Action of the neutral atmosphere and charged particles on the movement of a satellite - application to LAGEOS.
Abstract
The effects of neutral and charged particle drag on the motion of the Lageos geodesic satellite are calculated in an attempt to explain the observed secular decrease, amounting to 1.1 mm/day, in the semimajor axis of the satellite. Expressions are presented for the electric charge and potential of a satellite moving through an ionized medium, and for the effective cross section for satellite-charged particle collisions in the presence of spacecraft charging, which is greater than the spacecraft cross section. Satellite braking due to neutral and charged particle collisions and exchanges of momentum with noncolliding particles is then estimated as a function of particle thermal velocities. Application of the formulas obtained to Lageos using model estimations of the concentrations of neutral hydrogen, H(plus), He(plus) and O(plus) in the atmosphere at satellite altitude results in an acceleration corresponding to about half that actually observed. It is noted that uncertainties in the values used to model exospheric composition may be the source of this discrepancy.
- Publication:
-
Annales de Geophysique
- Pub Date:
- March 1981
- Bibcode:
- 1981AnG....37..247M
- Keywords:
-
- Atmospheric Effects;
- Ionized Gases;
- Lageos (Satellite);
- Neutral Gases;
- Satellite Drag;
- Satellite Orbits;
- Spacecraft Charging;
- Charged Particles;
- Electric Potential;
- Exosphere;
- Orbital Elements;
- Particle Collisions;
- Artificial Satellites:Earth Atmosphere