HR: 15:50h
AN: SA33C-08    [Abstracts]
TI: Angular Electron Distributions at Mars and Venus
AU: * Brain, D A
EM: brain@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Luhmann, J G
EM: jgluhmann@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Halekas, J S
EM: jazzman@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Mitchell, D L
EM: mitchell@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Lin, R P
EM: rlin@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Barabash, S
EM: stas@irf.se
AF: IRF, PO Box 812, Kiruna, SE-981 28, Sweden
AU: Zhang, T
EM: tielong.zhang@oeaw.ac.at
AF: IWF, Schmiedlstrasse 6, Graz, 8042, Austria
AU: Frahm, R
EM: rfrahm@swri.edu
AF: Southwest Research Institute, PO Drawer 28510, San Antonio, TX 78228, United States
AU: Winningham, D
EM: dwinningham@swri.edu
AF: Southwest Research Institute, PO Drawer 28510, San Antonio, TX 78228, United States
AB: Suprathermal electron measurements have been recently made at both Venus and Mars by several spacecraft. Directional information in the form of pitch angle distributions are particularly useful because they allow us to probe magnetic field topology near planets, as well as the physical processes affecting plasma populating magnetic flux tubes. We will present angular electron distributions measured at both Mars and Venus. We analyze measurements made by the magnetometer and electron reflectometer (MAG/ER) on Mars Global Surveyor over a period of more than six years to identify the locations of open and closed magnetic field lines near Mars, and variability with respect to solar wind pressure and the direction of the interplanetary magnetic field. At Venus we discuss the utility of electron angular distributions for determining when draped solar wind magnetic field lines intersect the collisional atmosphere, and present recent progress made toward construction of pitch angle distributions from the Venus Express magnetometer and electron sensor (MAG and ASPERA-4 ELS).
DE: 5421 Interactions with particles and fields
DE: 5435 Ionospheres (2459)
DE: 6225 Mars
DE: 6295 Venus
DE: 7807 Charged particle motion and acceleration
SC: SPA-Aeronomy [SA]
MN: 2007 Joint Assembly