18 December 1992 Optical properties of water released in low earth orbit
Author Affiliations +
Results of an analysis of intensified video photographs of a twilight venting of excess water from Space Shuttle are presented. The particle sizes, densities, and temperatures derived from the visible data are applied in estimating UV and IR radiances of the ice/vapor-containing volumes near Shuttle Orbiter, using a recently developed gas-transport/excitation model. The mean radius of the fragmentation-product droplets is 0.13 +/- 0.02 cm. This radius decreases by less than 5 percent over a 2.5-km initial flight path, and these particles survive for several hr. In the UV, intensities of radiation from the fragmentation particles fall off with decreasing wavelength due to the decrease in spectral irradiance of sunlight. In the IR, the mm particles are optically thick, while ice particles not greater than 0.3 micron are inefficient scatterer-radiators, except near 2.7 microns. The large-droplet component thus dominates the radiances even in projections to distant sensors, suppressing the severe spectral structure characteristic of the small droplets.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
James A. Gardner, David L. A. Rall, Christian A. Trowbridge, Irving L. Kofsky, Rodney A. Viereck, Edmond Murad, Charles P. Pike, Alvin T. Stair, and Alireza Setayesh "Optical properties of water released in low earth orbit", Proc. SPIE 1754, Optical System Contamination: Effects, Measurement, Control III, (18 December 1992); doi: 10.1117/12.140725; https://doi.org/10.1117/12.140725


Back to Top