Planetary scientists from the University of Montreal report the detection of water vapor, and perhaps even clouds of liquid water, in the atmosphere of planet K2-18b, 111 light years away.
"This represents the biggest step that has been taken to our ultimate goal of finding life on other planets., to prove that we are not alone. Thanks to our observations and our climate model of this planet, we have shown that its water vapor can condense into liquid water. This is the first time, "says the lead author of the finding, Björn Benneke, a professor at the Institute for Research on Exoplanets.
This exoplanet is approximately nine times more massive than our Earth and is in the habitable zone of the orbiting star. This M-type star is smaller and colder than our Sun, but due to the proximity of K2-18b to its star, the planet receives almost the same total amount of energy from its star that our Earth receives from the Sun.
The similarities between exoplanet K2-18b and Earth suggest to astronomers that the exoplanet may have a water cycle that may allow water to condense in clouds and rain of liquid water to fall. This detection was possible by combining eight traffic observations, the moment an exoplanet passes in front of its star, taken by the Hubble Space Telescope.
The University of Montreal is no stranger to the K2-18 system located 111 light years away. The existence of K2-18b was first confirmed by Professor Benneke and his team in a 2016 document using data from the Spitzer space telescope. The mass and radius of the planet were determined by former PhD student Ryan Cloutier of the University of Montreal and the University of Toronto.
Scientists now believe that the thick gas envelope of K2-18b probably prevents life as we know it on the planet's surface. However, the study shows that even these relatively low-mass planets, which are therefore more difficult to study, can be explored using astronomical instruments developed in recent years.
By studying these planets that are in the habitable zone of their star and have the right conditions for liquid water, astronomers are one step closer to directly detecting signs of life beyond our Solar System, reports the University of Montreal.
. (tagsToTranslate) larazon.es