Closest known exoplanet is ‘just’ 4.24 light-years away orbiting Proxima Centauri
L. Calçada, Nick Risinger (skysurvey.org)/ESO
Worlds in the Alpha Centauri system — the trio of stars closest to our sun — have been a staple of science fiction for decades. From Star Trek to Avatar, writers have dreamed up exotic landscapes (and inhabitants) for interstellar explorers to encounter. Now a planet around one of those stars is no longer fiction.
In August, breathless headlines heralded the discovery of a small, potentially habitable planet orbiting Proxima Centauri, a dim red dwarf star just 4.24 light-years away (SN: 9/17/16, p. 6). The planet, Proxima b, isn’t the first roughly Earth-mass planet discovered. It’s not the first seen in a star