Artistic interpretation of Proxima Centauri b surface rotating in Proxima Centauri orbit.
Only 4.2 light years away is the closest star to our planet - Proxima Centauri. In its system, the planet Proxima Centauri b is present, the mass of which takes up only 1.3 Earth (although, depending on the viewing angle, it may turn out to be larger). This is an interesting object, as it is located in the zone of habitability of the star.
Proxima Centauri is an M-dwarf star with 1/10 mass of the Sun and a luminosity level of one thousandth of that of the Sun. Therefore, it seems dim, and its distance to the planet is 20 times shorter than the Earth-Sun distance. On the orbital path takes only 11.3 days.
Among the most common types of stars are M-dwarfs. Their small radii make it much easier to search for planets. Studies have confirmed that half of the M-dwarfs can contain exoplanets with 0.5-1.4 Earth radius, rotating in the habitable zone. Therefore, Proxima Centauri and its exoplanet worry scientists.
However, dwarf stars M are dangerous for their planets, as they reproduce strong ultraviolet and X-rays. They are able to completely destroy the atmosphere of the planet, especially if it is in the habitable zone. Therefore, now researchers are trying to find out whether Proxima Centauri b can even have an atmosphere in order to save life for at least a short time. Another danger is the magnetic activity of the star, which leads to corrosive radiation, and also reproduces stellar winds and coronal mass ejections. Up to this point, no one has made any special efforts to purposefully study active M-stars and their magnetic activity. Therefore, the astronomers Cecilia Garraffo, Jeremy Drake and Ofer Cohen launched a program to simulate the stellar winds and the magnetic field for active stars of M-dwarfs. This should explain the influence of forces on the atmospheres of the planets located in habitable zones.
Using Proxima Centauri as an example, they found that the stellar wind put pressure on exoplanets 10,000 times higher than in our case. Moreover, it was carried out unevenly. The exoplanet is destined to experience extreme pressure surges twice in orbit, which will cause its atmosphere to shrink and expand up to 3 times a day. In addition, it can experience supersonic wind conditions. All this adversely affects the atmosphere. But this question needs to be investigated in more detail.