Asteroids have been the fodder for some⦠interesting science fiction blockbusters, but with the strike in Chelyabinsk, Russia this year, scientists say it's time to get serious. Two papers published in Nature -- one of the most prestigious academic journals -- suggest that asteroid strikes might be a bit more common in the coming years.
Current searches for asteroids are only for those that are at least 1 kilometer wide, but those are rocks big enough to end our civilization. Smaller bits -- those that are capable of devastating countries or cities -- slip through the cracks.
Former astronaut Edward Lu is prepared to help defend Earth with B612 -- a project with the goal of detecting much smaller threats from outer space. According to the project, there are a million "near-Earth asteroids large enough to substantially damage or destroy a major city." Equivalent to a massive minefield of nuclear warheads, this is not a threat we can simply ignore.
Impacts the size of the one that hit Chelyabinsk should be expected every one or two decades. To be sure, a good chunk of the Earth is uninhabited, and it's unlikely that any of these impacts will hit a major city, but with the stakes as high as they are, that's no longer a gamble we can afford to make.