European astronomers have reported that they have discovered a new extrasolar planet that is several times more massive than Earth. This is a super-earth turning around a nearby star GJ 625.
Super-Earths are planets that surpass the Earth in massiveness, but do not reach the parameters of Neptune. Usually this term is applied to the planetary mass, but sometimes they are called planets with a radius of 2-4 Earth.
The star is 21 light years away from us and is a M-type dwarf, which reaches three solar masses. These are important objects, since they provide a large percentage of the probability of the presence of alien worlds. But finding a planet near a star with a small mass is difficult, because the signals of stars from rotation can simulate planetary ones.
Phases of the planetary signal curve detected in GJ 625 with the parameters of the MCMC model. On the left - CCF measurements, and on the right - TERRA. Gray dots are the detected signals with induced activity, and the red dots are the same as the phase with 0.1. Research GJ 625 began in 2013 by a group of astronomers led by Alejandro Mascareño from the Institute of Astrophysics of the Canary Islands. For observations, a high-speed radial accelerator of planetary velocity was used for the northern hemisphere spectrograph (HARPS-N).
Scientists tracked 151 radial velocities of the time series as part of a search for red dwarf exoplanets.
The new world is designated as GJ 625 b. It is 2.8 times the Earth’s mass, making it the easiest world found near the M2 star. On the orbital period takes 14.6 days, and the distance from the star - 0.08 a. This is very close, because Mercury is distant from the Sun by 0.38 a. e.
Studies of radial velocity helped us to understand that we have a super-earth, located on the inner edge of the habitable zone. The surface temperature reaches 350 K. Scientists think that there may be water in a liquid state. To determine this, you need to explore the atmosphere.