GJ 667C: First System with Multiple Super-Earths in the Habitable Zone

The M1.5V star GJ 667C (Gliese 667C) is a faraway member of a triple star system. It orbits the central binary GJ 667AB (a K3V+K5V binary system) at a projection distance of ~230 AU. GJ 667C is known to host several super-Earth planets. The first planet discovered around this star was a hot super-Earth in a 7.2-day orbit (Bonfils 2009). However, it was the subsequent discovery and confirmation of a 4.5 Earth mass planet, GJ 667Cc, in the habitable zone of this star (Anglada-Escudé et al. 2012; Delfosse et al. 2013) that made this system one of the most significant planetary systems known to date. The planet GJ 667Cc is the first confirmed potentially habitable planet. Figure 1 shows an artist’s rendering of this system.

Fig. 1

Artist’s rendering of the triple star system GJ 667 and planets GJ 667Cb and GJ 667Cc