Cheryl Gramling says it's about time to put a clock on the moon. She should know. Gramling's in charge of lunar position, navigation, and timing and standards at NASA's Goddard Space Flight Center in Maryland.
Here's why: time passes more quickly in weaker gravitational fields. Since the moon's gravitational field is about 1/6th of Earth's, a clock on the moon would tick faster than one on Earth. In addition, the moon is constantly moving relative to Earth, which results in time dilation. The net result is that a clock on the moon will run ahead of a clock on Earth by about 56 microseconds per Earth day.
While 56 microseconds doesn't seem like much, it can make a big difference to GPS navigation systems, which rely on time measured in nanoseconds. (56 microseconds are 56,000 nanoseconds.) This disparity that can snowball into major inconsistencies over time. In the 1960s, meteorologist/mathematician Edward Lorenz discovered that weather systems exhibit sensitive dependence on initial conditions, famously termed the "butterfly effect," (the presumably negligent air turbulence caused by a butterfly flapping its wings in China, could lead to — or prevent — in a hurricane in Florida down the road). Unless the time discrepancy between the Earth and the Moon is accounted for with meticulous precision, things could go quickly awry for travel between the Earth and the moon or operations on a lunar colony.
So, what's the proposed solution? As reported by CNN, NASA and its international partners are working on establishing a standardized lunar time system. This isn't just about setting a simple time zone but creating a new time scale for the Moon. As NASA's Artemis program aims to return humans to the Moon and establish a sustainable presence, getting lunar time right is more urgent than ever. The White House has asked NASA to develop a new time scale system by the end of 2026. If NASA uses Earth time rather than lunar time to devise the solution, they'll gain an extra 0.05 seconds. In the grand scheme of space exploration, every fraction of a second counts.
Previously:
• Relax by orbiting the Moon in real time
• Watch this awesome time-lapse video of the total lunar eclipse
• It's time to get beyond low earth orbit
• NASA's abandoned lunar lander is causing moonquakes
