The first planet outside our galaxy was observed. It would be about the size of Saturn and is located in the galaxy Messier 51, 28 million light-years away from Earth.
Behind this interesting discovery is an international group led by the Harvard-Smithsonian Center for Astrophysics in Cambridge, USA, which published the results in Nature Astronomy. The discovery was made using an innovative method that studies X-rays observed by NASA’s Chandra Space Telescope.
Astronomers have found clues as to what may be the first planet ever discovered outside our galaxy. Nearly 5,000 “exoplanets” – worlds orbiting stars beyond our Sun – have been found so far, but all of these have been located within the Milky Way galaxy.
“The method we have developed and employed is the only currently implementable method for discovering planetary systems in other galaxies,” Dr. Di Stefano, of the Harvard-Smithsonian Center for Astrophysics in Cambridge, in the United States. “It is a unique method, particularly suitable for finding planets around X-ray tracks at any distance from which we can measure a light curve.”