A Cosmic Comet Breakup

CreditCreditDavid Jewitt/UCLA/NASA-ESA

Call it a heavenly breakup.

A comet came apart at the seams as the Hubble Space Telescope watched last January.

Comet 332P/Ikeya-Murakami, as it is known, was discovered six years ago by a pair of Japanese amateur astronomers Kaoru Ikeya and Shigeki Murakami.

It was coming around for another pass by the sun last winter and still out past Mars when Hubble spotted it 150 million miles from the sun. It was already in two dozen pieces spread over 3,000 miles of space and slowly drifting farther apart.

As the comet fell sunward, heat from the sun vaporized parts of its icy surface, astronomers say, causing jets to erupt and pieces to break off. The main piece is what remains of the comet nucleus, about 1,600 feet across, the astronomers, led by David Jewitt of U.C.L.A., said. Over three days starting Jan. 26 Dr. Jewitt and his colleagues used Hubble to track the fragments as they spread. If these breakups continue on future orbits of the sun, they said, the comet will be all gone in 150 years.