The Atmosphere of Callisto

  title={The Atmosphere of Callisto},
  author={Yuk L. Yung and Mao‐Chang Liang and Brendan Lane and Robert T. Pappalardo and Mark B. Allen},
During the Galileo flybys of Callisto in 1999, a CO_2 atmosphere and an ionosphere were detected. Using the Caltech/Jet Propulsion Laboratory one-dimensional KINETICS model, we have successfully simulated the observed electron density within a factor of 2, while satisfying the observational constraints on carbon and oxygen atoms. We conclude that photoionization of CO_2 alone is insufficient to produce the observed electron density. An atmosphere 20–100 times denser than the CO_2 atmosphere… 

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