Metallic and Oxidized Aluminum Debris Impacting the Trailing Edge of the Long Duration Exposure Facility (LDEF)

摘要: 2 , T.H. SEE and D.J. KESSLER 3 Abstract. A total of 87 microcraters >30 µm in diameter that were found gold substrates exposed on the trailing edge non-spinning Long Duration Exposure Facility (LDEF) yielded analyzable projectile residues their interiors. Using qualitative SEM-EDS analysis methods, some 60 these craters formed by natural cosmic-dust particles, while 27 (31%) assigned to orbital debris (H¨ et al., 1993). The far majority orbital-debris impacts, 24 (89%) events, contained only aluminum X-ray spectra. present study evaluates aluminum-rich detail employs a windowless detector, which permits for low-Z elements specifically oxygen. This makes it possible discriminate between oxidized (Al2O3) metallic (Al) projectiles from dramatically different sources, former produced during solid-fuel rocket firings, latter resulting explosively or collisionally disrupted spacecraft. Of analyzed with 13 (54%) Al2O3 11 (46%) structurally disintegrated Al metal. preferentially occur smaller craters, all 35 µm, thus >60 µm. These findings clearly establish solid-rocket exhaust as well debris, exist low-inclination, high-eccentricity orbits sufficient quantities they must be accounted models describing future population at typical Shuttle Space Station altitudes.