If you think Superman's "faster than a speeding bullet," get a load of asteroid collisions: NASA says they're going 11,000 mph, five times the speed of a rifle bullet.
And the orbiting space telescope Hubble may have just photographed one of these cosmic accident scenes, detecting a pattern of dust and other debris that appears to form an "X," possibly the trail streaming from where two asteroids smashed together.
"Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never been seen before," reports the NASA online news service Science@NASA.
The Lincoln Near-Earth Asteroid Research or LINEAR sky survey first saw this Jan. 6, and Hubble shot images on Jan. 25 and 29, detecting the X-pattern. The remaining nucleus of the object has been designated P/2010 A2. It is thought to have a diameter of 460 feet.
A comet coming from outside the solar system jets a tail or trail of debris as it nears the sun and ice melts from its nucleus. But this object appears to orbit in the asteroid belt, where its "X"-shaped trail of debris could indicate an impact.
"If this interpretation is correct, two small and previously unknown asteroids recently collided, creating a shower of debris that is being swept back into a tail from the collision site by the pressure of sunlight," said David Jewitt of the University of California at Los Angeles.