NASA Polar Radiant Energy in the Far-InfraRed Experiment (PREFIRE) is an active Earth-observation program built around two CubeSats launched in May and June 2024. The pair measures far-infrared radiation emitted by the Arctic and Antarctic, helping quantify polar heat loss and improve models of sea-ice loss, ice-sheet melting, weather, and climate; NASA reports the mission is extended through at least September 2026.