A NASA test just proved GPS signals can be picked up on the moon

NASA and the Italian Space Agency say they have broken the record for the farthest detection of Earth-based navigation signals from 243,000 miles away in space. 

The test was among 10 experiments the U.S. space agency sent aboard the Blue Ghost moon lander, a private spacecraft built by Texas-based Firefly Aerospace. The uncrewed robotic lander softly touched down on the moon on March 2. A few hours after that landing, the receiver picked up and tracked signals again from the lunar surface — a first-time achievement. 

Called Lunar GNSS Receiver Experiment, or LuGRE, the demonstration has proven that a spacecraft on the moon or flying in lunar orbit could detect GPS and other navigation signals from Earth. This breakthrough could make future Artemis missions easier, allowing spaceships carrying astronauts to independently determine their location and speed as they approach the moon.

“This is a very exciting discovery for lunar navigation,” said Kevin Coggins, deputy associate administrator for NASA’s Space Communications and Navigation Program, in a statement, “and we hope to leverage this capability for future missions.”   

For the general public, it may seem odd that spacecraft continue to crash or keel over on the lunar surface, though the first soft moon landing occurred six decades ago. But landing on the moon remains onerous. The moon’s exosphere provides virtually no drag to slow a spacecraft down. And there’s the fact that everything is about six times tippier there than on Earth. Furthermore, there are no GPS systems on or around the moon to help guide a ship to its landing spot, which could be riddled with treacherous craters. 

Normally, engineers track spacecraft using signals from stations on Earth, along with sensors on the spacecraft themselves. The LuGRE experiment has shown that future landings might not require as much reliance on people in mission control if distant spacecraft can use Earth’s navigation signals autonomously.

These navigation signals refer to radio signals sent from satellites in Earth’s Global Navigation Satellite System, which includes GPS used in the United States and Galileo, a similar system used in Europe. The signals contain information about a satellite’s location and the exact time it was sent. Smartphones, cars, and airplanes receive these signals, and the directions they provide have become an indispensable part of everyday life.

The Earth-orbiting satellites don’t just send signals straight down to the ground but far into space. The question was just how far they could reach and still be helpful. The previous record holder for signal acquisition was 209,900 miles from Earth, a feat achieved by NASA’s Magnetospheric Multiscale Mission. 

Given that the signals are significantly weaker at a quarter-million miles from Earth — and come from satellites that weren’t designed for lunar navigation — they aren’t a permanent solution for the problem. In the future, a system of satellites orbiting the moon could provide stronger and more reliable navigation service. 

But for now, engineers are excited about the advancement and what it could mean for a potential lunar economy. Mining for lunar water alone could be a $206 billion industry over the next 30 years, according to Watts, Griffis, and McOuat, a geological and mining consulting firm. In order for the space between Earth and the moon to host such an industry, though, navigation improvements are critical. 

The LuGRE experiment was a team effort between NASA, its Italian counterpart, and some industry groups, including Qascom and Politecnico di Torino. The receiver was the first Italian-built hardware to operate on the moon, and the study won’t just benefit the United States and Italy, but anyone headed to the moon. The partners intend to make their data public.  

“A project like LuGRE isn’t about NASA alone,” said Lauren Konitzer, a NASA navigation and mission design engineer, in a statement. “We’re sharing our discoveries with the world.”