Astronomers discover three planets in 'habitable zone'Tuesday 25 June 2013 23.02
Astronomers have discovered a new cluster of stars relatively close to earth which contain three 'Super-Earth' sized planets which could, in theory, be suitable for sustaining life.
It is the first time that a system has been found with what is being described as "a fully packed habitable zone".
The star, named Gliese 667C, is already a very well-studied star which is just over one third of the mass of the Sun.
It is part of a triple star system known as Gliese 667, which is situated 22 light-years away in the constellation of Scorpius.
This is considered by astronomers to be quite close to us, within the context of the area around the Sun.
It was known from previous studies of Gliese 667C that it hosts three planets, one of which is within what is known as the habitable zone - the area around a star within which planets with sufficient atmospheric pressure and correct temperature can sustain water on their surface.
However, a re-examination of the system by a team of astronomers using data from the European Southern Observatory's Very Large Telescope, and the facilities of two other observatories, has found evidence of up to seven planets around the star.
The team has confirmed that three of these planets are super-Earths - planets bigger than Earth, but smaller than planets like Uranus or Neptune.
The planets are within their star's habitable zone - the first time that three such planets have been spotted orbiting in this zone in the same system.