作者: L. H. Brace , R. F. Theis , W. R. Hoegy , J. H. Wolfe , J. D. Mihalov
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摘要: Measurements of electron density and temperature by the Pioneer Venus orbiter probe (OETP) are used to describe dynamic behavior ionosphere begin relate this complex variations in solar wind ionosheath magnetic field, parameters that also measured instruments. The average ionopause height rises from about 330 km at subsolar point 700 dusk terminator 1000 dawn terminator, both cases exhibiting a stronger dependence upon zenith angle than reported Venera 9 10 occultation data. on dayside tends expand contract with changes pressure, becoming asymptotic 290 pressures above 4 × 10−8 dyn/cm² rising over for below 5 10−9 dyn/cm². after correction angle, agrees approximately field pressure applied ionopause, confirming earlier suggestions is conveyed primarily rather shocked plasma. On nightside much more highly variable, sometimes falling 200 or 3500 km. present orbit does not permit true configuration be measured. Within itself, we find extreme spatial irregularities form holes, horizontally stratified layers, detached plasma clouds, dual regions low density. A scenario developed process ion pickup terms discontinuities inducing wavelike structure which then penetrated fields remove ionospheric impulsively clouds. energy released may responsible elevated temperatures observed ionosphere.