Diamond-based magnetometer aboard the International Space Station

Precise mapping of the geomagnetic field is essential for understanding Earth’s geodynamics, space weather interactions, and navigation applications. Traditional magnetometers face limitations in sensitivity for a wide dynamic range, and compactness. To address these challenges, the OSCAR-QUBE quantum magnetometer based on nitrogen-vacancy centers in diamond was developed, providing a sensitive and compact solution for space-based magnetic-field measurements. Our system employs optically detected magnetic resonance to measure magnetic fields utilizing the quantum properties of nitrogen-vacancy centers in a miniaturized design. The form factor of the final device was 1U ( 10 × 10 × 10 cm 3 ), weighing 420 g, and had a power consumption of 5 W. Deployed aboard the International Space Station, our magnetometer measured high-resolution magnetic-field maps, achieving a sensitivity of < 300 nT / Hz and successfully demonstrating vector magnetic-field mapping under low-Earth-orbit conditions. These results validate the flight-proven application of diamond quantum sensing in space, demonstrating the feasibility of solid-state quantum magnetometry for next-generation remote sensing and Earth observation missions. This work lays the foundation for future compact, multisensor quantum payloads for both scientific and commercial space applications.