Author/s: I. Ribas, M. Tuomi, A. Reiners et al.
Reference: 2018 Nature 563 365 | Link
At a distance of 1.8 parsecs, Barnard’s star (Gl 699) is a red dwarf with the largest apparent motion of any known stellar object. It is the closest single star to the Sun, second closest after the alpha Centauri triple stellar system. Barnard’s star is also among the least magnetically active red dwarfs known and has an estimated age older than our Solar System. A combination of numerous measurements from high-precision radial velocity instruments reveals the presence of a low-amplitude but significant periodic signal at 233 days arising from a planetary companion. The candidate planet around Barnard’s star is a cold super-Earth with a minimum mass of 3.2 Earth masses orbiting near its snow-line. Because of its proximity to the Sun, the proposed planet has a maximum angular separation of 220 milli-arcseconds from Barnard’s star, making it an excellent target for complementary direct imaging and astrometric observations