Atmospheric Waves Experiment (AWE) Thermal Control System Review of On-Orbit Thermal Performance

This paper reviews the Atmospheric Waves Experiment (AWE) detector thermal control system’s (TCS) performance for over two years of operation on the Internation Space Station (ISS). The TCS employs active thermal control for the InGaAs detectors with thermoelectric coolers (TEC). Each of the four detectors are controlled by a dedicated TEC at a nominal setpoint of -30°C, with heat transported away via low-mass, high-conductance pyrolytic graphite sheet (PGS) thermal straps into a nickel-plated copper conductor bar. A bi-directional radiator with Silver Teflon ensures an unobstructed view that can radiate the heat away to space. Titanium isolators decouple the detectors from the telescope structure and maintain focus over the entire operational temperature range. Details of the thermal architecture are discussed in detail, focusing on the detector thermal zone TCS. TEC details, integration, characterization, and safety limits are also discussed. On-orbit telemetry shows detector temperatures remain within allowable flight temperature limits throughout the mission, with TEC control maintaining tight stability near the setpoint (~0.04°C). Year-over-year comparisons highlight operational differences and environmental drivers. Overall system thermal performance is robust under the extreme, time-varying orbital conditions on the ISS.