A scanning LIDAR system for active hazard detection and avoidance during landing on Europa

Active hazard detection and avoidance will be required for landing on Europa due to a lack of a priori knowledge of surface features similar in size to the lander. A light detection and ranging (lidar) instrument can provide both long distance (8 km) ranging and close-range (500 m) imaging to enable real-time hazard detection during landing operations. An example space-qualified lidar instrument is the Vision Navigation Sensor (VNS) on the Sensor Test for Orion Relative-navigation Risk Mitigation (STORRM) mission in 2011 on STS-134. The VNS consists of a single box housing a laser, transmit and receive optics, focal plane assembly, electronic assemblies, and mechanical components. The instrument operates in dual mode to change the field of illumination for near or far targets. On STS-134 the VNS successfully acquired range and intensity images as the Shuttle docked with ISS. The VNS was subsequently installed on ISS in February, 2017, as part of NASA's Raven technology demonstration and is operating with more integrated processing algorithms. Raven's flash lidar observes vehicles as they approach and depart ISS, performing calculations onboard to test autonomous rendezvous capability. We present potential modifications to the VNS system that could address the unique challenges posed by the Europa environment and landing operations, while reducing payload size, weight and power. We present these different systems within the context of the landing Concept of Operations as laid out in the Europa Lander Science Definition Team Report.