Perhaps the greatest, mind-bending quirk of our universe is the inherent trouble with timekeeping: Seconds tick by ever so slightly faster atop a mountain than they do in the valleys of Earth.
For practical purposes, most people don’t have to worry about those differences.
But a renewed space race has the United States and its allies, as well as China, dashing to create permanent settlements on the moon, and that has brought the idiosyncrasies of time, once again, to the forefront.
On the lunar surface, a single Earth day would be roughly 56 microseconds shorter than on our home planet — a tiny number that can lead to significant inconsistencies over time.
NASA and its international partners are currently grappling with this conundrum.
Scientists aren’t just looking to create a new “time zone” on the moon, as some headlines have suggested, said Cheryl Gramling, the lunar position, navigation, and timing and standards lead at NASA’s Goddard Space Flight Center in Maryland. Rather, the space agency and its partners are looking to create an entirely new “time scale,” or system of measurement that accounts for that fact that seconds tick by faster on the moon, Gramling noted.
The agency’s goal is to work with international partners to set up a new method of tracking time, specifically for the moon, that space-faring nations agree to observe.
A recent memo from the White House also directed NASA to map out its plans for this new time scale by December 31, calling it “foundational” to renewed US efforts to explore the lunar surface. The memo also asks that NASA implement such a system by the end of 2026, the same year the space agency is aiming to return astronauts to the moon for the first time in five decades.
For the world’s timekeepers, the coming months could be crucial for figuring out how to accurately keep lunar time — and reach agreements on how, when and where to put clocks on the moon.