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Jaggers, C. H.

Publications and source records attributed to Jaggers, C. H..

Exposure of LDEF materials to atomic oxygen: Results of EOIM 3

The third Effects of Oxygen Atom Interaction with Materials (EOIM 3) experiment flew on STS-46 from July 31 to August 8, 1992. The EOIM-3 sample tray was exposed to the low-earth orbit space environment for 58.55 hours at an altitude of 124 nautical miles resulting in a calculated total atomic oxygen (AO) fluence of 1.99 x 10(exp 20) atoms/sq cm. Five samples previously flown on the Long Duration Exposure Facility (LDEF) Experiment M0003 were included on the Aerospace EOIM 3 experimental tray: (1) Chemglaze A276 white thermal control paint from the LDEF trailing edge (TE); (2) S13GLO white thermal control paint from the LDEF TE; (3) S13GLO from the LDEF leading edge (LE) with a visible contamination layer from the LDEF mission; (4) Z306 black thermal control paint from the LDEF TE with a contamination layer from the LDEF mission; and (5) anodized aluminum from the LDEF TE with a contamination layer from the LDEF mission. The purpose of this experiment was twofold: (l) investigate the response of trailing edge LDEF materials to atomic oxygen exposure, thereby simulating LDEF leading edge phenomena; (2) investigate the response of contaminated LDEF samples to atomic oxygen in attempts to understand LDEF contamination-atomic oxygen interactions. This paper describes the response of these materials to atomic oxygen exposure, and compares the results of the EOIM 3 experiment to the LDEF mission and to ground-based atomic oxygen exposure studies.

Jaggers, C. H.↗

Thermal control paints on LDEF: Results of M0003 sub-experiment 18

Several thermal control paints were flown on the Long Duration Exposure Facility (LDEF), including the white paints Chemglaze A276, S13GLO, and YB-71, and the black paint D-111. The effects of low earth orbit, which includes those induced by UV radiation and atomic oxygen, varied significantly with each paint and its location on LDEF. For example, samples of Chemglaze A276 located on the trailing edge of LDEF darkened significantly due to UV-induced degradation of the paint's binder, while leading edge samples remained white but exhibited severe atomic oxygen erosion of the binder. Although the response of S13GLO to low earth orbit is much more complicated, it also exhibited greater darkening on trailing edge samples as compared to leading edge samples. In contrast, YB-71 and D-111 remained relatively stable and showed minimal degradation. The performance of these paints as determined by changes in their optical and physical properties, including solar absorptance as well as surface chemical changes and changes in surface morphology is examined. It will also provide a correlation of these optical and physical property changes to the physical phenomena that occurred in these materials during the LDEF mission.

Jaggers, C. H.↗

Long Duration Exposure Facility experiment M0003: Deintegration/findings and impacts

The Long Duration Exposure Facility (LDEF) Experiment M0003 consists of 19 subexperiments from laboratories and contractor organizations and was designed to study the effects of the space environment on a large variety of spacecraft materials and components, both current and developmental. The experiment was housed in four LDEF trays and contained over 1250 specimens, two data systems, and two environment exposure control canisters. Nearly identical pairs of trays were located on the leading and trailing edges of LDEF. The materials in these trays span nearly all generic functions in spacecraft such as optics, thermal control, composites, solar power, and electronics. Effects of the space environment, such as vacuum, ultraviolet, atomic oxygen, meteoroids and debris, thermal cycling, and synergistic effects on various samples, will be described. Summaries of the on-board data will be presented.

Meshishnek, M. J.↗

Long Duration Exposure Facility experiment M0003 deintegration/findings and impacts

The Aerospace Corporation LDEF Experiment M0003 was designed to study the effect of the space environment on a large variety of spacecraft materials and components, both current and developmental. The experiment was housed in four LDEF trays and contained over 1200 specimens, two data systems, and two environment exposure control canisters. Effects of the space environment such as vacuum, ultraviolet, atomic oxygen, meteoroid and debris, thermal cycling and synergistic effects on various samples are described, and summaries of the board data are presented.

Meshishnek, M. J.↗