HR: 1340h
AN: SA13A-1115    [Abstracts]
TI: Effects in the Martian Ionosphere Caused by the Solar Cycle Variation of the EUV Flux and Solar Wind Dynamic Pressure
AU: Krymskii, A M
EM: amkrym@yahoo.com
AF: Rostov State University, Department of Astrophysics ul. Zorge 5, Rostov-on-Don, 344104 Russian Federation
AU: Breus, T K
EM: breus@space.ru
AF: Space Research Institute, IKI, Russian Academy of Sciences, Profsoyuznaya 84/32, Moscow, GSP-7 Russian Federation
AU: * Ness, N F
EM: nfness@udel.edu
AF: University of Delaware, Bartol Research Institute 217 Sharp Laboratory, Newark, DE 19716 United States
AU: Crider, D H
EM: dcrider@lepvax.gsfc.nasa.gov
AF: The Catholic University of America, Department of Physics, Washington, DC 20064 United States
AU: Hinson, D P
EM: hinson@rocc.stanford.edu
AF: Stanford University, Department of Electrical Engineering, Stanford, CA 94305-9515 United States
AB: Solar wind electrons can penetrate the Martian ionosphere outside of the regions of the strong crustal fields. Sometimes, in the northern hemisphere of Mars, the peak electron density does not follow the EUV radiation flux variations, as was found recently. The SW dynamic pressure is assumed to be high in such periods. The SW dynamic pressure reaches its maximum several years after solar activity begins to decline. Thus, following the solar activity maximum, the combination of decreasing EUV flux and increasing SW dynamic pressure may result in conditions such that the peak electron density is not correlated with the EUV radiation flux in that period. For the time period November 2000 - December 2002, electron density profiles have been derived from MGS radio occultation data. We study the correlation between the EUV flux using the E10.7 index and the adjusted peak electron density. Next, we use ACE SWEPAM data (daily averages) to study anti-correlation of the SW dynamic pressure and EUV radiation flux (E10.7 index) in this same time period. Finally, we validate the assumption that the effects of an increasing SW dynamic pressure can reduce any apparent correlation between the peak electron density and EUV radiation flux during the period following solar activity maximum.
DE: 7835 Magnetic reconnection
DE: 5440 Magnetic fields and magnetism
DE: 6225 Mars
DE: 2162 Solar cycle variations (7536)
DE: 2459 Planetary ionospheres (5435, 5729, 6026, 6027, 6028)
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting