Galileo ultraviolet spectrometer observations of atomic hydrogen in the atmosphere of Ganymede

@article{Barth1997GalileoUS,
  title={Galileo ultraviolet spectrometer observations of atomic hydrogen in the atmosphere of Ganymede},
  author={C. Barth and C. Hord and A. Stewart and W. Pryor and K. Simmons and W. McClintock and J. Ajello and K. Naviaux and J. Aiello},
  journal={Geophysical Research Letters},
  year={1997},
  volume={24},
  pages={2147-2150}
}
Atomic hydrogen Lyman alpha radiation (121.6 nm) has been measured in emission from the atmosphere of Ganymede with the Galileo ultraviolet spectrometer. An exospheric model with the following parameters has been fit to the observational data: atomic hydrogen density directly above the surface (radius 2634 km) equal to 1.5 × 104 atoms cm−3 scale height 2634 km, exospheric temperature 450 K. A model calculation of the photodissociation of water vapor from surface ice at 146 K is used to obtain… Expand

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