*DIAMONDS CAME FROM A LONG-LOST PLANET*

PARIS : A car sized asteroid that exploded in Earth's atmosphere in 2008, raining down diamond-bearing rocks-

Was a fragment of a Solar System planet that existed billions of years ago, researchers said on Tuesday.

The parent planet was about as large as Mars or Mercury, and was formed in our Solar System's first 10 million years being shattered to pieces in collision with other space rocks, a European team reported.

Using high-definition microscopy, the researchers measured the composition of diamonds locked up in rocks left scattered in the Nubian desert of Northern Sudan after an asteroid dubbed 2008 TC3 crashed into Earth.

They concluded the precious stones must have formed at pressures that could only have existed on long lost Mars to Mercury-sized planet.

These are the smallest two planets in our Solar System, which was forged some some 4.6 billion years ago.

The measurements provide ''the first compelling evidence for such a large body that has since disappeared.'' the research team wrote in a paper published in the journal Nature communications. [AFP]