Downloaded from https://www.everyspec.com MIL-STD-81OC 1. Solar constant. .Solarconstant’ is the rate,at which solar radiation is received outside the Earth’s atmosphere on a surface normal to the incident radiation and at the Earthis mean distance from the ,.Sun. m. Solar absorptance. This relates the absorptance of (U5) a test item irradiated with a solar simulator to the absorptance the test item would experience from the Sun. 6. SUMMARY. The following details shall be as specified in t,heequipment spec-on: a. Pretest data required (see General Requirements, 3.2). b. All information necessary for the completion of 3.la through 3.lb. . 517.2-13 METHOD517.2 #