Atomic Hydrogen on Mars: Measurements at Solar Minimum

  title={Atomic Hydrogen on Mars: Measurements at Solar Minimum},
  author={Joel S. Levine and David S. Mcdougal and D. E. Anderson and Edwin S. Barker},
  pages={1048 - 1051}
The Copernicus Orbiting Astronomical Observatory was used to obtain measurements of Mars Lyman-α (1215.671-angstrom) emission at the solar minimum, which has resulted in the first information on atomic hydrogen concentrations in the upper atmosphere of Mars at the solar minimum. The Copernicus measurements, coupled with the Viking in situ measurements of the temperature (170� � 30�K) of the upper atmosphere of Mars, indicate that the atomic hydrogen number density at the exobase of Mars (250… 
Three‐dimensional structure in the Mars H corona revealed by IUVS on MAVEN
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Measurements and models of the luminosity that originates in the Martian and Venusian atmospheres, including dayglow, nightglow and aurora, are compared. Most of the emission features considered
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Mariner 9 Ultraviolet Spectrometer Experiment: Initial Results
The ultraviolet airglow spectrum of Mars has been measured from an orbiting spacecraft during a 30-day period in November-December 1971 by measuring the spectral characteristics of particle scattering and the emission rates of the carbon monoxide Cameron and fourth positive bands.
Mars: An Evolving Atmosphere
  • M. McElroy
  • Physics, Environmental Science
  • 1972
The relative outgassing rates of H2O and CO2 on Mars are comparable with terrestrial values, although absolute rates for Mars are lower by a factor of 103.
OGO-5 measurements of the Lyman-alpha sky background in 1970 and 1971
The results of measurements of the Lyman-alpha sky background emission at 1216 A, made by two different UV photometers during the last three 'spin-up' maneuvers (enabling more than 50% of the sky to
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The upper atmosphere of Mars is surprisingly cold with average temperatures for both Viking 1 and Viking 2 of less than 200�K, and there is significant vertical structure.
The Escape of Light Gases from Planetary Atmospheres
Abstract The Jeans-Spitzer treatment of atmospheric escape by evaporation must be supplemented, for a mixture of gases, by a discussion of the mutual diffusion and mixing of the components. A recent
Mariner 6: Ultraviolet Spectrum of Mars Upper Atmosphere
Emission features from ionized carbon dioxide and carbon monoxide were measured and the Lyman alpha 1216-angstrom line of atomic hydrogen and the 1304-, 1356-, and 2972-angston lines of atomic oxygen were observed.