U.S. researchers have discovered planets outside the Milky Way for the first time

Cambridge – Astronomers have now discovered nearly 5,000 planets in other stars – all of which are in our Milky Way. Now, for the first time, an international team of researchers is reporting a possible discovery of a planet the size of Saturn in a distant galaxy. Seen from Earth, the extraterrestrial planet left itself as it went ahead of the X-ray source and made it go out for a while like scientists. Journal of Natural Astronomy News.

“Planets in other galaxies cannot be detected by commonly used methods,” wrote Rosanne Di Stefano, of the Harvard & Smithsonian Center for Astrophysics in Cambridge, USA, and his colleagues. Because to do this, a star orbiting a planet is visible. With automatic telescopes, astronomers around the world search for planets that fluctuate slightly with their gravitational pull or occasionally pass in front of them, causing a measurable decrease in their brightness.

Di Stefano and his colleagues extended this concept to another type of celestial body: X-ray to binary stars. There, an ordinary star and a very compact object orbit each other – even a neutron star or black hole. Material flows from a normal star to a compact object – this produces X-rays. It can be detected at a greater distance than normal light from a star.

The new planet is 23 million light years away

In the archive data of the X-ray satellites Chandra and XMM-Newton, the researchers looked for abnormalities in the radiation of X-ray binary stars in three galaxies. M 51, they discovered what they were looking for in the galaxy M 51, 23 million light-years away: the radiation from the X-ray source M51-ULS-1 suddenly disappeared completely on September 20, 2012 during a measurement – about three hours. Then it suddenly appeared again. Di Stefano and his colleagues see only one plausible explanation for the sudden disappearance and reappearance of the X-ray source: a planet orbiting a binary star passed in front of the X-ray source when viewed from Earth.

From the eclipse of the X-ray source and the known data of the binary star, the researchers developed a model of a system that could recreate observations. Thus, Saturn orbits the binary star at a distance of ten to 100 times the distance between the Earth and the Sun. According to scientists, at this distance, it is also plausible that such a planet could sustain the formation of a neutron star or black hole from a large star.