Abstract
Solar spectral irradiance measurements were made from NASA’s Convair 990 research aircraft using a Leiss double prism monochromator and a GSFC modified Eppley Mark V radiometer. Six flights were made over the Pacific and western United States at an altitude of 11.58 km. Excellent agreement is noted between the two instruments through a wavelength range of 0.3–1.1 μ, even though they are optically and electronically dissimilar. Instrument calibrations were performed in flight using an NBS type quartz–iodine standard of spectral irradiance. Extrapolation to zero air mass was facilitated by the fact that at 11.58 km the aircraft was above 80% of the permanent gases of the atmosphere and more importantly above 99.9% of the water vapor and all the atmospheric pollutants. The resulting solar spectral curves differ significantly from Johnson’s in several regions. Solar constant measurements made with other flight instruments resulted in a value of 0.1351 W cm−2, which is about 3.3% less than Johnson’s, but is in good agreement with recently published values of Drummond, Laue, and others.
© 1970 Optical Society of America
Full Article | PDF ArticleMore Like This
M. P. Thekaekara, R. Kruger, and C. H. Duncan
Appl. Opt. 8(8) 1713-1732 (1969)
John C. Arvesen, Roy N. Griffin, and B. Douglas Pearson
Appl. Opt. 8(11) 2215-2232 (1969)
M. Bader and C. B. Wagoner
Appl. Opt. 9(2) 265-270 (1970)