The use of a nuclear device to divert an asteroid on a collision course with Earth may not be as practical as some researchers had believed, according to a new report in today's Nature. "It's a lot more difficult to nudge these asteroids around than we had thought," said Erik Asphaug of UC Santa Cruz.
The problem is that many asteroids are, in effect, "rubble piles" left over from earlier collisions, and thus contain a relatively large volume of empty space. Computer modeling by Asphaug and researchers at JPL indicates that the space between the rubble would absorb much of the impact of a nuclear explosion so that the asteroid would be neither diverted nor destroyed.
Compiled by Times medical writer Thomas H. Maugh II