NASA曝新计划：捕获小行星

DAVID GREENE, HOST: OK, President Obama released a new budget this week. It lays out the White House spending plan for the entire federal government. Much of the document is mind-numbing, endless pages of spreadsheets and numbers. But there is one section on NASA that reads more like the premise for a Hollywood blockbuster.

NPR's Geoff Brumfiel reports on plans to lasso an asteroid.

(SOUNDBITE OF A BEEP)

CHARLES BOLDEN: Welcome to this media teleconference about NASA's fiscal year 2014 budget proposal.

GEOFF BRUMFIEL, BYLINE: The mind can wander during long teleconferences about budgets. So when NASA administrator Charles Bolden announced the big plan, I almost missed it.

BOLDEN: NASA is using game-changing technologies advanced by the administration to develop a first-ever mission to identify, capture and retrieve an asteroid.

BRUMFIEL: What?

BOLDEN: A first ever mission to identify, capture and retrieve an asteroid.

BRUMFIEL: Sure enough, NASA's $17.7 billion budget includes plans to capture a small asteroid, drag it to the Moon and put it in orbit. Within a decade, astronauts could visit and study it up close.

Louis Friedman is director emeritus of the Planetary Society.

LOUIS FRIEDMAN: The very idea of lassoing an object and towing it to Earth orbit sounds pretty preposterous when you first think of it.

BRUMFIEL: But it's not. Last year, Friedman headed a committee of academics who took a serious look.

FRIEDMAN: Not only was this pretty feasible - at least at the early look of it - but it was the only way that humans would actually get out beyond the Moon in the next couple of decades.

BRUMFIEL: NASA originally wanted to send astronauts into deep space to study an asteroid in its natural habitat. But the rockets currently under development just aren't powerful enough. Friedman says that this alternative is more realistic.

FRIEDMAN: If you have to cross a river, and the stepping stone to try and jump to is beyond your capability, you might go over someplace and roll down a Boulder and try to get it into the river someplace where you can reach it.

BRUMFIEL: Here's the plan: NASA will use telescopes on Earth to track down a small asteroid passing by. Those telescopes, by the way, will also look for anything that might hit us. Once they've found a target asteroid, the agency will launch a robotic spacecraft to intercept it. In Friedman's study, the spacecraft has a huge inflatable cone on the front. When it reaches the asteroid the cone inflates, and traps the rock inside. Then it deflates.

FRIEDMAN: I call it shrink wrapping the asteroid.

BRUMFIEL: That process draws the asteroid to the spacecraft and secures it.

FRIEDMAN: And now all you have to do is steer your engines in the right direction to come back on the course that you want to.

BRUMFIEL: Not everyone is buying this bold new proposal, however. Jay Melosh is a researcher at Purdue University.

JAY MELOSH: It's not impossible but it's very difficult, and one could wonder about what advantage would there be in doing all that stuff.

BRUMFIEL: The goal of NASA is to get to Mars, he says. That requires solving really difficult problems, like protecting astronauts from the radiation in deep space.

MELOSH: And I think you'd kind of be wasting your resources on playing around with this little asteroid, while not facing up to the major problems.

BRUMFIEL: Louis Friedman doesn't deny that this is a less ambitious project, but he says it will get humans further out into space than they've ever been before.

FRIEDMAN: Well, it's not solving the long range interplanetary transit issues. But if we try to do all of that in one step, then you'll come back to your money question, so I think this is the compromise.

BRUMFIEL: Even this compromise won't be cheap. Estimates of the total cost of bringing the asteroid to the astronauts are currently around $2.6 billion.

Geoff Brumfiel, NPR News