Venus Upper Atmosphere Neutral Gas Composition: First Observations of the Diurnal Variations

  title={Venus Upper Atmosphere Neutral Gas Composition: First Observations of the Diurnal Variations},
  author={Hasso Bernhard Otto Niemann and Richard E. Hartle and Alan E. Hedin and Wayne T. Kasprzak and Nelson W. Spencer and Donald M. Hunten and George R. Carignan},
  pages={54 - 56}
Measurements of the composition, temperature, and diurnal variations of the major neutral constituents in the thermosphere of Venus are being made with a quadrupole mass spectrometer on the Pioneer Venus orbiter. Concentrations of carbon dioxide, carbon monoxide, molecular nitrogen, atomic oxygen, and helium are presented, in addition to an empirical model of the data. The concentrations of the heavy gases, carbon dioxide, carbon monoxide, and molecular nitrogen, rapidly decrease from the… 
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Measurements of O, He, and Ar from neutral gas mass spectrometers on four satellites (Ogo 6, San Marco 3, Aeros A, and AE-C) and inferred O2 and H densities from an ion mass spectrometer on AE-C have
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