TRAPPIST-1 is an ultra-cool red dwarf star with seven known planets. It lies in the constellation Aquarius approximately 40.66 light-years away from Earth, and it has a surface temperature of about 2,566 K (2,290 °C; 4,160 °F). Its radius is slightly larger than Jupiter's and it has a mass of about 9% of the Sun. It is estimated to be 7.6...