Posted: Wed, Nov 10, 2010, 7:19 AM ET (1219 GMT)
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Astronomers using data from a NASA spacecraft have discovered giant gamma-ray-emitting structures extending from the center of the Milky Way galaxy. Analysis of observations by NASA's Fermi Gamma-ray Space Telescope revealed "bubbles" extending above and below the galactic center, out to distances of 25,000 light-years. The structures had not been seen previously because they were lost in a "fog" of other gamma-ray emissions that astronomers were able to account for in the new study. The source of the gamma-ray bubbles is uncertain, but astronomers speculated it could be linked to particle jets emitting from the supermassive black hole in the galaxy's core, or as a result of an episode of star formation.