Italian helps find planet that could sustain life
HD 85512 B may have water given its position02 September, 17:22
''It looks big compared to planets in our solar system, but it's small for a gaseous planet,'' said Italian scientist Francesco Pepe, who is part of the team that discovered the planet, named HD 85512 B.
''This leads us to believe that it may be rocky, like the Earth. ''We still don't know if it has an atmosphere, or an ocean, but its distance from its star, and therefore its surface temperature, makes it compatible with the presence of water''. Pepe is part of a University of Geneva team led by Swiss astronomer Stephane Udry. The extrasolar planet is three and a half times as big as Earth.
It orbits the star HD 85512 approximately 36 light-years away, in the southern hemisphere constellation of Vela, whose Latin name means a ship's sail.
HD 85512 B is four times closer to its parent star than we are to the sun, so a year there only lasts as long as 54 Earth days. But because its star is smaller and about half as warm as the sun, the planet might have a reasonably temperate climate. ''If HD 85512 B has more than 50% cloud cover, it could be habitable,'' the scientists told Astronomy and Astrophysics magazine, noting that the estimated surface temperature is similar to temperatures in the South of France.
They used the High Accuracy Radial Velocity Planet Searcher, a high-precision spectrograph installed on the European Southern Observatory's 3.6m telescope at La Silla Observatory in Chile, to find the newcomer.
It is one of the smallest exoplanets, or planets outside the solar system, to be discovered in a habitable zone.
In astronomy, the habitable zone is the distance from a star at which a planet can maintain water on its surface, and consequently be capable of bearing life.