A series of papers out today gives us further insights into the TRAPPIST-1 system discovered in 2016.

The seven planets that make up the system orbit a dim red dwarf star much smaller and cooler than our own Sun. The planets’ orbits are much tighter than in our solar system, and they’re all closer to their home star than Mercury is to the Sun. Three of them are thought to be in the “habitable zone” where liquid water could exist.
The TRAPPIST Seven
The system is relatively close, only 4