The European Space Agency is proposing a precise navigation system at the Moon, much like the sat-nav technology we have here on Earth. It would enable spacecraft and astronauts to know exactly where they are when moving around the lunar body and to land with precision. The initiative, known as Moonlight, would also incorporate a telecommunications function. A large flotilla of lunar missions will be launched this decade. Chief among them will be the US space agency-led successor to Apollo. Called Project Artemis, this will put crews on the Moon for the first time in more than 50 years. "We are entering a new phase - the systematic exploration of our 'eighth continent', the Moon," said David Parker, the director of human and robotic exploration at Esa. "The Moon is a repository of 4.5 billion years of Solar System history, but we've hardly begun to unlock its secrets. And so Moonlight is something that we see as really exciting, as a necessary infrastructure to support sustained exploration." Esa is asking two industrial consortia in Europe to define what an integrated sat-nav and telecoms system at the Moon would look like. It'll include a constellation of at least three, but probably more, positioning-and-relay satellites to give global coverage, and will likely include some surface beacons, too, to augment the accuracy of the navigation signals. "The target we have at the moment is that the constellation would be able to allow for an accuracy of 100m and probably better. We think we are able to get to 30m in the first instance," explained Paul Verhoef, the director of Esa's navigation department. Moonlight is just at the feasibility stage at the moment - what is known in industry-speak as a Phase A/B1 study. The consortia will put their thinking on the technologies required in reports to Esa, who will then produce a defined and costed proposal to go before Europe's research ministers when they gather for their triennial council meeting next year. One consortium will be led by the UK small satellite manufacturer, Surrey Satellite Technology Limited. SSTL assembled the navigation payloads on the European Union's Galileo sat-nav system.