On the momentum transfer of the solar wind to the Martian topside ionosphere

Journal Article · Sat Jun 01 04:00:00 EDT 1991 · Geophysical Research Letters (American Geophysical Union); (United States)

DOI:https://doi.org/10.1029/90GL02604· OSTI ID:5190933

Lundin, R; Norberg, O ^[1]; Dubinin, E M; Pissarenko, N; Barabash, S W ^[2]; Koskinen, H ^[3]

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1. Swedish Inst. of Space Physics, Kiruna (Sweden)
2. Space Research Inst., Moscow (USSR)
3. Finnish Meteorological Inst., Helsinki (Finland)

Hot plasma measurements from the Soviet Phobos-2 spacecraft in the Martian magnetosphere suggests that the solar wind interaction with Mars is cometary-like, with mass loading of the solar wind and ion pick-up occuring also outside the subsolar bow-shock. The interaction is characterized by a pronounced decrease of the solar wind speed inside what has been termed the mass-loading boundary (MLB). Well outside the MLB, the ion pick-up process acts in a normal sense. There ions pick up approximately the solar wind velocity - independent of mass. Inside the MLB, the momentum loss of solar wind ions is more pronounced - heavy ions of Martian origin taking up most of the solar wind ion maximum flux. The heavy mass-loading of solar wind ions in the innermost part of the Martian boundary layer (near the magnetopause) leads to a loaded ion pick-up. The process can be understood as internal loading of an MHD-dynamo, propelled by a driver plasma - the solar wind. The ASPERA ion composition and momentum data is consistent with such a pick-up process. Inside the magnetopause ions of Martian origin are accelerated up to energies close to those of the solar wind protons. The authors propose two types of acceleration processes, one similar to that acting within the Earth's auroral acceleration region (acting in the presence of an ambient magnetic field), another pick-up process acting within a limited spatial region.

• OSTI ID: 5190933
• Journal Information: Geophysical Research Letters (American Geophysical Union); (United States), Journal Name: Geophysical Research Letters (American Geophysical Union); (United States) Vol. 18:6; ISSN 0094-8276; ISSN GPRLA
• Country of Publication: United States
• Language: English

Related Subjects

640107* -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELERATION
AURORAL ZONES
CHARGED PARTICLES
EARTH ATMOSPHERE
INTERACTIONS
IONIC COMPOSITION
IONS
MARS PLANET
MOMENTUM TRANSFER
ORIGIN
PLANETARY IONOSPHERES
PLANETS
SATELLITES
SHOCK WAVES
SOLAR ACTIVITY
SOLAR WIND