TRAPPIST-1’s seventh planet is a chilly world

TRAPPIST 1 system

FAR OUT TRAPPIST-1h (outermost magenta line) orbits its star in about 19 days, new observations show. The orbits of the system’s other six planets are shown in red, orange, yellow, green, blue and purple.

NASA

When astronomers in February announced the discovery of seven planets orbiting a supercool star, details about the outermost planet were sketchy.