Nature:
Although it's possible to use a ground-based laser to move
space debris out of the way of satellites, the idea hasn't been
put into practice out of fear that the lasers could also be
used as antisatellite weapons. To alleviate that fear, James
Mason of NASA's Ames Research Center has proposed using a
ground-based laser whose power is high enough to nudge debris
out of the way but low enough to avoid harming spacecraft.
Nature's Jon Cartwright reports that Mason's idea
appears feasible—except, perhaps, for moving massive
pieces. Its harmlessness is in doubt, however. Nudging a
satellite off course could also constitute a hostile act.
