Passive microwave atmospheric sounder on a CubeSat performing science-quality observations for nearly 2 years: Temporal Experiment for Storms and Tropical Systems Demonstration (TEMPEST-D) mission

The Temporal Experiment for Storms and Tropical Systems Demonstration (TEMPEST-D) mission is the first CubeSat-based multi-frequency microwave sounder to provide global data over a sustained period. The mission was designed to demonstrate on-orbit capabilities of a five-frequency millimeter-wave radiometer for a complete TEMPEST mission using a closely-spaced train of eight 6U CubeSats with identical low-mass, low-power millimeter-wave sensors to sample rapid changes in convection and surrounding water vapor every 3-4 minutes for up to 30 minutes. The TEMPEST-D satellite was launched on May 21, 2018 from NASA Wallops to the ISS and was successfully deployed on July 13, 2018, into a 400-km orbit at 51.6° inclination. The TEMPEST-D sensor has been operating nearly continuously since its first light data on September 5, 2018. On-orbit results indicate that TEMPEST-D is a very well-calibrated, highly stable radiometer, indistinguishable in performance from larger operational sensors.