With the renewed interest in the Moon, several countries are launching projects to explore the Moon (at both institutional and private level). As part of the Moonlight Programme, the European Space Agency (ESA) is developing Lunar Communication and Navigation Services (LCNS) with its industrial partners. The Moon orbits, specifically the Elliptical Lunar Frozen Orbits (ELFO), are quite different compared to the GNSS orbits. This work presents a novel orbit model for the LCNS that can support different ELFOs and other orbits. The performance of the new model is measured in terms of accuracy and the number of bits (required to broadcast the information) against other available models. Such a model could be used to broadcast the ephemeris of the LCNS satellites within the navigation message of the LunaNet Augmented Forward Signal (AFS).

With the renewed interest in the Moon, manifested by the growing number of planned missions for the past decade, space agencies are investing in reliable and dedicated lunar communication and navigation systems and services, such as the Moonlight programme of the European Space Agency (ESA), to provide support to all types of lunar users (i.e., surface users, landers and orbiters). In the context of lunar human and robotic exploration, one of the critical phases will be the landing of spacecraft on lunar soil. This type of operation is far from trivial, as shown by the recent crashes such as the one of the Luna25 lander from the Russian Space Agency. A reliable method to position a lander during its descent could be provided by a dedicated lunar navigation system. This paper will focus on what the achievable positioning accuracy is for a lander landing on the Moon’s South Pole using dedicated satellite-based navigation services such as Moonlight. It will be shown that using the LCNS constellation and the altimeter can achieve a sub 50 m accuracy with a 99% confidence interval.

With the renewed interest in lunar exploration, evidenced by the increasing number of planned missions over the past decade, space agencies are investing in dedicated lunar communication and navigation systems, such as the European Space Agency’s (ESA) Moonlight Lunar Communication and Navigation System (LCNS), to support various types of missions. Other space agencies, such as NASA and JAXA, are also foreseeing to deploy similar infrastructure, which will all be interoperable according to the LunaNet Specification. One of the critical phases in both human and robotic lunar exploration is the landing of spacecrafts on the Moon’s surface. This operation is complex and challenging, as demonstrated by recent crashes like the Luna25 lander from the Russian Space Agency or the Intuitive Machine private lander. Reliable positioning capabilities during descent are among the various services offered by dedicated lunar navigation systems and shall enable safe and reliable landing to a 90 metres 3-sigma landing accuracy from a target point, as defined by the Global Exploration Roadmap Critical Technology Needs. Faulty landings can be due to several causes. This paper examines the achievable positioning accuracy for a lander targeting the Moon’s South Pole using satellite-based navigation services like Moonlight and how the impact of faulty sensors (such as a faulty IMU) can be mitigated using Moonlight LCNS.