The Determination of the Spacecraft Contamination Environment

Abstract : This report details our efforts in the determination of the on-orbit environment surrounding spacecraft. The research was performed for the Spacecraft Interactions Branch of the Space Physics Division of the Air Force Geophysics Laboratory. This report includes contributions from our subcontractors EKTRON Applied Imaging and Miranda Laboratories. The multilayer project consisted of three major tasks: a literature survey, preparation for the data of the Particle Analysis Cameras for Shuttle (PACS), and the analysis of the data to create a model of the orbital particulate environment. During the literature search we discovered that many observations were presented with little or no insight provided. Physical Sciences Inc. (PSI) therefore undertook a critical review of the data in an attempt to reconcile seemingly contractory observations and provide needed understanding of the variety of unexpected processes occurring above spacecraft surfaces in low-earth orbit. We were able to make contributions to the understanding of the neutral molecular contamination cloud; the modifications of the ionic environment; the optical contamination glow; and the earlier observations of particulates. Keywords: Contamination; Optical environment; Low earth orbit; Spacecraft glow particulates; Space shuttle; Chemiluminescence; Space environments; Manned spaceflight.