K
K. Spenner
Researcher at Fraunhofer Society
Publications - 19
Citations - 1014
K. Spenner is an academic researcher from Fraunhofer Society. The author has contributed to research in topics: Venus & Atmosphere of Venus. The author has an hindex of 14, co-authored 19 publications receiving 995 citations.
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Transport of ionospheric O+ ions across the Venus terminator and implications
TL;DR: The Pioneer Venus orbiter retarding potential analyzer demonstrated that the velocity of ionospheric O(+) ions in the vicinity of the terminator is directed antisunward and radially inward toward the planet in the range of 1-8 km/s as mentioned in this paper.
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Solar zenith angle dependence of ionospheric ion and electron temperatures and density on Venus
TL;DR: The measurements taken during the first year of the Pioneer Venus orbiter retarding potential analyzer indicate the changes of ion and electron temperatures with solar zenith angles as discussed by the authors, indicating a constant heat flux into the electron gas at the ionopause which may be supplied by dissipation of energy by the whistler mode plasma waves and conduction of heat from the ionosheath through the mantle.
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Observation of the Venus mantle, the boundary region between solar wind and ionosphere
TL;DR: For three orbit paths of the Pioneer Venus orbiter, the interaction between the solar wind and the Venusian ionosphere has been studied as discussed by the authors, and the results of the retarding potential analyzer and the magnetometer are described for the boundary region.
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Thermal Structure and Major Ion Composition of the Venus Ionosphere: First RPA Results from Venus Orbiter.
TL;DR: 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.
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On the maintenance of the Venus nightside ionosphere: Electron precipitation and plasma transport
TL;DR: In this paper, the relative contributions of electron precipitation and transport of dayside plasma to the maintenance of the Venus nightside ionosphere during the long Venusian night are investigated based on simultaneous Pioneer Venus Orbiter Retarding Potential Analyzer measurements of suprathermal electron fluxes and plasma densities.