Satellite Sensing of Low Energy Plasma Bulk Motion.
Abstract
Low-energy plasma motion in the ionospheric-magnetispheric region may be measured directly using an array of planar ion sensors on a spin-stabilized satellite. In the equatorial, low-altitude (below 400 km), 'zero plasma motion' region, the relative plasma flow is due to spacecraft velocity only; the sensors give information concerning the attitude of the spacecraft in the plasma. In the polar regions or at higher altitudes, plasma flow is important, and the attitude and ephemeris data of the spacecraft in an external system are necessary for the determination of plasma flow in this system. We outline a sensor system that measures the flow of low-energy plasma and proceed to define all the additional information required to operate in the moving plasma region, together with the coordinate transforms this involves. Corrections are derived for three factors that arise in the practical application of such an instrument: (1) the offset between spacecraft geometric axes and the actual alignment of the sensors as mounted; (2) the offset between spacecraft geometric axes and the spin-sxis location achieved in flight; and (3) the separation of the spacecraft velocity vector from the spacecraft spin plane. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 07, 1976
- Accession Number
- ADA033899
Entities
People
- M. Smiddy
- P. J. L. Wildman
- S. T. Lai
Organizations
- Air Force Research Laboratory