Upstream waves at Uranus

Journal Article · Thu Mar 01 04:00:00 EST 1990 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA095iA03p02273· OSTI ID:5182330

Russell, C T ^[1]; Lepping, R P ^[2]; Smith, C W ^[3]

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1. Univ. of California, Los Angeles (United States)
2. NASA Goddard Space Flight Center, Greenbelt, MD (United States)
3. Univ. of Delaware, Newark (United States)

Since the Mach number of the solar wind increases with increasing heliocentric distance, the ratio of thermal to magnetic pressure, or beta, of the Uranian magnetosheath is expected to be much higher than in the terrestrial magnetosheath. Consistent with this expectation the magnetosheath is observed to be extremely turbulent, and one may expect many particles to leak back upstream into the solar wind and/or be scattered from the bow shock. In accord with the expected presence of backstreaming particles, waves of the type associated with terrestrial backstreaming particles are seen outbound along the trajectory of Voyager in the pre-shock solar wind with frequencies close to 10{sup {minus}3} Hz. The wave frequency is close to that expected for upstream waves based on measurements closer to the Sun. Upstream from the bow shock the magnetic field was found to be much weaker than expected from observations in the inner solar system. The cause of this depression is unlikely to be the upstream particles; rather the cause is probably intrinsic to the solar wind such as reconnection across the heliospheric current sheet.

• OSTI ID: 5182330
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 95:A3; ISSN JGREA; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

640107* -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COMPARATIVE EVALUATIONS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
EVALUATION
INTERACTIONS
LEAKS
MACH NUMBER
MAGNETIC FIELDS
MAGNETIC RECONNECTION
MAGNETOSHEATH
PLANETS
SCATTERING
SHOCK WAVES
SOLAR ACTIVITY
SOLAR WIND
SPACE VEHICLES
URANUS PLANET
VEHICLES
VELOCITY
VOYAGER SPACE PROBES