Instead, NASA researchers now think the debris trail was caused by the collision of two asteroids rather than the usual ice melting off a comet. With characteristic understatement, NASA described the collision as “energetic.” Perhaps a more appropriate word is “violent,” as the estimated impact speed of a collision of this nature is some 11,000 miles per hour, or five times the velocity of a rifle round.
However you want to describe it, if you look closely at the image above you can see that the nucleus of the debris is oddly outside the debris halo, indicating that some kind of smash-up did occur. Of course, there’s no way NASA can be absolutely sure of this. We have our own theory about what Hubble is tracking out there, and it’s from far, far beyond the Asteroid Belt.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.