Answer:
The star we today call TRAPPIST-1 was first discovered in 1999 by ... Telescope and ground-based telescopes discovered that the system ... Three of these planets are in the theoretical "habitable zone," the area around a star where rocky planets are most likely to hold liquid water. The TRAPPIST-1 system hosts seven Earth-sized, temperate exoplanets orbiting an ultra-cool dwarf star. As such, it represents a remarkable setting to study the formation and evolution of terrestrial planets that formed in the same protoplanetary disk
Explanation:
