Thermal Structure and Major Ion Composition of the Venus Ionosphere: First RPA Results from Venus Orbiter

  title={Thermal Structure and Major Ion Composition of the Venus Ionosphere: First RPA Results from Venus Orbiter},
  author={William C. Knudsen and Karl Spenner and Robert C. Whitten and John R. Spreiter and Kent L. Miller and V. Novak},
  pages={757 - 763}
Thermal plasma quantities measured by, the retarding potential analyzer (RPA) are, together with companion Pioneer Venus measurements, the first in situ measurements of the Venus ionosphere. High ionospheric ion and electron temperatures imply significant solar wind heating of the ionosphere. Comparison of the measured altitude profiles of the dominant ions with an initial modlel indicates that the ionosphere is close to diffusive equilibrium. The ionopause height was observed to vary from 400… 

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EUV Fluxes in the solar spectrum below 2000 Å

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