Advancing Atmospheric Density Measurements in Suborbital Space Environments

The emergence of reusable launch vehicles has provided cost effective access to atmospheric regions that are historically difficult to reach directly with high-altitude balloons and orbiting satellites. AURORA (Atmospheric Upper Region Observation and Research Analysis) aims to leverage this paradigm shift to improve atmospheric density models and drag models, enhancing characterization of suborbital environments for reentry, descent, and landing of space vehicles. This paper presents a proof of concept for a low-cost mission to determine atmospheric density at discrete altitudes between 110 to 80 km. The AURORA mission consists of a payload including two subsystems: the deployment system and three sensor suites. The deployment subsystem secures three sensor suites during propulsion module boost and releases them at apogee via the JANUS integration platform provided by JHUAPL. Each sensor suite records position and velocity data using a high-precision GNSS (Global Navigation Satellite System) receiver, to derive atmospheric density using the drag acceleration equation. Following data collection, the suite releases a parachute to stabilize and slow down descent for uplink to the Iridium constellation before ground impact. AURORA utilizes the high data collection rate of 300 data points across 30 km to achieve a relative density error of less than 30%, the historical standard. AURORA’s design of three sensor suites enhances the robustness of density measurements, allowing outliers in data to be easily identified. The AURORA mission concept highlights the potential to advance in-situ measurement techniques for suborbital space regions, leveraging the cost-effective access to space provided by commercial space.