As humanity gears up for expanded lunar exploration under NASA's Artemis program, a groundbreaking study has revealed that time moves faster on the Moon than on Earth.
The discovery highlights the urgent need for a standardized lunar time system to ensure the success of future missions and the establishment of human bases on the Moon.
The study, published in The Astronomical Journal by researchers Bijunath Patla and Neil Ashby from the National Institute of Standards and Technology (NIST), calculated that clocks on the Moon tick 56 microseconds faster per day compared to those on Earth. This discrepancy is rooted in Einstein’s general theory of relativity and arises from two factors - the Moon's lower gravity causes clocks to run faster and the Moon’s motion relative to Earth slows them down.
Patla emphasized the importance of addressing this time drift, noting that even a seemingly minor variation could result in navigational errors of up to 17 kilometers per day, posing significant challenges for lunar operations.
Accurate timekeeping is crucial for mission safety and operational precision, as highlighted by Cheryl Gramling, a systems engineer at NASA’s Goddard Space Flight Center. She explained that lunar missions will require highly accurate positioning of rovers, landers, and astronauts—down to 10 meters. Timing errors at the nanosecond level could compromise these objectives.
The 56-microsecond drift was independently confirmed by Sergei Kopeikin from the University of Missouri and George Kaplan from the U.S. Naval Observatory. Their work also identified minor variations caused by tidal forces from the Sun and Jupiter, which must be factored into high-precision lunar operations.
In April 2024, the White House called for the development of a unified lunar time system, marking a critical step in preparations for increased international activity on the Moon. While such precision may not be immediately required, experts agree that laying the groundwork now will facilitate seamless coordination in the decades ahead.