Earthly satnav systems worked for Blue Ghost Moon lander
An experimental module attached to Firefly Aerospace’s Blue Ghost Moon lander successfully used Earth’s orbiting satnav systems, a feat that suggests a specialized lunar positioning system may not be needed.
The module is called the Lunar GNSS Receiver Experiment, aka LuGRE, which landed on the surface of the Moon Sunday aboard Blue Ghost, the first privately-built-and-operated spacecraft to successfully touch down on Earth’s natural satellite.
On Monday, LuGRE picked up signals from both America’s Global Positioning System (GPS) and the EU’s Galileo satnav constellations. The instrument then managed to acquire a navigational fix on the lunar surface using those signals, some 225,000 miles from Earth. That’s gotta involve some very cool mathematics to achieve that.
By doing so, it demonstrated that Terran satellite-navigation signals designed to aid earthly roaming can also work on Luna.
That’s good news because GPS and Galileo are two of several so-called global navigation satellite systems, or GNSS, orbiting our home planet. China, India, and Russia also operate such constellations, meaning there are plenty of satellites for future Moon missions to tap.
“LuGRE shows us that we can successfully acquire and track GNSS signals at the Moon,” enthused NASA Space Communications and Navigation program deputy associate administrator Kevin Coggins. “This is a very exciting discovery for lunar navigation, and we hope to leverage this capability for future missions.”
LuGRE also, we’re told, received signals from orbiting satnav systems and acquired its position while in transit to the Moon, and while circling it. One of its connections was made while 243,000 miles (391,000 km) from Earth, a new record for the most distant GPS fix that topped the 209,900-mile (336,000 km) hookup achieved by NASA’s Magnetospheric Multiscale Mission.
Dump the street directory
NASA engineers track spacecraft using sensors aboard the craft, Earth-based tracking stations, and other tools.
LuGRE’s successful in-transit GNSS positioning suggests future Lunar missions may use more automation.
“Using GNSS signals for navigation can reduce reliance on human operators because these signals can be picked up and used autonomously by the spacecraft, even as far away as the Moon,” NASA said.
NASA and other space agencies planning to expand human presence to the Moon in the coming decades have been tackling the problem of lunar navigation for some time. Previous experiments have proposed simple approaches such as navigating the Moon’s surface using AI trained to triangulate a position based on landmarks, and complex ideas such as creating a fleet of satellites dedicated to a lunar positioning system.
The other Blue Ghost payloads
Along with LuGRE, nine other NASA scientific payloads landed on the Moon aboard Blue Ghost, and several have already begun work.
An Electrodynamic Dust Shield has successfully used electrical forces to shake a little regolith dust that accumulated on the lander. The Lunar PlanetVac has begun to collect and transfer Moon dirt into sample return containers.
Other payloads will probe the Moon’s interior heat flow for clues about its formation and ways to capture natural resources for human habitation. The mission will also study Earth’s magnetosphere for clues about space weather, and an experimental Radiation Tolerant Computer continues to operate and (hopefully) prove its self-healing powers.
Blue Ghost’s mission plan calls for it to operate for 14 days, during which time LuGRE will continue to acquire GNSS signals to learn more about the long-term viability of its remote navigation method. ®
