The enceladus and oh tori at saturn

  title={The enceladus and oh tori at saturn},
  author={Robert E. Johnson and H. Todd Smith and Orenthal J. Tucker and M. Liu and Martin Burger and Edward C. Sittler and Robert L. Tokar},
  journal={The Astrophysical Journal},
The remarkable observation that Enceladus, a small icy satellite of Saturn, is actively venting has led to the suggestion that ejected water molecules are the source of the toroidal atmosphere observed at Saturn for over a decade using the Hubble Space Telescope (HST). Here we show that the venting leads directly to a new feature, a narrow Enceladus neutral torus. The larger torus, observed using HST, is populated by charge exchange, the process that limits the lifetime of the neutrals in the… 

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