Space telescope will seek new Earths

A spaceprobe blasted off today on the first mission to seek out new worlds like Earth which could hold life. UK scientists will work closely with Europe’s 80 million-euro (£50 million) Corot satellite which will scour thousands of other stars for small rocky planets.

Corot in operationBut unlike Star Trek, it will not fly to other stars to find them. Instead it will use a powerful telescope to watch the stars from its orbit around the Earth.

More than 200 other planets have already been detected beyond our own solar system. But they were giant gassy worlds like Jupiter.

Astronomers hope to find Earth-type planets more likely to harbour living organisms. If they are successful, it will be a vital step in the search for ET.

Corot, which was launched from Baikonur in Kazakhstan at 2.23pm UK time, will use a telescope with a 12-inch wide “shaving mirror” to monitor the light from 120,000 other stars in our Milky Way.

The robotic instrument, which is the size of a campervan, will watch five areas of the sky for six months at a time to check for changes in their appearance. Its sensitive “eye” – a sophisticated version of the chip inside a digital camera – will detect the tiniest fadings in the starlight which would reveal the presence of a small planet passing in front of it.

If, as expected, it identifies nearby stars as having planets just like Earth, it will have huge implications by indicating that life is widespread in the universe. It is also expected to spot many more of the bigger gas worlds – so-called “hot Jupiters”. Corot will be sensitive enough to observe starquakes too, caused by huge seismic disturbances inside the stars.

Professor Ian Roxburgh, of Queen Mary University, London, has ben involved with Corot since the mission was first planned in 1993. He told me today: “It was originally planned just to check what stars are made of but then someone pointed out we could use the same technique to look for other worlds.

“Corot will be able to spot much smaller planets than before, down to about twice the size of the Earth. Worlds that small must be rocky like our own and if they are at the right distance from their parent star then they could be habitable.”

Professor Roxburgh’s own special interest is in what stars are made of. He said: “From the wobbles in the light we will be able to map out the insides of the stars and learn more about stellar evolution. That will tell us more about out own sun.”

It was third time lucky for Corot, whose name stands for “Convection Rotation and planetary Transits”. Two previous lift-off attempts were called off. Yesterday’s launch, aboard an unmanned Soyuz rocket, lit up the night sky in Kazakhstan.

Corot’s orbit will carry it 515 miles above the Earth, flying from the north to the south pole, on a mission that is due to last two and a half years. Australia and Brazil are among international partners in the French-led mission, which will examine stars out to a distance of about three thousand light-years – our own cosmic neighbourhood. Picture: An ESA impression of Corot’s telescope in operation.