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SASSI2 (Student Aerothermal Spectrometer Satellite of Illinois and Indiana)


The Student Aerothermal Spectrometer Satellite of Illinois and Indiana (SASSI2) mission will characterize the flow and radiation generated by the diffuse bow shock formed during high-speed flight through the upper atmosphere.  Optical spectrographic measurements of the radiation will provide benchmark data for flow, radiation, and materials modeling, improving aerothermal reentry models.  Dr. Zach Putnam (UIUC) is the PI for SASSI2.  Alina Alexeenko is the PI for the Purdue science instruments.  David Spencer is Co-Investigator.

Concept of Operations

  1. SASSI2 will be launched as a secondary payload on an Orbital ATK resupply mission to the International Space Station.
  2. After being dropped off in a slightly elliptical Low Earth Orbit, the spacecraft will detumble using onboard magnetic torque rods, and face the sensors along the velocity vector.
  3. When the orbit dipps below 200 km, the spacecraft will begin taking pressure and heat flux data. When this altitude corresponds to a night pass, UV spectral readings will also be taken.
  4. As the CubeSat continues to de-orbit due to drag, increased measurement frequencies will be accompanied by an increased number of transmissions to the Globalstar network.
  5. Finally, the ionized air in front of the reentering CubeSat will prevent additional communications, and the spacecraft will burn up shortly after.

Payload Specs

  • Occupies less than ½  of the front face
  • Pressure ports are reconfigurable and can be placed anywhere on the ram face
  • Weight < 100 g
  • Power < 0.75 Watt
  • Can begin measuring data at 200 km and provide over 100 hours of data collection
  • Minimum pressure of 1 mPa
  • Max Heat flux of 98,000 W/m^2 (the Sun is 1,367 W/m^2)

University Partnerships


  • A. Pikus, A. Berger, M. Bolliger, D. Parkos, and A. Alexeenko, “DSMC Aerothermal Study for 3U CubeSat Probes in LEO,” in 47th AIAA Thermophysics Conference, AIAA AVIATION Forum, (AIAA 2017-4027), 2017.
  • M. Goggin, S. Tamrazian, R. Carlson, A. Tidwell, and D. Parkos, “CubeSat Sensor Platform for Reentry Aerothermodynamics,”  in Proceedings of the 31st Annual AIAA/USU Conference on Small Satellites, Small Space Science Missions, SSC17-IX-05, 2017.
  • M. Goggin, S. Tamrazian, R. Carlson, C. Vickers, and A. Alexeenko, “A Cubesat Sensor Platform for Atmospheric Entry Aerothermodynamics,” In 68th International Astronautical Congress,24th IAA Symposium on Small Satellite Missions (B4) Small Space Science Missions (2), 2017.