First earth-like planet seems to be volcanic wasteland

The first Earth-like planet spotted outside our solar system seems to be a volcanic wasteland.

The rocky planet CoRoT-7b was discovered circling a star some 480 light years from Earth. It is, however, a forbidding place and not likely to harbour life.

That's because it is so close to its star that temperatures might be above 2,200 Celsius on the surface lit by its star and as low as minus 210 Celsius on its dark side.

Now scientists led by University of Washington (UW) astronomer say that if CoRoT-7b's orbit is not almost perfectly circular, then the planet might also be undergoing fierce volcanic eruptions.

It could be even more volcanically active than Jupiter's moon Io, which has more than 400 volcanoes and is the most geologically active object in our solar system.

"If conditions are what we speculate, then CoRoT-7b could have multiple volcanoes going off continuously and magma flowing all over the surface," says Rory Barnes, UW postdoctoral researcher of astronomy and astrobiology.

Barnes and his colleagues suspect CoRoT-7b is subject to extreme volcanism partly because it is so close to its sun, the distance between the two being about 1.6 million miles (2.5 million kilometers). That's about 60 times closer than the Earth is to the sun.

Any planet where the surface is being remade at such a rate is a place nearly impossible for life to get a foothold, he says.

CoRoT-7b was discovered by a French-led team using the CoRoT - Convection, Rotation and Planetary Transits - satellite.

Rocky planets - Earth, Mercury, Venus and Mars - make up half the planets in our solar system. Rocky planets are considered better environments to support life than planets that are mainly gaseous, like the other half of the planets Jupiter, Saturn, Uranus and Neptune.

The next step to finding a planet that harbours life may have to wait until astronomers are better able to detect rocky planets that are farther from their stars, Barnes says.

Calculations about CoRoT-7b's orbit and probable volcanism were presented at the American Astronomical Society meeting in Washington, D.C. Jan 5.

Last updated on Jan 7^th, 2010 at 15:18 pm IST--IANS