The Access of Energetic Charged Particles to Satellite Altitudes.
Abstract
Primary cosmic ray particles are able to arrive at earth satellites, orbiting at altitudes of only a few hundred kilometers, from zenith angles considerably larger than that of the local horizon. The largest zenith angles at which below horizon access is possible have been investigated for a series of satellite altitudes between 400 km and 3600 km. The largest accessible zenith angle found at 400 km is 150 degrees. The angle becomes larger with increasing altitude, reaching 180 degrees (the nadir direction) at 1250 km. Particles arrive at these large zenith angles from a range of westerly directions. At altitudes above 1250 km, particles passing beneath the satellite with their paths curving upwards are able to arrive at large zenith angles from easterly directions. The ranges of zeniths and azimuths involved are altitude dependent. Largest zenith angles of arrival can be interpolated between azimuths, inlimited azimuthal ranges only. These ranges are centred about the azimuth (270 - latitude). The range of reliable interpolation is altitude dependent, becoming larger at higher altitudes. Originator-supplied keywords included: Cosmic Rays; Geomagnetic Field; Energetic Cahrged Particles; Radiation to Satellites.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 05, 1984
- Accession Number
- ADA150799
Entities
People
- J. E. Humble
Organizations
- University of Tasmania