Venus Ionosphere: Photochemical and Thermal Diffusion Control of Ion Composition

@article{Bauer1979VenusIP,
  title={Venus Ionosphere: Photochemical and Thermal Diffusion Control of Ion Composition},
  author={Siegfried J. Bauer and Thomas M. Donahue and Richard E. Hartle and Harry A. Jr. Taylor},
  journal={Science},
  year={1979},
  volume={205},
  pages={109 - 112}
}
The major photochemical sources and sinks for ten of the ions measured by the ion mass spectrometer on the Pioneer Venus bus and orbiter spacecraft that are consistent with the neutral gas composition measured on the same spacecraft have been identified. The neutral gas temperature (Tn) as a function of solar zenith angle (χ) derived from measured ion distributions in photochemical equilibrium is given by Tn (K) = 323 cos1/5χ. Above 200 kilometers, the altitude behavior of ions is generally… 

Dynamical response of the dayside ionosphere of Venus to the solar wind

Dayside ion composition measurements made by the orbiter ion mass spectrometer and the orbiter electron temperature probe on the Pioneer Venus orbiter are used to infer the dominant processes

Ion temperature anisotropy and heat flow in the Venus lower ionosphere

Motivated by the recent observations of supersonic ion flow in the Venus ionosphere near the terminator, we have studied the extent to which such a flow can induce an ion temperature anisotropy and a

Model calculations of the dayside ionosphere of Venus - Ionic composition

Comprehensive model calculations of the dayside ion density distributions were carried out and compared with results from the Pioneer Venus ion mass spectrometer. The coupled continuity and momentum

Comparison of Calculated and Measured Ion Densities on the Dayside of Venus

The distributions of five minor ions are calculated for the chemically controlled region and the agreements are poor, an indication that the present understanding of the Venus minor ion chemistry is still incomplete.

A Two-Dimensional Model of the Ionosphere of Venus

A substantial nightside ionosphere has been observed on Venus during most orbits of the Pioneer Venus Orbiter. However, on some orbits during which the solar wind dynamic pressure was large, the

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At Venus H + is expected to be under diffusive equilibrium above about 400 km, but it is difficult to verify this under normal circumstances, because solar wind interaction terminates the subsolar

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Simplified multicomponent diffusion calculations are made for the ionosphere of Venus. Large differences in temperature between electrons and ions and appreciable temperature gradients that are near

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