In 3000 light-years from us, an exoplanet of the terrestrial type was discovered near a solar-type star and in practically the same orbit.
Of the more than 4,000 known exoplanets today, most are gas giants like Jupiter or Neptune. "Super-earth" - terrestrial planets with a mass of no more than 10 times ours - only a few dozen have been discovered. Even fewer of them are at such a distance from their star that they maintain a moderate temperature on their surface, allowing them to retain liquid water and provide conditions for the development of life. And all known potentially habitable planets are in orbit near red dwarfs.
Such stars are the most common in the galaxy, but whether they are suitable for life remains unclear. On the one hand, red dwarfs remain stable many times longer than stars like ours, giving evolution a huge amount of time. On the other hand, their radiation is weaker and mostly falls on the low-energy infrared range.
In order to get enough heat, the planet will have to move in a very close orbit, where it will experience powerful tidal forces due to the dwarf's gravity. The resulting deformations of the planet can trigger permanent and hyperactive volcanism. In addition, from time to time, red dwarfs emit extremely powerful flares: calculations show that they are capable of completely sterilizing the surface of nearby planets.
However, recently astronomers from the German Institute for Solar System Research of the Max Planck Society managed to discover the first potentially habitable planet located in a solar-type star system. At a distance of just over 3100 light-years, the yellow dwarf Kepler-160 has a mass of 0.9 times the mass of the Sun, a radius of 1.1 times its radius, and a luminosity almost the same as that of the Sun.
Until now, it has known two exoplanets, both significantly larger than the Earth and in orbits too close to the star: apparently, these are incinerated, incandescent worlds. However, in a new article published in the journal Astronomy & Astrophysics, René Heller and his colleagues report two more candidates, whose presence is indicated by deviations in the motion of known planets.
One of them, the giant Kepler-160d, does not pass against the background of its star's disk, therefore it was not noticed in the data of previous observations. But another one turned out to be much more interesting - KOI-456.04, the radius of which is estimated to be only 1.9 times the radius of the Earth, and it makes a complete revolution in orbit in 378 days. Thus, KOI-456.04 is surprisingly close to our familiar world both in itself and in the characteristics of its star. According to astronomers, until now, no such distant system has been known.
It should be added that the calculations that found KOI-456.04 in the archived data are not yet reliable enough - and she remains in candidate status until new observations. The authors of the work hope that the European mission PLATO, a new space telescope for searching for exoplanets, which is preparing to launch in 2026 and is aimed at detecting precisely "super-earths", will help to do this.