Register for an account


Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.


Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.

The Sciences

#36: Astronomers Catch Asteroid Smashup

By Stephen OrnesDecember 16, 2010 6:00 AM


Sign up for our email newsletter for the latest science news

Last January a military telescope detected a bizarre object hurtling around the asteroid belt, leaving a long tail of dust. UCLA planetary scientist David Jewitt took one look and said, “Asteroid collision.” The millions of rocky objects orbiting between Mars and Jupiter probably collide all the time, but this is the first instance in which astronomers have seen direct evidence of an impact.

Jewitt and his colleagues watched the object and its fading, X-shaped tail for five months with the Hubble Space Telescope. The most likely scenario, he says, is that an asteroid just 10 or 20 feet wide struck the larger object, called P/2010 A2, which measures almost 400 feet across. (A less likely alternative is that P/2010 A2 is a solitary asteroid rotating so quickly that it flings off dust, producing the tail.) The speed and location of debris suggest that the crash happened in February or March 2009 at more than 11,000 miles per hour.

The find should help astronomers determine how much dust in the solar system originates in asteroid collisions; such impacts may also create fragments that reach Earth as small meteorites. It could also open a whole new field of study. Now that people know what an asteroid smashup looks like, “I’d be quite surprised if someone doesn’t find another one this year,” Jewitt says.

2 Free Articles Left

Want it all? Get unlimited access when you subscribe.


Already a subscriber? Register or Log In

Want unlimited access?

Subscribe today and save 70%


Already a subscriber? Register or Log In