Barnards Stern hat einen bestätigten Planeten

> The planet, dubbed “Barnard b,” orbits its star at only 0.02 astronomical unit, 20 times closer than Mercury orbits the Sun. This distance puts it well inside [closer than] the star’s habitable zone: With a surface temperature of an estimated 400K (260°F), there is certainly no liquid water on its surface, even though the star itself is 2,500 K cooler than our Sun.

and

> González’s teams used the radial velocity method, measuring the tiny wobble of Barnard’s star caused by the gravitational tug of its planetary companion. Gonzalez’s team, though, had a much sharper tool at their disposal: the fiber-fed, high-resolution Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO) at the European Southern Observatory’s Very Large Telescope in Chile.

> “With ESPRESSO, we are aiming at a [radial velocity] precision of about 10 cm/s, similar to the effect of the gravitational pull of Earth on the Sun,” explains González. Older spectrographs are much less precise, which makes it difficult for them to detect low-mass exoplanets.