Simultaneous Multi-Point Ion Density Measurements from a Sounding Rocket Platform

The Space and Atmospheric Instrumentation Laboratory at Embry-Riddle Aeronautical University has developed a highly sensitive Positive Ion Probe (PIP) instrument capable of conducting high-cadence (5KHz) distributed relative-ion density measurements from a sounding rocket platform. The PIP features a wide dynamic-range electrometer design which allows for extremely sensitive in-situ plasma measurements. The instrument was debuted on a mid-latitude sounding rocket mission, called SpEED Demon, which launched from NASA's Wallops Flight Facility in August 2022. SpEED Demon incorporated a comprehensive suite of instruments for electrodynamics and neutral dynamics measurements. Included in this collection of instruments were multiple PIP sensors. The PIP suite of instruments consisted of a single boom-deployed spherical sensor on the main rocket payload and a cylindrical sensor on each of four ejectable subpayloads which allowed for simultaneous spatially-distributed measurements of ion density. The interpretation of these measurements may provide an understanding of patchy, small-scale plasma density gradients, horizontally and vertically, through a myriad of ionospheric phenomena. This work presents the PIP instrument design, calibration, and preliminary flight results from the SpEED Demon launch.