How our brains create time: time differs on the Moon (Humans)

by David Turell , Sunday, December 01, 2024, 22:15 (2 days ago) @ David Turell

Ask Einstein:

https://www.livescience.com/space/the-moon/time-moves-faster-on-the-moon-new-study-of-e...

"What time is it on the Moon?

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"The real question being puzzled over isn't "What time is it?" but, rather, "How quickly does time pass?"

"What time a clock reads can be set by any timekeeper, but physics determines how quickly time passes. In the early years of the 20th century, Albert Einstein determined that two observers won't agree on how long an hour is if they aren't moving at the same speed in the same direction. That disagreement also holds between a person on Earth's surface and another in orbit or on the Moon.

"'If we are on the Moon, clocks are going to tick differently [than on Earth]," said theoretical physicist Bijunath Patla of the National Institute of Standards and Technology (NIST) in Boulder, Colo. He noted that the Moon's motion relative to ours makes clocks run slower than Earth standard, but its lower gravity leads to clocks running faster. "So these are two competing effects, and the net result of this is a 56-microseconds-per-day drift." (That's 0.000056 second.)

"Patla and his NIST physicist colleague Neil Ashby used Einstein's theory of general relativity to calculate this number, an improvement over previous analyses. They published their results in the Astronomical Journal.

"Though a 56-microsecond difference is small by human standards, it's significant when it comes to guiding multiple missions with pinpoint accuracy or communicating between Earth and the Moon.

"'The fundamental thing is safety of navigation in the context of a lunar ecosystem when you have lots more activity on the Moon than you have now," said Cheryl Gramling, a systems engineer at NASA's Goddard Space Flight Center. "When it comes to navigation, a drift of 56 microseconds over a day between a clock on the Moon and [a clock] on Earth is a big difference, so you have to accommodate that.'"

Comment: it won't affect daily life on the Moon but setting orbits to return home.