Can Astronauts Use GPS to Navigate on the Moon? NASA Scientists Say Yes
Scientists say lunar explorers could ‘see’ enough Earth-orbiting satellites to make an expensive new system unnecessary
By Ned Potter, March 17, 2020
If astronauts reach the moon as planned under NASA’s Project Artemis, they’ll have work to do. A major objective will be to mine deposits of ice in craters near the lunar south pole—useful not only for water but because it can be broken down into hydrogen and oxygen. But they’ll need guidance to navigate precisely to the spots where robotic spacecraft have pointed to the ice on the lunar map. They’ll also need to rendezvous with equipment sent on ahead of them such as landing ships, lunar rovers, drilling equipment, and supply vehicles. There can be no guessing. They will need to know exactly where they are in real time, whether they’re in lunar orbit or on the moon’s very alien surface.
Which got some scientists thinking. Here on Earth, our lives have been transformed by the Global Positioning System, fleets of satellites operated by the United States and other countries that are used in myriad ways to help people navigate. Down here, GPS is capable of pinpointing locations with accuracy measured in centimeters. Could it help astronauts on lunar voyages?
Kar-Ming Cheung and Charles Lee of NASA’s Jet Propulsion Laboratory in California did the math, and concluded that the answer is yes: Signals from existing global navigation satellites near the Earth could be used to guide astronauts in lunar orbit, 385,000 km away. The researchers presented their newest findings at the IEEE Aerospace Conference in Montana this month.
“We are trying to get it working, especially with the big flood of missions in the next few years,” said Cheung. “We have to have the infrastructure to do the positioning of those vehicles.”