17 Sep 2011

Planet with two suns found

5:34 am on 17 September 2011

A planet orbiting two suns has been found by the Kepler telescope which is searching the Milky Way for planets that resemble Earth.

The planet has been named Kepler-16b. It lies some 200 light years from Earth and is thought to be an uninhabitable cold gas giant, like Saturn.

Though there have been hints in the past that planets circling double stars might exist - "circumbinary planets", as they are known - scientists say this is the first confirmation.

They say it means there is a double sunset when the day ends on Kepler-16b.

The BBC reports Kepler-16b's two suns are smaller than ours - at 69% and 20% of the mass of our Sun - making the surface temperature an estimated -100 to -150F (-73 to -101C).

The planet orbits its two suns every 229 days at a distance of 65m miles (104m km) - about the same distance out as Venus.

The Kepler telescope was launched in 2009 by NASA. It is designed to scour our section of the Milky Way for Earth-like planets.

Kepler finds stars whose light is regularly dimmed when an orbiting planet passes between the star and the telescope.