Massive icy planet found in Earth’s backyard
WASHINGTON: A frozen and dimly lit planet may be orbiting the closest single star to our solar system, astronomers said last week, based on two decades of scientific observations.
The planet, estimated to be at least 3.2 times more massive than Earth, was spotted circling Barnard’s Star, a red dwarf only about six light years away from our solar system. It is believed to orbit Barnard’s Star every 233 days.
Planets orbiting stars beyond our solar system are called exoplanets. Nearly 4000 have been discovered and this one is the secondclosest to our solar system ever found. It is thought to be a ‘‘superEarth’’, one in a category of planets more massive than Earth but smaller than the large gas planets.
‘‘After a very careful analysis, we are 99% confident that the planet is there,’’ researcher Ignasi Ribas, of the Institute of Space Studies of Catalonia and the Institute of Space Sciences, said in a statement. ‘‘However, we’ll continue to observe this fastmoving star to exclude possible, but improbable, natural variations of the stellar brightness which could masquerade as a planet.’’
The only stars closer than Barnard’s Star are in the triplestar system Alpha Centauri, located a bit more than four light years from our solar system. Two years ago, astronomers announced the discovery of a roughly Earthsized planet there, circling Proxima Centauri in an orbit that might enable liquid water to exist on its surface.
The newly detected planet orbiting Barnard’s Star may not be so hospitable, with surface temperatures of perhaps minus 170degC. Its star gives it only 2% of the energy that the sun gives Earth.
The researchers studied the planet by combining measurements from several highprecision instruments mounted on telescopes around the world.
The research was published in the journal Nature. — Reuters