Planet in orbit around the star of Barnard (upper left corner). Hubble Art Print
Astronomers have discovered a super-Earth orbiting around the star of Barnard, a red dwarf located about six light-years from the sun.
This Super-Earth has mass at least 3.2 times that of Earth, and completes a revolution around the star of Barnard in 233 days. It is potentially a rocky planet and was named the star of Barnard B.
Located six light years away from the Sun, Barnard's star is the second star system closest to the Sun, after the triple Alpha Centauri system; is also the single star closest to the sun. It is an extremely weak red dwarf, being only 3% brighter than the sun. It is named after E Barnard, an American astronomer who measured its movement for the first time in 1916.
Astronomers have discovered Barnard's star B using the radial velocity method. This technique allowed them to detect oscillations in Barnard's star, resulting from the gravitational pull of the orbiting planet. The team also re-examined the data collected by different telescopes over the last 20 years.
New observations of modern instruments – including the ESO / HARPS instrument in Chile, the CARMENES spectrometer in Spain and the HARPS-N instrument in the Canary Islands – were also examined in detail.
"After a very careful analysis, we are more than 99% confident that the planet is there, as this is the model that best fits our observations," said Ignasi Ribas of the Institut d'Estudis Espacials de Catalunya and the Space Institute. Sciences in Spain.
"However, we must remain cautious and collect more data to resolve the case in the future."
According to astronomers, the star of Barnard b orbits near the snow line of its host star, which means that it is beyond the habitable zone. It is probably a frozen world, with a surface temperature of about -170 degrees Celsius. It is probably a rocky planet, rich in volatiles, with most being frozen on the surface.
The Barnard B star is now the second closest known exoplanet to our Sun, after Proxima B surrounding Proxima Centauri, a red dwarf. Astronomers also believe that this exoplanet possibly has a massive atmosphere, which could potentially make conditions more hospitable to life.
The research team – including astronomers from Queen Mary University in London, the European Southern Observatory, the Institut d'Estudis Espacials de Catalunya and the Institute of Space Sciences / CSIC in Spain – published his article in the journal Nature.