Accession Number : AD0824336

Title :   SATELLITE MEASUREMENTS OF THE INTERACTION OF SURFACES WITH THE UPPER ATMOSPHERE.

Descriptive Note : Technical rept. Jun 63-Aug 67

Corporate Author : GENERAL DYNAMICS/CONVAIR SAN DIEGO CA SPACE SCIENCE LAB

Personal Author(s) : McKeown, D. ; Fox, M. G. ; Valerio, J. I. ; Miller, J. H.

Report Date : DEC 1967

Pagination or Media Count : 58

Abstract : Results are given on rarefied gas-surface interaction measurements made on satellites orbiting in the upper atmosphere. Sputtering erosion of Au and Ag surfaces by N2 impacts at 9 eV was less than 50 A/yr at 200 km. From the sputtering data, a theoretical model of sputtering was developed. Tests of a new type of energy transfer probe, using temperature sensors, were made on the SNAPSHOT satellite. Results showed the probe can detect energy transfer rates of 20 micro W/cm squared. The probe can be used to measure satellite drag at altitudes up to 600 km where the atmospheric density is great enough to produce measurable heating. Satellite instrumentation for measuring electron ejection of 10 to the-9th A/cm squared from surfaces by neutral gas impacts was built and tested.

Descriptors :   (*UPPER ATMOSPHERE, INTERACTIONS), (*SCIENTIFIC SATELLITES, UPPER ATMOSPHERE), (*SPUTTERING, UPPER ATMOSPHERE), IMPACT, MOLECULAR BEAMS, EROSION, SOLAR RADIATION, GOLD, SILVER, SURFACE PROPERTIES, SPACE ENVIRONMENTS.

Subject Categories : Atmospheric Physics
      Fabrication Metallurgy
      Particle Accelerators

Distribution Statement : APPROVED FOR PUBLIC RELEASE