Greenwich moon time?
As NASA strides to return astronauts to the lunar surface for the first time since the early 1970s, astronomical experts say that the orbital rock needs its own localized time zone.
Why?
Simply because Earthly clocks won’t get the job done due to changes in gravity off-world.
A new paper from the National Institute of Standards and Technology (NIST) explains that even the most efficient terrestrial clocks, which stay in rhythm using atomic principles, would tick slightly quicker at a rate of 56 microseconds per day on the moon, where gravity is weaker.
That is a sizeable number when considering the scale of forthcoming manned Artemis moon missions that will increase “the number of assets on the lunar surface,” add the authors, now published in “The Astronomical Journal.
“Communication and navigation systems rely on a network of clocks that are synchronized to each other within a few tens of nanoseconds.”
Essentially, similar to how car clocks lose accurate time after a while, the same would happen to equipment on the moon’s surface.
The proposed alternative still under creation and recently backed by the International Astronomical Union is the development of Lunar Coordinate Time. It would function similarly to the principle of Earthly Coordinated Universal Time (UTC).
That 1960-originated concept — within a nanosecond of accuracy — keeps a singular, ultra-specific time by averaging atomic clock measurements globally. UTC is utilized by scientists and laboratories throughout the world.
Experts could tweak the UTC for space exploration purposes.
“It’s like having the entire moon synchronized to one ‘time zone’ adjusted for the moon’s gravity, rather than having clocks gradually drift out of sync with Earth’s time,” NIST physicist Bijunath Patla said.
It is currently unknown whether there would be just one or several time zones on the moon.
Lunar Coordinate Time would also play a role in navigating space and the moon, added NIST physicist Neil Ashby. Specifically, it would lay the work for a “system similar to GPS” but on the moon, he said.
Palta is confident that this approach could be utilized for frontiers beyond just our lunar surface, too.
“The proposed framework underpinning lunar coordinate time could eventually enable exploration beyond the moon and even beyond our solar system,” the expert said.
Specifically, Albert Einstein’s theory of relativity first addressed the concept that time can move slower under different gravitational conditions.
In this case, the changes happen in part due to the moon orbiting around the Earth and our planet’s revolution around the sun.
