May 8, 2006

Multiple galaxy mergers continue in the Milky Way



The "Field of Streams" — this image is a map of stars in the outer regions of the Milky Way covering about one-quarter of the night sky, as observed by the Sloan Digital Sky Survey (SDSS-II). The trails and streams that cross the image are stars torn from disrupted Milky Way satellites. The color corresponds to distance, with red being the most distant and blue being the closest. The large, forked feature is the Sagittarius stream, further away from us (lower left) and closer to us (middle right). Other features marked are the Monoceros ring and the as yet unidentified stream.
(Credit: Vasily Belokurov, SDSS-II Collaboration)