Space telescope gets snap of `young planet'

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The Independent Online
ON the photograph it looks like a faint smudge, but to astronomers it is "unbelievably exciting": the first photograph of a planet outside our solar system. Its discovery could, they say, change our views of how planets form and lead to the discovery of life-bearing planets - though there are no signs of it on this one.

The picture, taken by the Hubble Space Telescope, is "a major, unprecedented observation," said Alan Boss, an astrophysicist at the Carnegie Institution of Washington. At the centre is the bright glow of a pair of stars circling each other in a binary system. On the bottom left is the planet itself, which appears to have been catapulted 200 billion km (130 billion miles) into space from the pair of stars where it formed.

Like the stars, it is in the first flushes of youth - a "proto-planet". The planet and stars lie 450 light years from Earth, in the constellation of Taurus in a region where stars are still forming. Though it is in the same postcode as us, galactically speaking, the prospects that it holds any form of life we could recognise are remote.

It is two to three times bigger than the largest planet in our solar system, Jupiter, which is 318 times more massive than Earth. It is also far from its suns, compared to us: the most distant planet in our solar system, Pluto, lies only 6 billion km away from the Sun at its most distant.

Scientists have detected more than 10 such "extrasolar" planets like this before, but this is the first time they have had a picture of one.

But those have been detected by the effect they have on the stars they orbit: because they are so massive, they produce a "wobble" in the star's motion, which sensitive instruments can detect.

A team at the US space agency Nasa, which released the pictures yesterday, said the sighting "challenges conventional theories about the birth and evolution of planets and offers new insights into the formation of the solar system."

Previously, extrasolar planets that have been detected were orbiting middle-aged stars. "The Hubble observation is the first peek at a young planet," said Nasa.