International scientists seek to establish a unified lunar time scale

The 28th General Conference on Weights and Measures (CGPM) has adopted a resolution to establish an ‘international lunar time reference scale.’ This move addresses the technical challenges of coordinating future lunar exploration missions.

Due to Einstein’s theory of general relativity, time passes faster on the Moon than on Earth. A clock synchronized on Earth and placed in the Sea of Tranquility would drift by approximately 56 microseconds per day. While seemingly small, this discrepancy poses significant risks to the precision required for spacecraft landings, rover operations, and astronaut navigation. Experts note that lunar navigation requires temporal accuracy on the scale of a nanosecond.

Space agencies, including NASA, ESA, and agencies from China, India, and Japan, are planning to deploy satellite navigation systems around the Moon. To ensure operational safety and interoperability for all providers and users of lunar positioning, navigation, and timing services, the adoption of common regulations and a unified time standard is considered essential.