Why the moon could have its own time zone and 4 more space stories

INTRO This week in outer space, SpaceX came out swinging. After a last minute problem forced them to scrub a launch on Monday, on Thursday, SpaceX launched four astronauts to the International Space Station, including the first space traveler from the Arab world. In a separate mission on Monday, SpaceX successfully deployed the first set of second-generation Starlink satellites into Earth's orbit, and then they did it again on Friday afternoon. But this week's main story is about time itself. With dozens of lunar missions on the horizon, a joint international effort is being formed to standardize how we measure time on the moon. While at first glance, establishing a special time zone for the moon may not seem like that big of a deal, it kind of is. Let me explain.

Since 1967, we've measured time on Earth on a global scale using what's called Coordinated Universal Time, or UTC, which is based on super-accurate atomic clocks. UTC stays the same no matter where you are on the planet. But because human beings typically like to wake up in the morning and go to bed at night, we assign local time zones plus or minus one hour roughly every 15 degrees east or west of the international dateline. There are some oddities with state and national borders, and daylight savings time throws a big wrench in the works every six months. But generally speaking, you can always figure out what time it is anywhere else on the planet relative to UTC. For example, I live in Brooklyn, which is UTC minus five hours. My grandma lives in Queensland, Australia, which is UTC plus 10 hours.

That's a 15-hour difference. So, if I want to call her for her birthday at 10am next Friday in Australia, I actually need to place that call at 7pm on Thursday night in New York. So what does any of that have to do with space travel? Well, the same principle that allows us to determine local time based on location also works in reverse. Meaning, if you know your precise local time, not just by hour, but by a tiny fraction of a second, you're well on your way to figuring out your location. And that is super important for making things like navigation and communication systems operate with any kind of reliability. But the rules for Earth kind of go out the window once we leave. Currently, the time on the moon is based on local time at mission control for any given spacecraft.

So, say there's a rover from Cape Canaveral. If it's 7am in Florida, it's 7am on the moon, no matter where the rover actually is. But say that rover cross paths with a lander from Wenchang, China. Even though they'd be right next to each other, it'd be 7am for the rover and 8pm for the lander. Right now, that's not really a big problem. There just isn't that much stuff on the moon for it to matter. However, as countries and private companies expand moon missions in the coming decades, the European Space Agency believes a common lunar reference time will become vital to maintaining order.

But there isn't really a clear solution of how to go about that. Atomic clocks, like we use to establish UTC on Earth, would run ever so slightly faster on the moon due to lower gravity, and a more traditional solar model presents another set of problems. The time between one lunar high moon and the next is about 708.7 hours, and that doesn't factor easily with 24-hour days on Earth. Luckily, at least for the foreseeable future, this isn't going to have a major impact on the vast majority of Earthlings, and there are literal rocket scientists working on the solution. But sometime soon, lunar standard time could be a thing. Well, that's it for this week.

See you next Saturday for more, this week in outer space.