It’s not just the big asteroids we have to watch out for?the little rocks can be dangerous too. They’re hundreds of them out there and they’re hard to spot, but NASA has decided it had better start searching for them.
Robert Roy Britt writes in Space.com that it will cost at least $236 million to add a search for small asteroids to their ongoing Near Earth Object (NEO) detection program. An asteroid twice the size of a football field or bigger hits the Earth about every 15,000 to 20,000 years, according to NASA’s Donald Yeomans. Impacts from smaller space rocks cause only regional problems, but these could be severe, and there are so many more of them that this kind of impact is much more likely to occur.