Draft:Coordinated Lunar Time

Coordinated Lunar Time or LTC is the proposed time standard analog to Universal Time on Earth for the Moon. The proposed standard was recommended for creation on 2 April, 2024 when the White House directed NASA to establish a unified standard of time for the moon and later, other celestial bodies. The primary direction for the order came from the Office of Science and Technology Policy and describes a plan to implement the standard by the end of the year in 2026.

History
As part of a ongoing global Space Race, a need exists for a universal time-keeping benchmark for lunar spacecraft and satellites that require precision for their upcoming missions. Due to differences in gravitational force and other factors, how time unfolds on the Moon relative to how it is perceived on Earth differs.

Under the Artemis program, and supported by the Commercial Lunar Payload Services missions, astronauts and a proposed scientific Moonbase are envisioned to take place on and around the lunar surface in the 2020s and onwards. The proposed standard would solve a current timekeeping issue. According to OSTP Chief Arati Prabhakar, currently, time would "appear to lose on average 58.7 microseconds per Earth-day and come with other periodic variations that would further drift moon time from Earth time".

The development of the standard will be a collaborative effort, initially by members of the Artemis Accords, but will be meant to apply globally. The initial proposal of the standard calls for four key features: traceability back to Coordinated Universal Time, accuracy sufficient for navigation and science, resilience to disruptions, and scalability to potential environments beyond cislunar space. LunaNet, an upcoming lunar communications and navigation service under development with the European Space Agency, calls for a Lunar Time System Standard which the LTC is meant to address.