Asteroid With Comet-Like Tail Forces Scientists to Reconsider Theories

An active asteroid in our solar system's main asteroid belt between Mars and Jupiter, has a comet-like tail, a research says.

The asteroid, named 62412, is the first comet-like object seen in the Hygiea family of asteroids.

Researchers Scott Sheppard and Chadwick Trujillo from the Carnegie Institution of Washington discovered an unexpected tail on 62412, an object which had been known as a typical asteroid for over a decade.

"Until about ten years ago, it was pretty obvious what a comet was and what a comet wasn't, but that is all changing as we realise that not all of these objects show activity all of the time," Sheppard said.

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In the past, asteroids were thought to be mostly unchanging objects, but an improved ability to observe them has allowed scientists to discover tails and commas.

The team found that 62412 has a very fast rotation that is likely to shift material around its surface, some of which may be emitted to form the comet-like appearance.

The tail may be created directly from ejected material off the fast rotating nucleus, or from ice within the asteroid subliming into water vapour after being freshly exposed on the surface.

Sheppard and Trujillo will present their findings at the American Astronomical Society's Division for Planetary Science Meeting being held in Tucson, USA, November 9-14.