Planet: GJ 625 b

Discovered by: A. Suárez Mascareño et al. using HARPS-N spectrograph on the Telescopio Nazionale Galileo

Date: September 28, 2017

Key Facts: This discovery is a super Earth only 21 light-years away in the inner habitable zone of its small, red 'M dwarf' star. Almost 3 times more massive than Earth, this exoplanet is 21 light-years away. It takes only two weeks to orbit its star, closer than Mercury is to the Sun. But since M dwarf stars are cool compared to our Sun, the planet still has the potential for water.

What's new: A super Earth isn't super because it's twice as cool as Earth– it's super because it's twice as massive. Besides the mass of this planet, we don't know anything about the surface or atmosphere, aka whether it would be friendly to life. But super-Earth-size planets around M dwarf stars are increasingly popular targets in the search for life. They are the most common planet type in the galaxy. So next time you imagine life out there, try picturing it on a world with a red star.

See details and check the official NASA planet count at the NASA Exoplanet Archive

Paper: "A super-Earth on the inner edge of the habitable zone of the nearby M-dwarf GJ 625"