Reflectances of CO2 and H2O Cryodeposits at Solar Wavelengths
Final rept. Jan 1970-Jun 1971
ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN
Pagination or Media Count:
A careful study of the reflectances of carbon dioxide and water cryodeposits was made in a vacuum integrating sphere in the solar wavelength range 0.30 to 2.55 micrometers. These deposits were formed on liquid-nitrogen-cooled black epoxy paint and polished stainless steel substrates. The reflectances of these deposits were studied while varying the deposit thickness, view angle, and wavelength. The reflectance dependence on thickness was also predicted theoretically and the values obtained were in excellent agreement with the experimentally determined values. Most of the water deposits studied were of amorphous structure, but upon warming, the deposits crystallized resulting in a significant change in the reflectance. No structural changes were observed when the carbon dioxide frosts were warmed. From the results of this study, conclusions are drawn with regard to the application of these findings to several current problems.