M. Cecilia Gaposchkin. Review of "The Book of Kings: Art, War, and the Morgan Library’s Medieval Picture Bible" by William Noel and Daniel Weiss.

Calculation of Resident Space Object Color Temperature and Emissivity-Area from MSX SPIRIT III Infrared Data: Emissive Reference Sphere Results

“…The sphere was sunlit when deployed but crossed the terminator at ~1600 seconds after deployment; the temperature of the sphere rose while sunlit and fell after the terminator crossing, as expected. The computed color temperatures are reasonable; a sunlit sphere in thermal equilibrium, with oc=£, will have an equilibrium temperature of 278.5 °K 19 . It is easy to show, using the model described in Section 3, that due to the proximity of the sphere to the Earth, the sphere will warm to an equilibrium temperature of ~287.5 °K; this is similar to the temperature attained by the sphere before it entered eclipse.…”