Correlative satellite measurements of atmospheric mass density by accelerometers, mass spectrometers and ionization gauges
Document ID: 47
Marcos, F. A.1
Philbrick, C. Russell1
Rice, C. J.2
1 USAF, Geophysics Laboratory, Hanscom AFB, Bedford, MA, U.S.A.
2 Aerospace Corporation, Los Angeles, CA, U.S.A.
Abstract
A complement of experiments to monitor atmospheric density was flown as part of the payload on an Air Force research satellite. This paper describes neutral gas mass densities as measured by the following instruments on this satellite: an electrostatic accelerometer, an RF quadrupole mass spectrometer and a cold-cathode ionization gauge. Mass densities are determined from aerodynamic drag as recorded by the accelerometer, from summation of the densities of atmospheric constituents directly sampled by the mass spectrometer and from ambient pressure measurements by the ionization gauge operated simultaneously. Results obtained during 1974 between 160 and 250 km altitude were studied to compare the absolute densities obtained by the different methods. The results agree within experimental error, although there is some evidence that a systematic height dependence exists.
Keywords: thermosphere, accelerometer, mass spectrometer data, gas composition, satellite instruments