Astronomers have discovered the oldest known (so far) exoplanet which might be capable of supporting life; the planet, Kapteyn b, is likely more than twice the age of the Earth. The planet was found by an international team of astronomers, led by Guillem Anglada-Escude from Queen Mary University.
Kapteyn b orbits a very old star, Kapteyn's Star, which is only 13 light-years from Earth in the constellation Pictor. It is classified as a "super-Earth" with a mass about five times that of the Earth, and orbits its star every 48 days.
Even with the small orbit close to the star, Kapteyn b is probably cooler than Earth, since Kapteyn's Star is a red dwarf, putting out less energy than our Sun. Given what is known about it so far however, it is considered possible that Kapteyn b could have liquid water on its surface, and so is considered to be potentially habitable.
With an estimated age of 11.5 billion years, there would have been ample time for life to develop on such a world if conditions were favorable. There are still a lot of unknowns at this point however about the actual conditions on the surface of the planet.
There is at least one other planet in this system, Kapteyn c, which is also a super-Earth but more massive than Kapteyn b and too cold for liquid water, with an orbit of 121 days.
The new findings were made using data from the HARPS spectrometer at the ESO's La Silla observatory in Chile.