A handy little asteroid calculator
A little later this evening — 6:28 EST, to be precise — an asteroid the size of an aircraft carrier will drift past the Earth, missing us by about 202,000 miles. (That’s slightly closer than the moon, for reference, but still pretty far away.) Good news for us, but what if the asteroid had actually made contact?
Nothing good. Jay Melosh, an atmospheric scientist at Purdue, has created a nifty little “impact calculator” that lets you figure out the consequences of a large asteroid hitting the Earth. If the asteroid of the moment, YU55, were to enter the Earth’s atmosphere at 11 miles per second, it would burn up, and the remaining chunks would, on impact, create a crater four miles wide and 1,700 feet deep.
“Sixty miles away from the impact site the heat from the fireball would cause extensive first-degree burns,” the Purdue team notes. “The seismic shaking would knock down chimneys and the blast wave would shatter glass windows.” The asteroid could technically wipe out a city the size of Chicago, although the chances of hitting a city are pretty small. If it landed in the ocean, it’d create tsunami waves 60 feet high.
Fortunately, we probably don’t have to worry about another asteroid this size moseying near Earth until 2028. NASA’s Near Earth Object program has been tracking objects in our vicinity that are more than six-tenths of a mile in diameter — the dangerous ones, basically — and now claim to have discovered more than 90 percent of them. Of course, sometimes these objects can creep up pretty quickly: YU55 was only discovered in 2005, by the University of Arizona’s Spacewatch Project.