German and British astronomers have compiled a list of nine planets whose potential inhabitants may know about the Earth and intelligent life on it, according to an article published in the journal MNRAS.
“The larger the planet, the more it blocks the light of the star around which it revolves. On the other hand, the "visibility" of a planet is more strongly influenced by how close it is to the star. Therefore, as paradoxical as it may sound, potential aliens will see the Earth and its neighbors more often than giant planets,”says Robert Wells of Queens University in Belfast (UK).
Back in the 1960s, the American astronomer Francis Drake developed a formula to calculate the potential number of alien civilizations based on the known properties of the Galaxy and the number of stars and planets in it. According to this formula, there should be a lot of extraterrestrial civilizations, but so far none have been found.
Wells says that scientists have long been trying to explain this discrepancy (the so-called Fermi paradox) by assessing the number of extraterrestrial civilizations and the reasons for their absence in our Galaxy from the Earth. Wells's team tried to solve this problem with a different approach - by comprehensively studying how well our planet and the traces of life on it would be visible to potential "brothers in mind" from other stellar systems.
Regions of the Galaxy where planets can be located, whose inhabitants can in principle see the Earth / 2MASS / A. Mellinger / R. Wells.
Calculations have shown that the probability of seeing the Earth or any other planet in the solar system from the outside is only 2.5%, and the chances of opening three at once can be called quite scanty - they do not exceed 0.027%.
Therefore, the inhabitants of only some exoplanets located in certain narrow strips of the sky will be able to see the Earth and study it. If, of course, they have instruments like the Kepler and Hubble telescopes. In total, there are only 65 such exoplanets, and the vast majority of them will be able to see only Mercury, and only nine of the Earth.
These include a small gas giant near the star HAT-P-11 in the constellation Cygnus, "hot Jupiter" WASP-68b in the constellation Capricorn, four large planets in the WASP-47 system in the constellation Aquarius, the emerging planet LkCa 15b in the constellation Auriga, large a gas giant near the star 1RXS 1609 in the constellation Scorpio and a planet near the white dwarf "cannibal" WD 1145 + 017 b in the constellation Virgo.
Promotional video:
But, according to scientists, these planets, in principle, cannot support life. This explains why astronomers have not yet managed to find a single habitable planet or extraterrestrial civilization.
Scientists hope that the new generation telescopes TESS and James Webb will help discover new planets in these zones, which will test this idea and understand if there is life outside the solar system.