HR: 1340h
AN: SH43A-1139    [Abstracts]
TI: Magnus Force in the Venus Ionosphere
AU: * Perez-de-Tejada, H A
EM: perezdet@igeofcu.unam.mx
AF: Institute of Geophysics, UNAM, Ciudad Universitaria, Mexico, D F 04510 Mexico
AB: The retrograde super-rotation motion of the Venus ionosphere is included in a study of the configuration of the ionospheric trans-terminator flow by using a fluid-dynamic interpretation of the interaction that takes place between both flow motions. It is argued that the interaction leads to a fluid dynamic force (Magnus Force) that produces an overall (~10°) dawn-ward deflection of the trans-terminator flow which is comparable to that implied from the PVO observations. The Magnus Force results from a pressure difference that is set across the planet by the difference in the speed of the plasma when both the rotation motion and the trans-terminator flow are in the same sense (dusk side terminator) to that where both motions are opposite to each other (dawn side terminator). The dawn-ward directed deflection of the ionospheric plasma in the trans-terminator flow also deviates the plasma channels (which serve to account for the ionospheric holes) that extend downstream from the magnetic polar regions, and is responsible as well for the position of the electron density profiles with an upper ionospheric plateau that are seen near the midnight plane. The effects of the Magnus Force are also related to the strong difference in the ionopause altitude observed between the dusk and the dawn side terminator (with higher altitudes seen in the dawn side) and to the larger ionospheric trans-terminator flow speeds measured by the dawn side.
DE: 1060 Planetary geochemistry (5405, 5410, 5704, 5709, 6005, 6008)
DE: 2154 Planetary bow shocks
DE: 2459 Planetary ionospheres (5435, 5729, 6026)
DE: 6295 Venus
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005