(Credit: NASA/JPL-Caltech) TRAPPIST-1 opens up an exciting field for astronomers: a small, nearby, compact planetary system with seven Mars- to Earth-size worlds orbiting in days or weeks instead of months and years. What’s more, because their star is small and cool, all the planets may be habitable. Maybe. Two new papers are out on TRAPPIST-1. One makes the chances for life even more ripe, while the other virtually strips away all chances of habitability.
Let’s step back: until the last decade or so, most red dwarf or M-dwarf stars were thought to be active flaring stars, which would strip away planetary atmospheres under most accepted scenarios. But as more planets turned up in areas where planets would retain water aroudn M-dwarfs, scientists began to rethink their definition of habitability and come up with scenarios under which atmospheres and liquid water, including planets with strong magnetic fields, which is the reason ...
