NASA’s current asteroid-redirect mission plan calls for a robotic probe to capture a small asteroid (or one boulder from a large space rock) in deep space and tow it back to lunar orbit, where it would be visited eventually by astronauts. But another proposal advocated in an October 2014 editorial in the journal Nature would fly a crew directly to a near-Earth asteroid, or NEA, in its native orbit.
If the ultimate goal is a mission to Mars, a NEA in its native orbit provides more experience in operating long-duration missions in deep space, says the editorial's author, MIT professor Richard Binzel. NASA’s proposed asteroid redirect mission would not take crews much farther than they’ve already...
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