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Characteristics of Mini-Magnetospheres Formed by Paleo-Magnetic Fields of MarsThe intensely and non-uniformly magnetized crustal sources generate an effective large-scale magnetic field. In the Southern hemisphere the strongest crustal fields lead to the formation of large-scale mini-magnetospheres. In the Northern hemisphere, the crustal fields are rather weak and there are only isolated mini-magnetospheres. Re-connection with the interplanetary magnetic field (IMF) occurs in many localized regions. This may occur not only in cusp-like structures above nearly vertical field anomalies but also in halos extending several hundreds of kilometers from these sources. Re-connection will permit solar wind (SW) and more energetic particles to precipitate into and heat the neutral atmosphere. Electron density profiles of the ionosphere of Mars derived from radio occultation data obtained by the Radio Science Mars Global Surveyor (MGS) experiment are concentrated in the near polar regions. The effective scale-height of the neutral atmosphere density in the vicinity of the ionization peak has been derived for each of the profiles studied. The effective scale-heights have been compared with the crustal magnetic fields measured by the MGS Magnetometer/Electron Reflectometer (MAG/ER) experiment. A significant difference between the large-scale mini-magnetospheres and regions outside of them has been found. The neutral atmosphere is cooler inside the large-scale mini-magnetospheres. It appears that outside of the cusps the strong crustal magnetic fields prevent additional heating of the neutral atmosphere by direct interaction of the SW. The scale-height of the neutral atmosphere density derived from the experiment with the MGS Accelerometer has been compared with MAG/ER data. The scale-height was found to be usually larger than mean value near the boundaries of potential mini-magnetospheres and around cusps . It may indicate that the paleo-magnetic/IMF field re-connection is characteristic of the mini-magnetospheres at Mars.
Document ID
20030066610
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
N F Ness
(University of Delaware Newark, Delaware, United States)
A M Krymskii
(Rostov State Univ. Rostov-on-Don, USSR)
D H Crider
(Catholic University of America Washington D.C., District of Columbia, United States)
T K Breus
(Space Research Institute Moscow, Russia)
M H Acuna
(Goddard Space Flight Center Greenbelt, Maryland, United States)
D Hinson
(Stanford University Stanford, California, United States)
K K Barashyan
(Rostov State Univ. Rostov-on-Don, USSR)
Date Acquired
August 21, 2013
Publication Date
July 25, 2003
Publication Information
Publication: Sixth International Conference on Mars
Subject Category
Astrophysics
Report/Patent Number
3119
Meeting Information
Meeting: Sixth International Conference on Mars
Location: Pasadena, CA
Country: US
Start Date: July 20, 2003
End Date: July 25, 2003
Sponsors: Lunar and Planetary Institute
Funding Number(s)
CONTRACT_GRANT: NCC5-679
Distribution Limits
Public
Copyright
Portions of document may include copyright protected material.
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