Washington : Astronomers have discovered Earth’s ‘gassy twin’ with a mass similar to that of our planet in another solar system 200 light years away, reports PTI.
An international team discovered the first Earth-mass planet that transits, or crosses in front of, its host star. KOI-314c is the lightest planet to have both its mass and physical size measured. Surprisingly, although the planet weighs the same as Earth, it is 60 per cent larger in diameter, meaning that it must have a very thick, gaseous atmosphere.
“This planet might have the same mass as Earth, but it is certainly not Earth-like,” said David Kipping of the Harvard-Smithsonian Centre for Astrophysics (CfA). “It proves that there is no clear dividing line between rocky worlds like Earth and fluffier planets like water worlds or gas giants,” said Kipping, lead author of the discovery.
The team gleaned the planet’s characteristics using data from NASA’s Kepler spacecraft. KOI-314c orbits a dim, red dwarf star located approximately 200 light-years away. It circles its star every 23 days. The team estimates its temperature to be 104 degrees Celsius, too hot for life as we know it.
KOI-314c is only 30 per cent denser than water. This suggests that the planet is enveloped by a significant atmosphere of hydrogen and helium hundreds of miles thick.
It might have begun life as a mini-Neptune and lost some of its atmospheric gases over time, boiled off by the intense radiation of its star, researchers said.