Building SPARCS, an ultraviolet science CubeSat for exoplanet habitability studies, technology advancements, and mission training

The Star-Planet Activity Research CubeSat (SPARCS) is a NASA-funded 6U-CubeSat mission designed to monitor ultraviolet (UV) radiation from low-mass stars. These stars’ relatively high-frequency and high-energy UV flares significantly affect the atmospheres of orbiting exoplanets, driving atmospheric loss and altering the conditions for habitability. SPARCS aims to capture time-resolved photometric data in the far-UV and near-UV simultaneously to better characterize the flares and detect the strongest and rarest among them. In addition, SPARCS is testing innovative technology, such as delta-doped detectors with near 100% internal quantum efficiency and detector-integrated metal-dielectric UV bandpass filters. This mission will increase the technology readiness level of these critical components, positioning them for inclusion in future flagship missions such as the Habitable Worlds Observatory. We outline SPARCS’ mission goals and provide an update as the spacecraft is completed and awaits its planned late-2025 launch to a sun-synchronous low-Earth orbit. We also highlight the critical role of small missions in providing training and leadership development opportunities for students and researchers, advancing technology for larger observatories, and share lessons learned from collaborations among academic, government, and industry partners.