Contact: Francis Reddy
NASA/Goddard Space Flight Center
Caption: This composite of C/2013 A1 (Siding Spring) merges Swift UVOT images taken between May 27 and 29, 2014. Sunlight reflected from the comet's dust, which produces most of the light in this image, appears yellow; violet shows ultraviolet light produced by hydroxyl (OH), a molecular fragment of water.
Credit: NASA/Swift/D. Bodewits (UMD), DSS
Usage Restrictions: None
Related news release: NASA's swift satellite tallies water production of Mars-bound comet