CubeSat On-Orbit Temperature Comparison to Thermal-Balance-Tuned-Model Predictions

Confidence in spacecraft thermal models can be built by tuning their numerous parameters using the results of a thermal-balance test. In such a test, the flight article is placed in a thermal vacuum chamber configured to be as similar to the orbital environment as possible. High power-draw subsystems in the spacecraft are “pulsed” on for a few minutes so that the heat propagation through the system can be measured and conductive values in the model tuned. The thermal model can then be used to make more reliable predictions for the orbital temperatures. The ultimate validation of the model is a comparison of the predictions to the actual on-orbit measured temperatures. This paper describes the procedure, analysis, and results of all of the aforementioned as they apply to the first Miniature X-ray Solar Spectrometer 3U CubeSat. The first Miniature X-ray Solar Spectrometer was deployed from the International Space Station on 16 May 2016 and deorbited on 6 May 2017. Many of the tuned-model parameters are appl...