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“An atomic clock on the moon will tick at a different rate than a clock on Earth,” said Kevin Coggins, Nasa’s top communications and navigation official. “It makes sense that when you go to another body, like the moon or Mars, that each one gets its own heartbeat.”

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It’s possible that they don’t end up putting atomic clocks on the moon, but it’s on the table, they haven’t worked out the details yet.

The point of the lunar time zone is not to have a specific UTC offset like other timezones. The moon would have its own set of atomic clocks, and time could be coordinated with earth based on ratio instead of offset.