NASA´s Gamma-ray Space Telescope Fermi discovered a structure in the Milky Way, which has never been seen before. It is about 50,000 light years large.
Astronomers guess that it might have been caused by an eruption of a supersized black hole in the middle of our galaxy millions of years ago.
Harvard-Smithsonian astronomer Doug Finkbeiner, who found the feature, said: "We don´t fully understand their nature or origin." A report on the structure will be published in The Astrophysical Journal.