Ultraviolet Imaging Spectroscopy Shows an Active Saturnian System

  title={Ultraviolet Imaging Spectroscopy Shows an Active Saturnian System},
  author={Larry W. Esposito and Joshua E. Colwell and Kristopher Larsen and William E. McClintock and A. Ian F. Stewart and Janet Tew Hallett and Donald E. Shemansky and Joseph M. Ajello and Candice J. Hansen and Amanda R. Hendrix and Robert A. West and H. Uwe Keller and Axel Korth and Wayne R. Pryor and Ralf Reulke and Yuk L. Yung},
  pages={1251 - 1255}
Neutral oxygen in the saturnian system shows variability, and the total number of oxygen atoms peaks at 4 × 1034. Saturn's aurora brightens in response to solar-wind forcing, and the auroral spectrum resembles Jupiter's. Phoebe's surface shows variable water-ice content, and the data indicate it originated in the outer solar system. Saturn's rings also show variable water abundance, with the purest ice in the outermost A ring. This radial variation is consistent with initially pure water ice… 

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