Spacecraft Could Be Used To Deflect Killer Asteroids

An unmanned "tractor spacecraft" could eventually be used to drag an asteroid off course before it slams into Earth with catastrophic consequences, experts said Friday. NASA astronaut Edward Lu said Hollywood-style solutions such as detonating a nuclear bomb in outer space to destroy an oncoming asteroid could increase the chances of a hit on Earth. Speaking at the American Association for the Advancement of Science's annual meeting, Lu said the most viable tactic would be to use the gravitational pull of a spacecraft to alter the asteroid's trajectory. U.S. scientists are closely monitoring the progress of Apophis, which is scheduled to pass within about 32,000 kilometers (19,000 miles) of Earth in 2029. Experts have said previously it is possible that Apophis, which could obliterate a country the size of England if it struck, may change its orbit when it swings by Earth in 2029, putting it on a collision course with the planet when it is due to pass by again in 2036.