Mesosphere-Lower-Thermosphere Neutral Density Measurements from Low-cost COTS Accelerometers and Ionization Gauge

Measurements of aerodynamic drag on objects can be used to determine the density of the medium. The Space and Atmospheric Instrumentation Laboratory at Embry-Riddle Aeronautical University launched a midlatitude sounding rocket named SpEED Demon from Wallops Flight Facility in August 2022. SpEED Demon has a comprehensive suite of instruments for electrodynamics and neutral dynamics measurements. Among these are sensitive low-cost MEMS accelerometers allowing for neutral density measurements up to 100km in altitude. In addition to sensitive accelerometers on the main payload, four ejectable subpayloads also carry an accelerometer providing simultaneous multi-point neutral density measurements, akin to a ‘falling cylinder’ experiment. The measurements of neutral density via accelerometers will be cross-validated by an ionization gauge onboard the main payload. We present the flight performance and results of this measurement technique from the SpEED Demon launch.