WATCH: NASA Discovered a New Solar System, and 3 of Its Planets Are Potentially Habitable By Jared T. Miller They found a total of seven exoplanets in the Trappist-1 system, three of which are within the “habitable zone” where water may exist on their surfaces. Read More Tags: original video trappist-1 nasa exoplanets inhabitable More Feb. 22, 2017 Watch Now Would You Volunteer to be Infected With COVID-19? How Epidemics Made NYC Better The Story of a Coronavirus Infection WATCH: NASA Discovered 3 Potentially Habitable Planets