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Low cost and low size-weight-and-power magnetometers can provide greater accessibility for distributed simultaneous measurements in the ionosphere, either onboard sounding rockets or on CubeSats. 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 this suite is one high performance Billingsley magnetometer (TFM65VQS) and six commercial-off-the-shelf magnetometers manufactured by the PNI Corporation (RM3100). Of the six, two PNI magnetometers are situated on a deployable boom on the main payload that also carries the Billingsley magnetometer. The remaining four PNI magnetometers are distributed among four ejectable subpayloads. These low-cost and low SWaP magnetometers can achieve a resolution of approximately 1.5 nT and a precision of +/- 4 nT (one sigma) at 15 Hz in a uniform magnetic field. This performance is sufficient for detecting and measuring field aligned currents as well as a variety of other geomagnetic disturbances. The magnetometers are calibrated against an independently calibrated flux-gate magnetometer inside a Helmholtz cage. Zero field offsets are quantified inside a triple-layer mu-metal zero gauss chamber. This work will present the calibration process, the calibration results, and the flight performance of these sensors from the SpEED Demon sounding rocket launch.

Spacecraft in the near-Earth environment experience electrostatic charging from thermal plasma, surface contamination, photoelectron emission, and additional charge sources onboard. Unknown or incorrect values of space- craft floating potential can lead to erroneous scientific measurements. Sweeping Langmuir Probes (SLP) can provide spacecraft charging values but frequently experience surface contamination from dust, oils, water, and/or surface oxidation. This contamination presents itself through distortion of the collected Current Voltage (IV) curve and can lead to incorrect potential measurements. This relationship is investigated through simulation, using Simulation Program with Integrated Circuit Emphasis (SPICE) to simulate a contaminated SLP in Earth’s ionosphere. The resulting error in the SLP’s potential measurement is discussed and new methods for deriving the spacecraft floating potential are presented. The results are then verified using in-situ sounding rocket data.

Measurements of aerodynamic drag on objects can be used to determine the density of the medium provided other variables are known. The Space and Atmospheric Instrumentation Laboratory launched a midlatitude sounding rocket named SpEED Demon from Wallops Flight Facility in August 2022. Among the instruments onboard were sensitive low-cost MEMS accelerometers allowing for neutral density measurements through the drag technique 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. We present the flight performance and results of this drag-based density measurement technique from the SpEED Demon launch. Drag-derived density results are compared with density measurements from an ionization gauge instrument and the MSIS atmospheric model to provide validation of the technique, showing agreement within 10% in the 80-100km altitude range.