Attitude Corrections for Sounding Rocket Dropsondes Using Magnetometer and Langmuir Probe Measurements

In this work, we present a method for correcting attitude-dependent fluctuations in fixed-bias Langmuir probe ion density measurements from small, spin-stabilized sounding rocket dropsondes. The approach resolves dropsonde attitude using three-axis magnetometer data, observations from the Langmuir probe itself, and an analytical model of the sonde's rotational motion. Together, these inputs constrain the dropsonde's angular momentum vector in inertial space and enable reconstruction of its time-resolved attitude without requiring prior knowledge of the sonde's orientation at deployment. The derived attitude solution is then used to correct the Langmuir probe ion density measurements for orientation-dependent changes in collection geometry caused by the sonde's precessional motion. This technique is applied to data from the August 2022 Sporadic E Electrodynamics Demonstration (SpEED Demon) sounding rocket campaign, in which four dropsondes were ejected. Validation is performed by comparing attitude-corrected dropsonde ion density measurements to those of the main payload in a near-coincident measurement regime. The corrected data show strong agreement with the main payload observations, demonstrating that this technique can recover physically consistent ion density profiles from spin-stabilized dropsonde measurements.