杏吧原创

A STELLAR neighbour that we have stared at for years appears to have a planet after all.

Barnard鈥檚 star is a red dwarf just 6 light years away. That makes it the next closest star to the sun after those in the Alpha Centauri system, and an obvious target for planet-spotters. But despite many astronomers looking, no planets ever showed up.

Ignasi Ribas at the Institute of Space Studies of Catalonia in Spain and his colleagues may have hit the jackpot. They combined the results of earlier surveys, looking for the wobble of the star caused by the tug of an orbiting object. So small was the effect of their proposed planet, GJ 699 b, on Barnard鈥檚 star that they needed 771 readings taken over 20 years to be sure they had seen something (Nature, ).

GJ 699 b is thought to have three to four times Earth鈥檚 mass and a surface temperature of -150掳C.

This article appeared in print under the headline 鈥淣earby alien world hiding in plain sight鈥�