Socially, we’ve agreed on a universal time and a set of time zones across our planet’s surface. But, what if we weren’t on our planet?

Let’s chat about lunar timekeeping – it’s quite the ride!

So, we all live by time here on Earth, don’t we? Clocks, alarms, they’re all part of our lives. Even if we ditched all of our gadgets and went back to nature, we’d still follow the rhythms of Earth spinning on its axis and circling the Sun. Socially, we’ve agreed on a universal time and a set of time zones across our planet’s surface. But, what if we weren’t on our planet?

Think about the International Space Station, where 16 sunsets a day make things interesting (especially for Muslim astronauts during Ramadan). The time there is set to Universal Time (UT), identical to Greenwich Mean Time (GMT).

Now, should the Moon follow the same clock as Earth? It’s an open question. With Artemis III set to land humans back on the lunar surface, there’s still no consensus about what time zone we’ll use. Current robotic missions use the time zones of their country of origin.

Measuring time on the Moon by using the Sun, like we do here, might not quite cut it. Lunar days are a whopping 14.77 Earth days, so we’d need to do some tweaking. One idea floating around is Lunar Standard Time, which keeps our seconds, minutes, and hours but calls a day a ‘cycle’, and 30 cycles make up a lunar day.

So, what about the timekeeping of the Apollo astronauts on the Moon?

Well, here’s a fun fact – they didn’t use any time zone at all! No UTC, no Florida time (where they launched), and no Houston time (where Mission Control was). They followed Ground Elapsed Time (now called Mission Elapsed Time), counting minutes, hours, and days from the moment of launch.

This made sense for short missions like Apollo or the Space Shuttle where everything was timed based on the launch. But for long-term lunar stays, we might need to rethink things. The European Space Agency has already invited us all to ponder this conundrum. It may not be urgent for astronauts right now, but as we start to set up communication systems around the Moon, we’ll need to make a decision. Time, as they say, will tell!