Scientists have been discussing for several years how to prepare for such an event — however remote. European Space Agency spokesman Bernhard von Weyhe says experts from Europe, the U.S. and Russia are working on way to spot potential threats sooner and avert them. But don't expect a Hollywood-style mission to fly a nuclear bomb into space and blow up the asteroid, like the movie "Armageddon."
"It's a global challenge and we need to find a solution together," he said. "But one thing's for sure, the Bruce Willis 'Armageddon' method won't work."
Science Writer Malcolm Ritter in New York contributed to this report.