(NASA/Swift/Stefan Immler (GSFC) and Erin Grand (UMCP))
This mosaic of galaxy M31 in the Andromeda constellation merges 330 individual images taken by NASA's Swift satellite's Ultraviolet/Optical Telescope. The image shows a region 200,000 light-years wide and 100,000 light-years high.
This is the highest-resolution view of a neighboring spiral galaxy ever attained in the ultraviolet.
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