Potentially life-supporting planet found

Researchers from the Geneva astronomical observatory have discovered a planet which they say is one of the best candidates for the ability to support life.

The planet – known as HD 85512 b – and its star – HD 85512 – are some 36 light years away from our solar system, according to an article published in the specialist magazine “Astronomy & Astrophysics”.

It is 3.6 times heavier than Earth and takes just 54 days to orbit its sun.

The article says the planet is at the inside limit of the “habitable zone”, defined as the distance close enough to its star to stop water freezing, and far enough to prevent it evaporating away.

Although the new planet is much closer to HD 85512 than Earth is to the sun, the conditions could nevertheless be met because the star is both smaller and cooler than our sun.

But a second article written by team leader Francesco Pepe and two of his colleagues says that other conditions must also be fulfilled. It would need a cloud coverage of 50 per cent to keep it cool enough for water to exist in liquid form.

The researchers have based their calculations on the assumption that the atmosphere is similar to that of Earth, with oxygen, carbon dioxide and nitrogen. They cannot say if life would be possible with a different atmosphere.

The planet was found using the Harps telescope at the European Southern Observatory in the Chilean Andes. The telescope has discovered about 100 of the more than 570 exoplanets – planets outside our solar system – so far known.

Back in 2007 Geneva researchers using Harps also discovered another exoplanet, Gliese 581 d, which is regarded as being another top candidate for supporting life.