KIRTLAND AFB, N.M. (AFRL) – The Air Force Research Laboratory, or AFRL, launched the Space Power InfraRed Regulation and Analysis of Lifetime, or SPIRRAL, experiment, Nov. 4, 2024. SPIRRAL, flown by AFRL through the DoD Space Test Program, will characterize the performance of Variable Emissivity Materials, or VEMs, an approach toward solving thermal challenges for space vehicles while on-orbit.
VEMs are surface finishes that act like color-changing paints, however, the changes in coloration are only in the infrared light spectrum and are not visible to the human eye. VEMs can either reject or retain heat depending on the temperature being experienced. When the VEMs are hot, the material’s optical properties change to reject heat; when they are cold, they retain heat, effectively reducing temperature extremes.