AURORA-HFSM: Autonomous Ultrasound & NIRS Rig for Orbital Redistribution Assessment – Headward Fluid Shift Monitor

Despite advances in space medicine, astronauts currently lack tools to comprehensively monitor their health in microgravity. This study aimed to demonstrate the potential of multimodal monitoring technologies to track physiological changes in space. The AURORA-HFSM experiment investigates headward fluid shifts and cerebrovascular dynamics during short-term weightlessness.

Healthy volunteers underwent multimodal monitoring during a parabolic flight campaign on the Airbus A310 Zero-G. Measurements integrated ultrasound (US), near-infrared spectroscopy (NIRS), indocyanine green (ICG) impedance tracking, and inertial measurement units (IMU) for motion synchronization. Signals were recorded continuously during each parabola (~22 s microgravity) across three gravity phases: 1.8 g pull-up (baseline), 0 g microgravity, and 1 g recovery. Each flight included 31 parabolas in three blocks, with short intermissions, providing ~11 minutes of cumulative 0 g exposure. This protocol enabled characterization of venous and arterial flow, tissue oxygenation, and thoracic fluid redistribution.

The study will provide the first synchronized multimodal dataset quantifying jugular, cerebral, and thoracic fluid dynamics during parabolic flight. Correlations between US, NIRS, and ICG indices will inform ESA research on intracranial fluid redistribution and guide the design of compact astronaut health-monitoring systems for long-duration missions.

AURORA demonstrates a feasible, safe, and operationally robust platform for multimodal physiological monitoring in microgravity. Medically certified components, low-voltage operation, mechanical robustness, and redundant data acquisition ensure ESA compliance and minimal residual risk. Expected outcomes include novel integrated biomarkers of cerebral hemodynamics, improved diagnostic accuracy, and enhanced monitoring for spaceflight and clinical applications, establishing AURORA as a translational platform bridging space physiology and astronaut health monitoring.