Galileo goes to the Moon
Last year, history was made as a navigation receiver on the Moon determined its position in real time using signals from approximately 410 000 km away. The receiver, called the Lunar GNSS Receiver Experiment (LuGRE), acquired signals from four navigation satellites orbiting Earth: two Galileo satellites and two GPS satellites.
The mission also tested Galileo’s Emergency Warning Satellite Service (EWSS) on the Moon, demonstrating the robustness and reach of the planned service.
With an increasing number of lunar missions planned by space agencies and private companies in the coming decades, accurate lunar navigation will be a key component of sustainable lunar exploration and the development of a lunar economy.
LuGRE, the joint Italian Space Agency (ASI) and NASA mission, showed that existing terrestrial satellite navigation systems can be used for positioning, navigation and timing on the Moon. Transported to the Moon by Firefly’s Blue Ghost, LuGRE was the first navigation receiver to operate beyond low Earth orbit.
After arriving at the Moon on 2 March 2025, LuGRE maintained connections with Galileo and GPS satellites, in double frequency, for a lunar day (14 Earth days) before powering down. The success of LuGRE laid a foundation for future navigation systems on the Moon by demonstrating the feasibility of using navigation satellites orbiting Earth to determine positions on the Moon.
Emergency warning on the Moon
In early March 2025, Qascom, the company that developed LuGRE for ASI, proposed an additional joint demonstration to test the Galileo EWSS on the Moon during the LuGRE mission. This demonstration involved ESA, the European Commission (EC), the European Union Agency for the Space Programme (EUSPA) and the Centre National d’Etudes Spatiales SAR Galileo Data Service Provider (CNES/SGDSP).
With less than two weeks from proposal to execution, the partners swiftly coordinated their efforts to make the demonstration possible.
On 13 March 2025, a simulated emergency warning message alerting astronauts to seek shelter due to high radiation exposure was disseminated via select Galileo satellites and received by LuGRE’s receiver on the Moon as part of the data collected and downloaded to Earth.
LuGRE was the idea candidate for this off-world test because it was designed to receive navigation signals. The emergency warning message of the EWSS is sent via the same signal frequency as satellite navigation signals, so LuGRE was also able to pick up and process the EWSS test signal.
The success of this demonstration on the Moon showcases the robustness and reach of the Galileo EWSS, which will enter service later this year. It also highlights the collaboration between European institutional and industrial partners, a strong example of cross-agency collaboration enabling innovation in global navigation services.
Stepping towards lunar navigation
With lunar exploration expected to increase in the coming years, ESA’s Moonlight programme is developing navigation and telecommunications services for use on the Moon. By providing a unified lunar navigation and communication system, Moonlight will allow missions to focus on core activities, facilitating a long-term presence on the Moon and exploration of the Moon and beyond. Due to its compatibility with other planned lunar navigation systems, Moonlight will increase the future lunar service provision for many institutional and private users.
Newly approved at ESA’s Ministerial Council in 2025, NovaMoon will develop the first station on the Moon for high accuracy navigation. It will enhance the navigation services of Moonlight by providing an advanced geodetic and timing station on the Moon.
About Galileo
Galileo is currently the world’s most precise satellite navigation system, serving billions of smartphone users around the globe since entering Open Service in 2016. All smartphones sold in the European Single Market are now guaranteed Galileo-enabled. In addition, Galileo is making a difference across the fields of rail, maritime, agriculture, financial timing services and rescue operations.
The Galileo programme is managed and funded by the European Commission under the EU Space programme. Since its inception, ESA leads the design, development and qualification of the space and ground systems, as well as carrying out launches. The EU Agency for the Space Programme (EUSPA) acts as the service provider, bringing the satellites into service and overseeing their operation and the market and application needs.
For more info about Galileo: https://www.usegalileo.eu/EN/
About Moonlight
ESA is working with industrial and institutional partners on the Moonlight programme to establish reliable autonomous communication and navigation infrastructure for the Moon. This multi-directorate initiative, led by Connectivity and Secure Communications (CSC) with support from Navigation (NAV) and Human and Robotic Exploration (HRE), opens a path for the development of technologies to support the permanent presence and sustainable return to the Moon and beyond. Moonlight will benefit upcoming ESA, international and commercial lunar missions by lowering barriers, increasing mission scientific return and pushing the boundaries of human knowledge and exploration.
Learn more at https://www.esa.int/Applications/Connectivity_and_Secure_Communications/Moonlight