White House tasks NASA to create a clock standard for time on the Moon
In a policy announcement yesterday, the White House has directed NASA to establish a coordinated lunar time standard (dubbed LTC) for time on the Moon, similar to Univeral or Greenwich time (UTC) now used on Earth.
A unified time standard—Coordinated Lunar Time (LTC)—will act as the established standard to enable cislunar operations and can be tied to Coordinated Universal Time (UTC), the primary time standard globally used to regulate clocks and time on Earth. This policy directs NASA to work with the Departments of Commerce, Defense, State, and Transportation to deliver a strategy for the implementation of LTC no later than December 31, 2026. NASA will also coordinate with other federal agencies as appropriate and international partners through existing international forums, including Artemis Accords partner nations.
As noted in the full policy statement [pdf]:
Due to general and special relativity, the length of a second defined on Earth will appear distorted to an observer under different gravitational conditions, or to an observer moving at a high relative velocity. For example, to an observer on the Moon, an Earth-based clock will appear to lose on
average 58.7 microseconds per Earth-day with additional periodic variations.
While this difference would be utterly unnoticed by people, the difference will become a problem for GPS systems and other very sensitive systems that depend on precise timing. The new policy will attempt to prevent such issues by getting ahead of the problem. It will also work to coordinate this new lunar universal time with other nations doing lunar exploration.
In a policy announcement yesterday, the White House has directed NASA to establish a coordinated lunar time standard (dubbed LTC) for time on the Moon, similar to Univeral or Greenwich time (UTC) now used on Earth.
A unified time standard—Coordinated Lunar Time (LTC)—will act as the established standard to enable cislunar operations and can be tied to Coordinated Universal Time (UTC), the primary time standard globally used to regulate clocks and time on Earth. This policy directs NASA to work with the Departments of Commerce, Defense, State, and Transportation to deliver a strategy for the implementation of LTC no later than December 31, 2026. NASA will also coordinate with other federal agencies as appropriate and international partners through existing international forums, including Artemis Accords partner nations.
As noted in the full policy statement [pdf]:
Due to general and special relativity, the length of a second defined on Earth will appear distorted to an observer under different gravitational conditions, or to an observer moving at a high relative velocity. For example, to an observer on the Moon, an Earth-based clock will appear to lose on
average 58.7 microseconds per Earth-day with additional periodic variations.
While this difference would be utterly unnoticed by people, the difference will become a problem for GPS systems and other very sensitive systems that depend on precise timing. The new policy will attempt to prevent such issues by getting ahead of the problem. It will also work to coordinate this new lunar universal time with other nations doing lunar exploration.