A Brief on Lunar Coordinated Time

Contributors: Philip Linden, Christopher Rabotin

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Implementing Lunar Coordinated Time (LTC) is more complicated than you think. Doing it right means involving all stakeholders―public, private, military, civilian, and commercial―and allowing it to be independent of UTC.

Key Points

1. LTC is not a time zone, it is a time scale. It will continuously diverge from Coordinated Universal Time (UTC), but they have a relationship that we can predict and use to convert between the time scales.

2. This is not the first time science has defined a time scale outside of Earth’s gravity well. Dynamic Barycentric Time (TDB) is defined at the barycentre of the solar system and progresses at a different rate than UTC which varies over time. LTC, too, will deviate from UTC at different rates over time.

3. Including all stakeholders is key to defining an equitable, useful, and lasting timing infrastructure in the cislunar space. Timing is a mission-critical resource for navigation. It’s not just the definition of the time scale―the time still needs to be distributed to Lunar actors.

Explore Related Projects:

• Lunar TImekeeping