France is ramping up activity ahead of December's launch of the COROT space telescope.

COROT, short for convection rotation and planetary transits, will search the skies for extra-solar planets, but unlike the hunting that has been done so far, COROT will be looking for rocky worlds, like Earth.

High above the Earth's obfuscating atmosphere, COROT will scan the stars, looking for a tell-tale dip in a star's brightness, indicative of a world passing in front of its parent star. It is capable of detecting a dimming of one part in 100,000, thanks to a light-trapping baffle system designed by the European Space Agency (ESA).

Most of the planets it finds will be so-called Hot Jupiters, gas giants that orbit very close to their parent star, like the majority of extra-solar worlds already identified. But because the telescope's view will not be impaired by the Earth's atmosphere, scientists are also expecting COROT to be able to identify much smaller rocky worlds.

Those planning to colonise an alien world should probably not get too excited, yet. COROT is most sensitive to planets orbiting very close to their parent star - closer even than Mercury is to the sun. However, none of these will be particularly hospitable worlds.

There is a chance, however, that the 'scope might spot a rocky planet in a tight orbit around a relatively cool red giant star. In this scenario, it might be possible for liquid water to exist on the hypothetical world's surface.

COROT has goals beyond planet hunting. While half its instruments search for alien worlds, the other half will be watching the surface of stars for sound waves, the stellar equivalent of seismic waves on Earth. Studying these subtle variations in a star's surface can give astronomers an insight into the internal workings of the star and should help unravel the details of stellar evolution.

ESA's COROT project scientist Malcolm Fridlund said: "Stellar physics is not a 'done deal'. In fact, we are really just beginning with it." ®