NASA and the European Space Agency (ESA) have begun collaborating on the approach for how missions from both agencies can utilize the lunar relay and navigation services that each agency is separately planning to provide at the Moon. The goal is to operate a cooperative lunar network to support a range of missions in an efficient and complementary manner. A preliminary draft outlining the initial ideas for a joint concept of operations is provided at the link below.
The joint concept of operations will be defined in greater detail in the future and its evolution will take into consideration the inputs of commercial vendors being engaged to provide services, as well as input from users. The concept provides a starting point for detailed technical planning and implementation and can serve as a template for incorporating additional new partners in cooperative lunar communications and navigation operations.
Draft Joint Concept of Operations for Lunar Relay and Navigation Services