatement, by the way:
Then there is the problem of just getting there. NASA is increasingly concerned about the radiation exposure and bone loss that astronauts might face during a long voyage outside Earth’s protective magnetosphere. “You get a bad solar storm and you’re toast,” says Mackwell.
As far as I can tell, having humans spend years in zero gravity being bombarded by radiation is virtually certain to ruin their physical health and lead to premature death.