Artistic rendering of LuGRE and the GNSS constellations. In reality, the Earth-based GNSS constellations take up less than 10 degrees in the sky, as seen from the Moon. Credit: NASA/Dave Ryan
Space Communications and Navigation, global navigation satellite system, spacecraft navigation, GNSS, SSV, TEMPO, PNT 

Lunar Navigation Demonstration Mission Passes Critical Milestones

By ​Danny Baird

November 18, 2021

A NASA technology demonstration mission has passed critical milestones on its journey to the Moon. The mission’s unique approach to lunar navigation could revolutionize the ways Artemis engineers consider the navigation systems of future missions.

The Artemis missions are reinvigorating NASA’s exploration of the Moon. Artemis astronauts and robotic missions will prospect for resources, make revolutionary discoveries, and prove technologies key to future deep space exploration.

In support of these ambitions, navigation engineers at Goddard Space Flight Center in Greenbelt, Maryland, are building a system that can employ the same navigation satellite signals used on Earth for navigation on the Moon. Developed in collaboration with the Italian Space Agency, the Lunar GNSS Receiver Experiment (LuGRE) will fly on a NASA Commercial Lunar Payload Services mission awarded to Firefly Aerospace of Cedar Park, Texas.

A Global Navigation Satellite System (GNSS) is one of several navigation satellite constellations operated by the U.S., the European Union, Russia, and China. Additional regional systems are operated by India and Japan. GPS, the constellation operated by the U.S. Space Force, is the one many Americans use to navigate with their smart phones.

On Earth, GNSS signals enable navigation and provide precise timing in critical applications like banking, financial transactions, power grids, cellular networks, telecommunications, and more. In space, spacecraft can use these signals to determine their location, velocity, and time, which is critical to mission operations. Over the past decade, NASA has been working to extend the distance from Earth at which spacecraft can take advantage of these signals to navigate with more precision, timeliness, and availability.

The LuGRE instrument will land on the Moon’s Mare Crisium basin in 2023. There, LuGRE is expected to obtain the first GNSS fix on the lunar surface. LuGRE will receive signals from both GPS and Galileo, the GNSS constellation operated by the European Union. The data gathered will be used to develop operational lunar GNSS systems for future missions to the Moon.

This fall, the LuGRE team passed a number of critical milestones. NASA signed a formal agreement to collaborate with the Italian Space Agency on the mission. The team also completed its Critical Design Review in mid-September, confirming that the system design meets all the mission’s requirements. NASA also received the first delivery of LuGRE hardware from receiver developer Qascom srl in early October, with the flight hardware delivery expected in early spring.

Ultimately, the technologies demonstrated by the LuGRE mission will offer astronauts and robotic missions supplemental navigation data that could enhance the accuracy of maneuvers and operations. This data will improve safety and enable more precise science as NASA explores the Moon.