Physics‐Based Approach to Thermospheric Density Estimation Using CubeSat GPS Data

Abstract In Low Earth Orbit (LEO), atmospheric drag is the largest contributor to trajectory prediction error. The current thermospheric density model used in operations, High Accuracy Satellite Drag Model (HASDM), applies corrections an empirical every 3 hr using observations of 75+ calibration satellites. This work aims improve global estimation by utilizing a physics‐based space environment and precise GPS‐based orbit estimates LEO CubeSats. data assimilation approach presented here drivers Thermosphere‐Ionosphere‐Electrodynamics General Circulation (TIE‐GCM) 1.5 CubeSat GPS information. this work, Spire Global are demonstrate method only 10 satellites; true strength its potential exploit already collected on large constellations (hundreds CubeSats). Precise Determination (POD) information from CubeSats over 12 days sense field when Kp historical show minor moderate geomagnetic storm succession. paper provides direct comparison estimated density, derived our new method, HASDM Swarm mission density. A propagation analysis also executed comparing POD orbits propagated versus analyses that within 35% during storm‐time conditions, yields improvement 26% NRLMSISE‐00 compared HASDM, while outperforming second peak.