Adapted from chapter 10 of Dispatches from Planet 3: 32 (Brief) Tales on the Solar System, the Milky Way, and Beyond, by Marcia Bartusiak, a faculty member in MIT’s School of Arts, Humanities, and Social Sciences (Yale University Press, 2018).
IN 2017 AN INTERNATIONAL TEAM OF ASTRONOMERS THRILLINGLY REVEALED, after examining a collection of data gathered by both NASA’s Spitzer Space Telescope and an array of telescopes around the world, that they had found an extrasolar planetary system with at least seven members—all roughly the size of the Earth. These newfound celestial bodies were closely circling a red, Jupiter­-sized star known as TRAPPIST­-1. The star had been named after the TRAnsiting Planets and PlanetesImals Small Telescope network in Chile and Morocco, which first encountered this extrasolar system. At least three of TRAPPIST­-1’s rocky planets are likely to harbor liquid water, but so could all seven.