Word: asteroidal
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...good example of Japan's strategy of selective excellence is the Hayabusa space probe. Launched in May 2003, the robotic craft reached a 300 m by 700 m asteroid called Itokawa last month and set about mapping it. The mission calls for the probe to descend to the surface of this small asteroid next month and remove rock samples before starting the 2.5-year journey home. If successful, the Hayabusa mission will mark the first time material has been recovered from an asteroid in space and returned to Earth...
...mission involves other innovations. The Hayabusa ("falcon") spacecraft is powered not by a conventional liquid chemical rocket but by an ionized-xenon-gas engine, a propulsion system that is 10 times more efficient. Just as novel is a half-kilogram rover that Hayabusa will dispatch to roam the asteroid for several days. The robot, named Minerva, will use its miniature cameras and thermometers to send data back to the mothership. Since wheels are useless on such low-gravity surfaces, the coffee-can-sized machine will maneuver using an internal pendulum?a swinging weight that will let the bot hop about...
...This news was grist for the mills of the B612 Foundation (named after the fictional asteroid home of "The Little Prince," in Saint-Exupery's novel). The astronomers and scientists who founded B612 did so to alert Congress and the public to the menace of an asteroid strike and to lobby for a demonstration mission by 2015 that could show the feasibility of a controlled deflection of an object threatening to strike the Earth...
...letter sent last month to NASA Administrator Michael Griffin, former astronaut Rusty Schweickart, B612's chairman, called attention to the Apophis dilemma. He urged that a radio transponder, similar to those on commercial airliners, be landed on the asteroid so that astronomers might track its orbit precisely to determine if it will pass through a keyhole, and he requested that NASA quickly estimate the time required for both landing the transponder and a subsequent deflection mission that could alter the asteroid's orbit...
...rush? The Apophis deflection, should it become necessary, must take place before the 2029 close approach. Earlier than that, just a simple nudge, accomplished, say, by firing a heavy object at the asteroid, could change its course enough to miss the crucial but small keyhole. Any time after that approach, should Apophis pass through the keyhole, we could be in trouble. NASA scientist David Morrison explains: "After 2029, the deflection would have to be vigorous enough to miss not just a tiny keyhole but the much larger target of the Earth itself. And such a deflection is far beyond present...