The LUMIO Radio Science Experiment

The European Space Agency mission LUMIO (Lunar Meteoroid Impacts Observer) aims to characterize the lunar and near-Earth meteoroid environment by imaging impact flashes on the far side of the Moon. During its 1-year operative phase along a quasi-periodic Halo orbit about the Earth-Moon Lagrangian point L2, LUMIO will observe the lunar far side while keeping its line of sight to the Earth unobstructed. With this geometry, the LUMIO spacecraft may be the first miniaturized satellite to exploit its radio communication system to carry out bistatic radar observations of the near-limb regions of the Moon, which may help characterize the surface roughness and dielectric constant around recent impact sites. Furthermore, high-frequency VIS-NIR images collected by the LUMIO-Cam during science operations represent an opportunity for testing innovative orbit determination techniques, such as using precise timing of stellar occultations to complement ground-based radiometric measurements. Stellar occultation measurements are expected to improve the navigation accuracy during science observation windows, aiding in absolute positioning of the impact sites and reducing the reliance on ground tracking. This work will outline the proposed LUMIO Radio Science Experiment, its main objectives, and expected performances, highlighting the potential of bistatic radar observations and stellar occultations to enhance the characterization of lunar impact flashes.