NASA's New Laser Array Enhances GPS Precision and Earth Observation

A NASA-developed laser retroreflector array (LRA) became operational on March 9 aboard a U.S. Space Force Global Positioning System (GPS) satellite. This technology is designed to improve the precision of GPS data, thereby enhancing location and navigation services for users and refining the accuracy of data from other Earth-observing satellites.

"This development is anticipated to result in more accurate location and navigation information for users globally."

New Array Goes Live on GPS Satellite

The laser retroreflector array was launched on January 27 aboard GPS III SV-09, the ninth Block III satellite in the U.S. Space Force's Global Positioning System constellation. Its activation on March 9 establishes its full operational status, connecting the satellite more precisely to the global coordinate system. This development is anticipated to result in more accurate location and navigation information for users globally.

Precision Measurement Through Laser Ranging

LRAs are instruments composed of mirrors shaped like cube corners. These mirrors are engineered to reflect light beams directly back to their source, a principle central to laser ranging. Laser ranging is a technique utilized to measure precise distances by observing the time required for light pulses to travel from a ground station to the LRA's mirrors on the satellite and return. This method has been identified as an efficient and cost-effective approach for improving GPS products.

Boosting Earth Observation and Scientific Data

Beyond direct GPS user benefits, the enhanced precision from the LRA supports other Earth-observing satellites. These satellites utilize onboard GPS receivers to determine their exact positions in space. More accurate GPS orbit information consequently improves the reliability and precision of the scientific data collected by these Earth-observing missions. This improved data is considered vital for advancing planetary understanding and for issuing natural hazard warnings. Specific Earth-observing satellites, such as ICESat-2, SWOT, and GRACE-FO, also employ laser-ranging technology for their orbital positioning.

Collaborative Development and Global Tracking

The development of these LRAs was a collaborative effort between NASA’s Space Geodesy Project and the Naval Research Laboratory’s Naval Center for Space Technology. NASA’s Space Geodesy Project also manages a global network of Satellite Laser Ranging stations. This network continuously tracks various satellites, including the recently operational GPS III satellite, to ensure ongoing accuracy and performance monitoring.