An exoplanet of terrestrial size was discovered and at the same distance from the star as we are from the Sun. But her star is too dim, and the whole planet, apparently, is covered with a snow-icy desert.
In this work, American astronomers used not the most common method of gravitational microlensing. If the radiation of a distant star, moving towards us, passes by another star, its gravity distorts the trajectory of light, acting as a magnifying lens. If the second star has a planet, it is sometimes possible to find its contribution to lensing, which changes with the same frequency with which the planet moves in its orbit.
This approach allowed scientists to find OGLE-2016-BLG-1195Lb, the smallest ever discovered by microlensing. For the first time, the data of the OGLE experiment indicated an unusual object, after which the authors used three telescopes of the Korean KMTNet project, as well as the Spitzer space observatory, for observations. This made it possible to collect enough data not only to detect the planet, but also to estimate its orbit and mass.
In an article published by the Astrophysical Journal Letters, OGLE-2016-BLG-1195Lb is described as a planet with a mass of about 1.43 Earth masses, located almost exactly the same distance from the star as Earth from the Sun. However, with the star itself, things are far from rosy: its mass is estimated at only 7.8 percent of the solar mass, so scientists are not completely sure whether it should be considered a star.
The object is located in 13 thousand light years, and the authors attributed it to the class of ultracold dwarfs. The temperature on its surface is too low, which means that, despite all the similarities with the Earth, there can be no life in our usual sense at OGLE-2016-BLG-1195Lb. If it was formed in about the same way as our planet, then there should be enough water on it, but all of it is in the form of eternal ice that covers the distant planet-"snowball".
Sergey Vasiliev
