It sounds like a trick question you'd get at a bar trivia night. Someone leans over and asks, "Hey, what is earth's moon called?" and you're sitting there thinking, The Moon, obviously. But then you start second-guessing yourself. Is there a secret Latin name? Did I miss a meeting where they renamed it after a Greek goddess or some billionaire?
The truth is actually kinda boring, but also deeply fascinating in its own weird way.
Our moon is just called "the Moon." Capital M. No flair. No fancy branding. It's the only major celestial body in our solar system that doesn't have a distinct, formal name like Ganymede or Enceladus. We were so used to it being the only one around that for thousands of years, we didn't think we needed to be specific.
Why We Never Gave It a Proper Name
For most of human history, we were pretty provincial about space. We didn't know other planets had moons. To the ancient Greeks, Romans, and Babylonians, there was "the sun" and "the moon." That was the whole inventory.
When Galileo Galilei pointed his telescope at Jupiter in 1610 and saw four little dots orbiting it, the scientific world had a collective "oh crap" moment. Suddenly, our moon wasn't the moon; it was just a moon. But by then, the name had already stuck for a few thousand years. International Astronomical Union (IAU) rules now dictate that the English name for our natural satellite is "the Moon," capitalized to distinguish it from other generic moons.
The Latin Connection
You’ve probably heard people call it "Luna." Honestly, that sounds much cooler. It sounds like something out of a sci-fi novel. But "Luna" is simply the Latin word for moon. It's not a formal scientific name in the way that "Mars" is the name of the fourth planet. If you're speaking Italian or Spanish, you're calling it Luna because that’s just the word in your language.
In the world of professional astronomy, they stick to the English "Moon."
NASA and the IAU are pretty strict about this. While they allow for cultural variations, if you are writing a peer-reviewed paper on lunar basalt, you aren't writing about "Luna." You're writing about the Moon. It’s a bit of a linguistic trap. We use "lunar" as an adjective—lunar eclipse, lunar module, lunar orbit—but we never transitioned the noun to match.
🔗 Read more: When Was the iPhone 4 Launched: The Day the Smartphone Changed Forever
The Confusion with Other "Moons"
This naming convention creates a massive headache for writers and scientists. If I say, "Titan is a moon," I’m using the word as a category of object. A natural satellite. But if I say, "I'm looking at the Moon," I'm talking about a specific place with craters and footprints.
There are currently over 200 known moons in our solar system. Jupiter and Saturn are basically hoarding them.
- Jupiter has Io, Europa, and Callisto.
- Saturn has Titan and Mimas (the one that looks like the Death Star).
- Even tiny Pluto has Charon.
Every single one of those has a name rooted in mythology, mostly Greek or Roman. Our Moon? It just gets the job title. It's like having a dog and naming it "Dog." It works, but it lacks a certain personality.
What Other Cultures Call It
If you aren't using the Western-centric IAU naming convention, the answer to what is earth's moon called changes drastically.
In Mandarin, it’s Yuèqiú. In Hindi, it’s Chandra. To the ancient Egyptians, it was Iah. These aren't just names; they're tied to deities and complex calendars. The Moon has been the timekeeper for humanity since we were living in caves. It’s the reason we have "months." The word "month" actually shares a linguistic root with the word "moon."
We’ve basically built our entire concept of time around this nameless rock.
The Selene Misconception
Some people argue that "Selene" is the scientific name. Selene was the Greek goddess of the Moon, sister to Helios (the Sun). While we use "selenology" to describe the study of the Moon’s geology, Selene isn't the official name. It’s just another piece of the etymological puzzle.
Does It Actually Matter?
You might think this is all just semantics. And, well, it is. But as we get closer to establishing permanent bases on the lunar surface—thanks to programs like NASA’s Artemis—names are going to start mattering a lot more.
Imagine living in a colony on the Moon and someone asks where you're from. "The Moon" sounds a bit vague when there are dozens of other inhabited rocks in the solar system (in a hypothetical future, anyway).
Actually, the IAU has a "Working Group for Planetary System Nomenclature." These are the folks who decide what to call craters, mountains, and plains on other worlds. They’ve named thousands of features on our Moon, from the Sea of Tranquility (where Apollo 11 landed) to the Shackleton Crater at the south pole. Yet, the big rock itself remains "the Moon."
How to Talk About the Moon Like a Pro
If you want to sound like you know your stuff, keep these distinctions in mind:
📖 Related: The Real Story Behind Nobel Prize for Physics Winners and Why Their Discoveries Change Your Life
- Capitalization is key. If you're writing "the moon" with a lowercase 'm', you're talking about any natural satellite. If you use "the Moon," you're talking about Earth's specific companion.
- Avoid "Luna" in formal settings. It's a great name for a pet or a fictional spaceship, but in a scientific context, it's just the Latin translation.
- Use "Natural Satellite" for variety. If you're tired of saying "the Moon" over and over again, this is the technical term that clarifies exactly what the object is.
The Moon is a bit of an anomaly anyway. It's huge compared to our planet. Most moons are tiny specks relative to their host planets. Ours is so big that some astronomers argue Earth and the Moon are actually a "double planet" system.
Actionable Steps for Stargazers and Hobbyists
If you're fascinated by the Moon and want to go beyond just knowing what it's called, here is how you can actually engage with it:
- Get a Moon Map: Use a tool like the NASA Lunar Reconnaissance Orbiter (LRO) gallery online. You can zoom in on the exact spots where humans have walked. It makes the "nameless" rock feel much more like a real destination.
- Track the Phases: Download an app like My Moon Phase. Don't just look for the full moon; the "terminator line" (the line between light and dark) is where you see the most dramatic crater shadows through binoculars.
- Understand the "Lunar" Language: When you hear terms like perigee (when it's closest to Earth) or apogee (when it's furthest), you're seeing the physics that keeps our "nameless" satellite in the sky.
- Look for the "Old Moon in the New Moon's Arms": This is a phenomenon called Earthshine. It's when sunlight reflects off Earth, hits the dark side of the Moon, and bounces back to your eyes. It’s a reminder that the Earth and the Moon are constantly talking to each other through light.
Knowing what is earth's moon called is just the entry point. Whether we call it the Moon, Luna, or just that big bright thing in the sky, it remains the only other world humans have ever set foot on. That's worth more than a fancy name.
To keep exploring, check out the official IAU naming guidelines or dive into the mission logs of the Artemis program to see how we’re planning to return to those unnamed lunar plains.