Plasma Density Irregularities Observed During Eclipse by the APEP Sounding Rocket Mission

Atmospheric Perturbations around Eclipse Path (APEP) is a sounding rocket campaign whose purpose is to study the electrodynamics of Earth’s ionosphere during the October 2023 annular eclipse and the April 2024 total eclipse in the United States. Each eclipse campaign consists of three launches: one prior to the peak local eclipse, one during the peak local eclipse, and one after the peak local eclipse. Each rocket is equipped with a suite of instruments to conduct in-situ measurements of the plasma environment and fully characterizes its associated electrodynamics. Each rocket deploys 4 ejectable subpayloads which are individually capable of performing in-situ plasma density and drag-based neutral density measurements. This work presents our findings concerning irregularities in plasma density as measured by Langmuir probes on each sounding rocket and each subpayload during the annular eclipse of 2023. Pending the success of the April 2024 launch, we will provide an analysis of such irregularities during two independent eclipse events and demonstrate the temporal evolution of the corresponding density profiles throughout the eclipse passage.