Multispectral Imaging Sensors for Asteroids Relative Navigation

Current missions to asteroids largely rely on visible imaging to perform relative navigation with respect to the target surface. A consequence of observing the body in the visible band is the large influence of illumination conditions, which could be mitigated by an imaging system working in other spectral bands. This paper studies the possibility to exploit multispectral imaging sensors for improving spacecrafts relative navigation in proximity of asteroids. Realistic sensors models are considered and thermal images are synthetically generated exploiting physics-based models. An optical navigation algorithm for pose estimation is tested with visible and thermal images, proving the possible advantages of the multispectral strategy.