Applications to upper atmosphere research

Quadrupole mass spectrometers on rockets and satellites allow in-situ measurements to be made in the upper atmosphere. The upper atmosphere measurements are made in the part of the atmosphere stretching from 80 km to the boundary with interplanetary space. The early history of mass spectrometry in the upper atmosphere is outlined. The techniques for density measurements of certain elements are discussed and also the various problems in obtaining spectra for neutral gases and ions. The different types of mass spectrometer used in upper atmosphere analysis are also considered. (B.D.)