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Rogers, J. F.

Publications and source records attributed to Rogers, J. F..

Estimation of outgassing from an expended apogee motor and its effects on spacecraft surfaces

An experimental and theoretical investigation was carried out to evaluate the degradation of the solar cells and other sensitive surfaces of a spacecraft, resulting from the molecular outgassing of an expended solid propellant apogee motor. The motor, following its burnout, is retained by the spacecraft and is a source of gases and particulates which will be released mainly by the unburned propellant-to-casing insulation. The deployment of the solar array within a few minutes after the motor burn results in the interception and reflection to the surfaces of the spacecraft of the molecular outgassing and particulates. Various methods, based on some experimental data, were used to analytically assess the magnitude of the outgassing from the engine.

Scialdone, J. J.↗

ATS-6 - Quartz-Crystal Microbalance

The Quartz-Crystal Microbalance Experiment provided data on the possible return of contaminants to the exterior surfaces of the spacecraft. The experiment measures the change in resonant frequency of the crystal due to deposition of material on the surface. There has been no mass accretion corresponding to the firing of hydrazine thrusters to unload the spacecraft momentum wheels. There have been accretions corresponding to the firing of the cesium ion engines.

Rogers, J. F.↗

Data from a synchronous altitude satellite quartz crystal microbalance monitor

Results of one year's operation in orbit of the Quartz Crystal Microbalance Monitor on the ATS-6 satellite are presented. The data indicate a general decreasing trend for the first four and one-half months in orbit. At that time, a sudden increase in beat frequency occurred; this correlates in time with the firing of the North Cesium Ion Engine. A general increase in beat frequency is evidenced since that time. Laboratory tests conducted to investigate the phenomenon are described.

Rogers, J. F.↗