Onset and development of Kelvin-Helmholtz instability at the Venus ionopause

Journal Article · Tue Dec 30 00:00:00 EST 1980 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA085iA13p07697· OSTI ID:6499500

Wolff, R S; Goldstein, B E; Yeates, C M

We investigate the Kelvin-Helmholtz instability at the Venus ionopause resulting from the flow of the (shocked) solar wind tangential to the ionopause for the case where the interplanetary field is oriented normal to the direction of flow. It is found that gravity stabilizes the long wavelength perturbations, and the finite thickness of the boundary layer stabilizes short wavelength modes. The magnetic 'gyroviscosity' due to finite Larmor radius effects either destabilizes the boundary or stabilizes it according to whether the solar wind electric field points away from or toward the ionosphere. For solar wind and ionosphere plasma parameters consistent with Pioneer Venus observations we find that the instabilities with the greatest growth rates (shortest growth times) have wavelengths of approx.50--150 km and growth times of approx.0.5 to several seconds. In addition, we show how distortion of the ionopause by Kelvin-Helmholtz instability might lead to the formation of magnetic 'flux ropes' inside the ionosphere as well as ionospheric 'bubbles' embedded in the solar wind.

• Research Organization: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91103
• OSTI ID: 6499500
• Journal Information: J. Geophys. Res.; (United States), Vol. 85:A13
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
VENUS PLANET
PLANETARY IONOSPHERES
HELMHOLTZ INSTABILITY
INTERPLANETARY MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
PIONEER SPACE PROBES
PLASMA MACROINSTABILITIES
SOLAR WIND
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
MAGNETIC FIELDS
MECHANICS
PLANETS
PLASMA INSTABILITY
SOLAR ACTIVITY
SPACE VEHICLES
VEHICLES
640107* - Astrophysics & Cosmology- Planetary Phenomena