Abstract Pioneer Venus Orbiter Electron Temperature Probe (OETP) measurements of hundreds of bow shock and ionopause crossings have been employed to describe the configuration of these two boundaries and their variations in response to changes in solar wind pressure. The average bowshock configuration is well represented by an Archimedian hyperboloid whose altitude at the subsolar point is 0.46 Venus radii, a value slightly greater than that derived from Pioneer Venus magnetometer data using a fit to a general conic section. The average bow shock configuration exhibits a high degree of azimuthal symmetry near the terminator. The orbit to orbit variability of the shock location is unexpectedly large, having a standard deviation of about 10% (0.2 Rv). This is comparable to the variability in the dayside ionospause radius at 70–80° solar zenith angle, a region of the obstacle that is coupled to the high latitude shock region observed by Pioneer Venus. There is a tendency for the bowshock and the ionopause to expand and contract simultaneously, but the weakness of their orbit by orbit correlation suggests that the ionopause of Venus is not the only obstacle to the solar wind. Other processes such as photoion pickup and charge exchange with neutrals would appear to be important in diverting the solar wind plasma around the planet.
The Venus ionosphere as an obstacle to the solar wind
Advances in Space Research ; 1 , 1 ; 47-60
1981-01-01
14 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Elsevier | 1985
|NTRS | 1985
|Global hybrid model of the solar wind interaction with the Venus ionosphere: ion escape processes
Online Contents | 2004
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