Venusian ionopause and bow shock anisotropy and variations influenced by IMF, solar wind, and UV-flux
Abstract
The crossings of Venusian bow shock BS by Venera 4 6 9 10 Mariner 5 10 Pioneer Venus and Galileo spacecrafts revealed several peculiarities of this boundary Its terminator pre-terminator position turned to be weakly dependent on solar wind parameters variations within specific phase of solar cycle Venera 9 10 while strongly variable within solar activity cycle Pioneer Venus Bow shock terminator position anisotropy was revealed for quasi-perpendicular upstream solar wind flows Venera 9 10 Pioneer Venus and theoretically expected variation of post-terminator BS position with change of the Mach cone angle was also found Galileo These and others peculiarities of Venusian bow shock are quantitatively refined with the aid of recent analytic BS modeling approach which additionally permitted to reveal the dawn-dusk bow shock terminator asymmetry New approach permitted also to clarify its subsolar position variations and to study Venusian ionopause and exospheric plasma pressure variations within solar cycle This work was partially supported by RFBI grant 03-02-20006-BNTS-a and Program OFN 16 of the Department of physical sciences of Russian Academy of Sciences
- Publication:
-
36th COSPAR Scientific Assembly
- Pub Date:
- 2006
- Bibcode:
- 2006cosp...36..997V