HR: 0800h
AN: SA51B-1142 [Abstracts]
TI: Calculating Martian Auroral Emission including Strong Field Gradients and Accelerated Electron
Spectra
AU: * Fillingim, M O
EM: matt@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AU: Peticolas, L M
SA51B-1142
AF: Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AU: Lillis, R J
SA51B-1142
AF: Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AU: Brain, D A
SA51B-1142
AF: Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AU: Halekas, J S
SA51B-1142
AF: Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AU: Lin, R P
SA51B-1142
AF: Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AU: Lummerzheim, D
SA51B-1142
AF: Geophysical Institute, University of Alaska, 903 Koyukuk Drive, Fairbanks, AK 99775-7320
United States
AU: Bougher, S W
SA51B-1142
AF: Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2455 Hayward Street,
Ann Arbor, MI 48109-2143
United States
AB:
Auroral emission has been detected at every planet in the solar system which has a known global magnetic field and a
substantial atmosphere. Recent Mars Express observations have shown that auroral emission also exists on Mars, which lacks a
global magnetic field but does have localized regions of strong magnetic crustal sources. Additionally, accelerated
electron spectra, reminiscent of those observed in Earth's auroral region, have recently been found in data from Mars Global
Surveyor. These recent developments have prompted us to revisit the question of auroral emission on Mars. Previous
calculations of auroral emission on Mars have neglected the effects of strong magnetic field gradients associated with
converging fields near localized crustal sources. Also, previous calculations used typical sheath or tail electron spectra
rather than the newly discovered accelerated spectra. We use observed MGS electron spectra as input into a new coupled
electron transport and emission model which includes realistic magnetic field gradients. We analyze the effect the strong
gradients have on the electron intensity in the upper atmosphere and the resulting excitation and ionization rates and
emissions. In addition, we explore the range of excitation and ionization rates and emissions due to the different classes
of observed electron spectra from sheath-like, to highly accelerated, to those observed during solar energetic particle
events.
UR: http://sprg.ssl.berkeley.edu/matt/AGU2005/
DE: 0358 Thermosphere: energy deposition (3369)
DE: 2455 Particle precipitation
DE: 5408 Aurorae and airglow
DE: 5435 Ionospheres (2459)
DE: 6225 Mars
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005