Astronomers using the Hubble Space Telescope (HST) have found evidence for a shell made up of stars that is embedded in the halo of our Milky Way Galaxy.
By analyzing the motion of a small sample of stars the astronomers detected a higher sideways motion that would be expected. One possible explanation is that billions of years ago our galaxy shredded a small satellite galaxy that caused its stars to be absorbed yet they maintained some of their original orbital characteristics. These stars were then found to form a shell in the outer reaches of the galaxy.
Read More About This: http://hubblesite.org/newscenter/archive/releases/2013/07/full/
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