For a planet that is favorable to the outward appearance of life, one of the most important requirements – between other geochemical, astrophysical and geophysical parameters – is that its orbit is in the habitable zone of one or another energy source, where the temperature Of liquid water. One of the most promising exoplanets is Next b, which revolves around Proxima Centauri, the closest star of the earth after the sun. And although at first it was speculated that the radiation was withered, a recent study suggested that can contain oceans and be suitable for life.
by means of mathematical models Similar to those used to analyze climate change on Earth, the researchers determined that Próxima b is capable of retaining large parts of liquid water on the surface, increase your chances of harboring living organisms enormously. The results of the study were published in Astrobiology.
Next Centauri. It is a small reddish star that belongs to the largest population of stars in the Milky Way: the red dwarfs. The distance to the sun is precisely determined by the parallax method: 4.24 light years.
Team estimates led by Antony of Genius, the NASA's Goddard Institute of Space Studies, pointed out that Proxima b is just enough to receive enough starlight and keep its surface above the freezing temperature of the water.
This exoplanet is 1.3 times larger than that of Earth and is located in Alpha Centauri, a triple star system at a distance of 4.2 light years. This set of 3 stars includes two bodies similar to the sun (Alpha Centauri A and B) and a red dwarf named Proxima Centauri.
To achieve these conclusions, they were modeled 18 virtual scenario & # 39; staking into account the effects of gigantic continents, extremely thin atmospheres, various atmospheric compositions and even changes in the salinity of the ocean. And in almost all models Próxima b ended with large open and sustainable seas on at least a part of the surface.
The mystery of life. For the work, the researchers determined that, hypothetically, Centauri B has an atmosphere and an ocean on the surface, which means that it is just enough distance to receive enough starlight
photo: NASA / JPL-Caltech / NASA / dpa find exoplanets system Trappist astronomy discovery of seven new planets planets system trapista
"The main message of our simulations," said Del Genio to Live Science Magazine, "is that there is more than a good chance that the planet is habitable."
At the end of 2016, a team from Queen Mary University in London, led by Guillem Anglada-Escudé, conducted a similar simulation and concluded that the ever-illuminated hemisphere of Proxima Centauri would be subjected to very high temperatures, while the dark hemisphere would be extremely cold.
What was not considered is that the habitable zone of Proxima Centauri is very close to the star. That means that the exoplanet has the tidal link. That is, the same side of Proxima Centauri b always is confronted with his star, as in the case of the moon, which always shows the same face to the earth.
In that sense, the new tests were more extensive since they he considered a dynamic and circulating ocean, which could transfer the heat from one side of the exoplanet to the other very effectively. In the researchers' findings, the movement of the atmosphere and the ocean combine so that "although the nocturnal side never sees starlight, there is an edge of liquid water that hangs around the equatorial region," Del Genio said. .
As an example, the researchers compared this circulation of heat with the maritime climates of our own planet. The east coast of the United States, without going any further, is warmer than it should be because the Gulf Stream carries hot water from the tropics. In California, on the other hand, ocean currents bring cold water from the north, so the west coast is colder than without that input.