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Near equality of ion phase space densities at earth, Jupiter, and SaturnEnergetic-ion phase-space density profiles are strikingly similar in the inner magnetospheres of earth, Jupiter, and Saturn for ions of first adiabatic invariant near 100 MeV/G and small mirror latitudes. Losses occur inside L approximately equal to 7 for Jupiter and Saturn and inside L approximately equal to 5 at earth. At these L values there exist steep plasma-density gradients at all three planets, associated with the Io plasma torus at Jupiter, the Rhea-Dione-Tethys torus at Saturn, and the plasmasphere at earth. Measurements of ion flux-tube contents at Jupiter and Saturn by the low-energy charged-particle experiment show that these are similar (for O ions at L = 5-9) to those at earth (for protons at L = 2-6). Furthermore, the thermal-ion flux-tube contents from Voyager plasma-science data at Jupiter and Saturn are also very nearly equal, and again similar to those at earth, differing by less than a factor of 3 at the respective L values. The near equality of energetic and thermal ion flux-tube contents at earth, Jupiter, and Saturn suggests the possibility of strong physical analogies in the interaction between plasma and energetic particles at the plasma tori/plasma sheets of Jupiter and Saturn and the plasmasphere of earth.
Document ID
19850037007
Document Type
Reprint (Version printed in journal)
Authors
Cheng, A. F. (Kansas Univ. Lawrence, KS, United States)
Krimigis, S. M. (Johns Hopkins University Applied Physics Laboratory, Laurel, MD, United States)
Armstrong, T. P. (Kansas, University Lawrence, KS, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1985
Publication Information
Publication: Journal of Geophysical Research
Volume: 90
ISSN: 0148-0227
Subject Category
LUNAR AND PLANETARY EXPLORATION
Funding Number(s)
CONTRACT_GRANT: NAGW-154
CONTRACT_GRANT: NASA TASK I
CONTRACT_GRANT: N00024-83-C-5301
Distribution Limits
Public
Copyright
Other