Episodio 2: Lluvia sobre K2-18B

K2-18 is a Red Dwarf located 122 years light of the Earth, in the region of the sky that we identify with the constellation of Leo. In 2015 the Keppler Space Telescope, located in Earth’s orbit, detected through the transit technique, a planet Orbiting this star. The planet was called K2-18B. Two years later, in 2017, a second planet was detected to which It was named K2-18C. The latter, which orbited the star every nine days is a planet Neptune type, punished by radiation solar. However, K2-18B is very different. In 2017 scientists of the Institute for Research in Exoplanets, from the University from Montreal, led by the astrophysicist Bjrn Benneke, published the discovery that K2-18B was in the habitable zone of this star system, orbiting its star every 33 days For this analysis there were used data obtained by the Telescope Spitzer space.

01:45 - In this animation you can see the orbit of both planets. In red it is marked the 33-day orbit of K2-18B, transiting the goldilocks region of this system. The data obtained in 2017 classified k2-18B as a Super Earth, with a mass more than eight times that of our planet. What we know today about this world is even more intriguing. Because of its close orbit with the red dwarf, this super planet surely suffer tidal coupling, so that one from its sides will permanently look at the star.

The equilibrium temperature obtained 02:40 - It is -8 ° C plus / minus 5 degrees. Although it seems really low it’s just a little more lower than average or equilibrium temperature of planet Earth, which is a reason for intrigue For the scientists. Some scientists they maintain that because the planet suffers tidal anchor this final temperature would be the result of balancing a warm face and another in shadow. Other scientists, without However, they defend that an active atmosphere would allow the distribution of heat throughout the planet. The analysis of the data provided by Hubble, Spitzer space telescopes and Keppler allowed to deduce that K2-18B has an atmosphere based fundamentally on Helium and Hydrogen.

But in September of 2019 Nature Astronomy magazine published 03:40 - an article led by Angelos Tsiarias, of the Department of Physics and Astronomy from University College London. In this article the authors said that although the atmosphere of the Earth-type planets, for being cold and small, it was difficult to observe, the Superlands offered a unique opportunity to perform analysis spectroscopic of its atmospheres. In fact the spectrographic analysis of the atmosphere of K2-18B showed the presence of water molecules. Specifically had water vapor detected in the atmosphere of That alien planet. All the data seems point to that we find an atmosphere rich in hydrogen and helium with steam clouds of water.

And much more than that, temperatures 04:41 - detected were compatible with condensation of that water vapor, that is, it is possible Let there be rain on K2-18B. And although its host star is smaller and weak that our sun, like K2-18B orbits much closer to her, the truth is that solar radiation received on its surface It is very similar in terms of heat, to the that the Earth receives from the sun. K2-18B is the first extrasolar planet type Land detected within the habitability zone of his star and with evidences of atmosphere water container However and with everything this does not mean that the planet is habitable. This is because a dwarf orbits red at a small distance, just 0, 14 astronomical units. Remember for a moment that an astronomical unit is the average distance from the earth’s orbit to the sun.

Red dwarfs are stars of a high 05:48 - instability, capable of emitting supercalls that would degrade or destroy any nearby atmosphere, exposing possible bacteria to all series of cosmic evils. It is therefore necessary to analyze better and with better tools to this planet to be able to determine precisely if it is habitable or not. We can imagine that we landed in K2-18B. Its terrain is illuminated by the yellowish blurred light of a star that barely is seen among the dense clouds surrounding the planet. We can imagine mountains and hills, covered for snow and ice on its summits, and we can imagine streams and rivers, collecting water of rain or molten snow, driving it through ravines, far away, in that strange world. And if there are rivers and streams surely water accumulations will be generated in the plains Will there be beaches bordering lakes or seas in K2-18B? Today we do not know Almost everything from this mysterious planet.

07:27 - Fortunately, given the interest aroused in the scientific community, K2-18B has selected as one of the candidates for the observation of future telescopes James Webb and Ariel space telescopes that will come to revolutionize research exobiological in the coming years. The research and data analysis not is over. In fact the scientific articles discussing atmospheric characteristics of K2-18B are abundant at this time. And we have only begun to know the Mysteries of this distant world. .