In 2019, two studies combining data from the Hubble, Kepler and Spitzer space telescopes detected a significant amount of water vapor in the atmosphere of K2-18b, an exoplanet about 120 light years away, between two and three times larger than Earth but 8.6 times more massive. The discovery suggested the presence of a vast ocean of water on its surface and the possibility that K2-18b was a 'hicean' planet (a name obtained by joining 'hydrogen' and 'ocean'), a hypothetical type of habitable world. , recently proposed and characterized by being hot, oceanic and with a hydrogen-rich atmosphere. That extreme, however, could not be confirmed, since… See more
