Polar Lunar Vision Explorer: An Extremely Low Lunar Orbit CubeSat Mission Concept

The Moon has become a focal point of the new round of deep-space exploration, yet its permanently shadowed regions (PSRs), represented by lava tubes and impact craters, remain inaccessible to humans. To shed light on the Moon's darkest corners, this paper proposes the PolAr lunar Vision ExploreR (PAVER) mission concept. PAVER is an all-electric propulsion-based CubeSat operating in an extremely low lunar orbit (eLLO), with a mean altitude of 15 km and an orbital inclination of 89.4°. At this low altitude, PAVER employs active illumination to perform aerial-survey-level remote-sensing imaging of PSRs. This paper first elaborates in detail on the overall platform, power and propulsion subsystem, and payload configuration, ensuring the feasibility of the CubeSat’s core scientific exploration mission and the integrity of the flight control support system. Subsequently, a two-stage low-thrust transfer orbit design is proposed to define the journey from a Distant Retrograde Orbit to the eLLO mission orbit. Then, a Linked Autonomous Interplanetary Satellite Orbit Navigation (LiAISON) based orbit determination method is introduced, with measurements obtained via inter-satellite links and processed using the extended Kalman filter (EKF), achieving positioning accuracy better than 10 m in eLLO. Finally, eLLO maintenance is achieved through closed-loop periodic tuning of the eccentricity vector. Simulations reveal that maintaining the 15 km eLLO can be achieved for a 120-day mission lifetime at the cost of a velocity increment of 142.850 m/s, during which the minimum altitude reaches 2.166 km, with no risk of lunar impact, thereby verifying the feasibility of our proposed eLLO maintenance strategy.