From Greenwich Mean to Eastern Standard, there’s more than 30 timezones in use today.
But one more may soon be added – and it would be literally out of this world.
The US government has told NASA that an official timezone needs to be created for the moon, because seconds tick slightly faster there than they do on Earth.
This timezone – provisionally called Coordinated Lunar Time (LTC) – would be used by astronauts living and working on the moon later this decade.
The idea has already been floated by the European Space Agency, but the Biden administration has ordered NASA to have ‘LTC’ officially set up by 2026.
Because the moon has a smaller mass than Earth, the gravitational pull on the moon is weaker.
As a result, time moves slightly faster on the moon than on Earth – around 58.7 microseconds faster per day, ‘with ‘additional periodic variations’, according to the US government in a memo.
Although this is less than the blink of an eye, tiny time differences between the Earth and the moon could cause communication problems during future moon missions.
‘Time passes at a very slightly different rate on the moon due to its different gravity,’ Sara Russell, professor of planetary sciences at the Natural History Museum, told MailOnline.
‘That difference doesn’t matter at all for earthlings, but is really important for coordinating complex electronic communications.
‘Working all this out is essential if we are to explore and ultimately live on the moon.’
As yet, it’s unclear how a lunar time system would work, or what a lunar clock would look like.
Dr Ruth Ogden, professor of the psychology of time at Liverpool John Moores University, said a simple tweaking of the types of clocks we have in our homes is ‘unlikely to be sufficient’, but called LTC a ‘great idea’.
‘We will probably need a moon timescale which moves outside of the traditional day and night understanding of time,’ she told MailOnline.
‘For astronauts on the moon, having a time zone which is centred around their experience or day and night on the moon may help them to acclimatise more quickly.’
On Earth, most clocks and time zones are based on Coordinated Universal Time (UCT), which relies on a vast global network of ultra-precise atomic clocks.
These atomic clocks measure changes in the state of atoms and generate an average that ultimately makes up a precise time.
But due to the gravitational differences, if these clocks were on the moon they would tick around 58.7 microseconds faster per day.
‘An atomic clock on the moon will tick at a different rate than a clock on Earth,’ said Kevin Coggins, deputy associate administrator at NASA.
‘It makes sense that when you go to another body, like the moon or Mars, that each one gets its own heartbeat.’
Nations venturing to the lunar surface have long used their own country’s timezones when performing missions.
For example, the Apollo missions of the 1960s and 1970s – when man stood on the moon for the first time – NASA used Central Time Zone (CDT) as the missions were launched in Houston, Texas.
But scientists have warned this method will not be sustainable as space agencies around the world plan on establishing moon habitats.
Compared with the Apollo visits, astronauts during the upcoming Artemis programme will be staying on the moon longer.
NASA’s Artemis programme kicked off in 2022 with the first mission, which sent an uncrewed Orion spacecraft around the moon and back.
The next mission, Artemis II which is due to take place in September 2025, will send four astronauts on a trip around the moon and back home.
Then, Artemis III, taking place September 2026, will actually land humans on the lunar surface – specifically the moon’s south polar region.
Eventually as part of its Artemis programme, NASA plans to have set up a base camp in the lunar south region by the end of this decade.
Dr. Thomas Hughes is a UK-based scientist and science communicator who makes complex topics accessible to readers. His articles explore breakthroughs in various scientific disciplines, from space exploration to cutting-edge research.