The latest hunt for alien signals in the TRAPPIST-1 planetary system has test-driven a new strategy that will allow astronomers to perform a more efficient, targeted search for technological extraterrestrial life in the future.
TRAPPIST-1 is a multi-planet system about 40.7 light-years away. Its seven rocky worlds, some of which lie in the habitable zone — the zone around a star where it isn't too hot nor too cold for a planet to host liquid water — are all bunched up so tightly that they transit their star every few days. The number of planets and their relative proximity to us make the TRAPPIST-1 system a tantalizing target for the search for extraterrestrial intelligence (SETI).
