Astronomers of the Smithsonian Astrophysical Observatory (USA) may have discovered the first exoplanet outside the Milky Way Galaxy. Signs of its existence were recorded by the X-ray Space Telescope Chandra. This is reported in the article published in the Nature Astronomy magazine.
The candidate for exoplanet is located in the galaxy whirlpool or M51, which is at a distance of about 30 million light years. Until now, astronomers have found exoplants and candidates for exoplanets in the Milky Way Galaxy, and almost all of them are at a distance of less than three thousand light years from the Earth. Scientists have discovered a space object due to a transit event when the brightness of any star falls due to the body passing on its background. In this case, the observation was conducted in the X-ray spectrum.
The candidate for the exoplanet blocked the radiation from the double X-ray source of M51-ULS-1, which consists of a neutron star or a black hole that attracts gas from a closely located companion star 20 times the massive sun. The substance forms an accretion disc, where heats up and begins to emit X-ray radiation. This area is small and can completely sunow the planet, which blocks all or almost all the X-ray light. It is estimated that the planet should be among the Saturn and rotate around the compact object at a distance of two times greater than Saturn from the sun.
The sizes of the orbit of the candidate planet mean that the space object will no longer pass in front of its double partner for about 70 years, which prevents any attempts to confirm observation for decades. However, due to the uncertainty of the period of rotation, scientists do not know exactly when the second transit occurs.