© NASA, ESA, D. Jewitt (UCLA)
Is this mystery object a comet or the result of an asteroid collision?
Is this mystery object a comet or the result of an asteroid collision?
The scattered debris that looks like a comet's tail is actually the result of two asteroids colliding nearly head-on at more than 11,000 miles per hour, scattering pieces in all directions, NASA announced earlier this week. The asteroid belt between Mars and Jupiter, where the collision occurred, contains the remains of many such events from the distant past, but this is first time that researchers have observed such debris so soon after a collision.
The object, called P/2010 A2, was first observed Jan. 6 by the Lincoln Near-Earth Asteroid Research program, and astronomers thought it was a comet. But images taken by Hubble on Jan. 25 and 29 show something far different.
Comets are icy bodies that fall into the inner solar system from distant reservoirs in the Kuiper Belt and Oort Cloud. As they warm up, they shed particles and water vapor that are pushed away from the comet in a smooth tail by solar pressure.
Comment: For a closer look at meteorites, asteroids and comets read Laura Knight-Jadczyk's Meteorites, Asteroids, and Comets: Damages, Disasters, Injuries, Deaths, and Very Close Calls.