New Planet Is Earth’s Twin 200 Light Years Away
The planet is also much hotter than Earth, with scientists estimating its surface temperatures to be around 104C – unsupportive of most life forms on Earth.
KOI-314c is suspected to have a thick gaseous atmosphere, making the planet only 30% denser than water.
However, despite a similar weight, astronomers said the planet is not considered “Earth-like”.
“This planet might have the same mass as Earth, but it is certainly not Earth-like,” said lead astronomer Dr David Kipping, from the Harvard-Smithsonian Centre for Astrophysics in the US.
He added: “It proves that there is no clear dividing line between rocky worlds like Earth and fluffier planets like water worlds or gas giants.”
Scientists made the discovery by accident while searching for moons using the powerful Kepler space telescope.
“When we noticed this planet showed transit timing variations, the signature was clearly due to the other planet in the system and not a moon,” said Dr Kipping.
“At first we were disappointed it wasn’t a moon, but then we soon realised it was an extraordinary measurement.”
Evidence of the new planet was presented at the annual meeting of the American Astronomical Society in Washington DC.