In-Situ Neutral Measurements from the APEP Eclipse Rocket Campaign

The APEP (Atmospheric Perturbations around Eclipse Path) campaign was a series of three sounding rockets launched from White Sands Missile Range during the October 2023 annular eclipse. The rockets were launched in sequence: 35 minutes before peak local eclipse, during peak local eclipse, and 35 minutes after peak local eclipse. The payloads were comprehensively instrumented for electrodynamics and neutral dynamics measurements. For neutral dynamics, the main payload carried two ionization gauges for measurements throughout the flight and a sensitive accelerometer for drag-based measurements up to 110km. Additionally, four ejectable subpayloads carried accelerometers for distributed drag-based neutral density measurement. Currently, the same three rockets are also planned to be re-launched during the April 2024 total eclipse. This work will present the flight performance and initial observations of neutral dynamics during the APEP Annular Eclipse launches. We will also present results from the total eclipse, pending successful launches.