Astronomers find frozen supertierra near our Solar System
An international team found a frozen Super Earth that orbits the second closest star system or star closest to our Sun, according to a study published Wednesday in the journal Nature.
The cold planet revolves around the star Bernard, our fourth closest neighboring star in general, after the Alpha Centauri three-star system. Star Bernard, only six light years from Earth, smaller and older than our Sun and is one of the most active red dwarfs known.
Astronomers sew data from seven instruments, including the Discover Planet spectrograph on the Magellan II telescope at the Carnegie Institution for Science in Washington DC.
"After very careful analysis, we have more than 99% confidence that the planet is there," said the lead author of the article, Ignasi Ribas, from the Institute of Spatial Studies of Catalonia in Spain.
Called the Barnard b star, this planet has at least 3.2 times the mass of the Earth and orbits its star every 233 days at a distance where water will freeze. Scientists estimate the surface temperature to be minus 150 degrees Celsius.
Using a radial velocity technique, astronomers detect small movements caused by the Earth's gravity in the star's orbit.
They said the characteristics of the newly discovered planet made it an excellent target for direct imaging using next-generation instruments such as the Wide Field Infrared Inspection Telescope (WFIRST) from NASA.