The Moon

Earth’s only natural satellite — a rocky, dusty, magnificent world that has been our companion for 4.5 billion years. Here is the complete guide to the Moon, written for curious minds aged 7 to 12.

For teachers: free lesson plans, slide decks & worksheets →

Tonight, when you look up at the Moon, you’re seeing the same Moon that Neil Armstrong walked on in 1969 — and his footprints are still there. The Moon is Earth’s only natural satellite: a big rocky neighbour, about a quarter as wide as Earth, that has been travelling around our planet for four and a half billion years.

In this guide you’ll find out what the Moon is made of, how it formed, why it changes shape, and what humans are doing on the Moon right now. And there’s a lot going on right now — for the first time in over 50 years, astronauts have begun flying around the Moon again. In April 2026, four astronauts on Artemis II circled the Moon and came home safely. NASA is now preparing the missions that will land humans back on the surface.

Quick Moon Facts

• Diameter3,474 km (about ¼ of Earth’s width)
• Distance from Earth~384,400 km on average
• Age~4.5 billion years
• Day length29.5 Earth days from sunrise to sunrise
• GravityAbout 1/6 of Earth’s
• Surface temperature−173 °C at night to +127 °C in the day
• AtmosphereAlmost none — just a very thin exosphere
• Humans who have walked on it12 (so far)

What Is the Moon?

The Moon is Earth’s only natural satellite — a big rocky ball that travels around our planet. It is about a quarter as wide as Earth, sits roughly 384,400 km away, and is the brightest object in our night sky after the Sun.

The Moon does not make its own light. It glows because sunlight bounces off its dusty grey surface, like sunlight reflecting off a giant mirror in space. Whenever you see the Moon shining, you’re really seeing sunlight that has bounced off the Moon and travelled all the way back to your eyes.

For a deeper kid-friendly definition, see our simple explanation of the Moon.

Is the Moon a planet or a star?

No — the Moon is not a planet, and it isn’t a star either. A planet orbits the Sun directly, but the Moon orbits Earth. And stars (like the Sun) make their own light from giant nuclear reactions inside them, while the Moon only reflects sunlight. The Moon belongs to a different family: it’s a natural satellite, and Earth has exactly one.

Why the Moon Changes Shape — The 8 Phases of the Moon

Here’s the wild part: the Moon never actually changes shape. It’s always a ball. As the Moon travels around Earth once every 29.5 days, sunlight lights up half of it from a different angle each night — so we see a different amount of that lit-up half. That changing view is what we call the Moon’s phases.

Look up at the Moon two nights in a row. You’ll notice it’s just a little bit different. Over four weeks, that tiny difference adds up to a complete cycle of eight phases.

For everything about the cycle, jump to our complete guide to the 8 phases of the Moon.

The 8 Moon Phases — Named in Order

The eight phases of the Moon, in the order they happen, are:

1. New Moon — the lit side faces away from us; the Moon is almost invisible.
2. Waxing Crescent — a thin sliver of light starts to appear.
3. First Quarter — half of the visible side is lit (looks like a “D”).
4. Waxing Gibbous — more than half lit, getting close to full.
5. Full Moon — the whole visible side is lit; the brightest night of the cycle.
6. Waning Gibbous — past full, slowly shrinking.
7. Last Quarter — half lit again, but the other half (looks like a backwards “D”).
8. Waning Crescent — a thin sliver, shrinking back to nothing.

Then it all starts again. “Waxing” means growing; “waning” means shrinking. “Gibbous” rhymes with “ribbons” — it just means humped or bulging.

Why does the Moon change shape? (Hint: it is NOT Earth’s shadow!)

The Moon’s phases are not caused by Earth’s shadow falling on the Moon. That’s a totally different event called a lunar eclipse, and it only happens 2 to 4 times a year. What’s really happening is much simpler: the Sun always lights up half of the Moon, and as the Moon orbits Earth, our view of that lit half changes. Sometimes we see all of it (Full Moon). Sometimes we see just a sliver (crescent). Sometimes the lit half faces away from us completely (New Moon). For the full bust of this misconception, see why the Moon changes shape.

How Was the Moon Made? The Giant Impact Story

About 4.5 billion years ago, when Earth was very young, a Mars-sized planet that scientists call Theia smashed into the early Earth. The crash was so huge it sprayed a giant ring of red-hot rocky debris into space. Over millions of years, gravity slowly pulled that debris together into a ball — the Moon.

We can’t see Theia today, because Theia was destroyed in the collision. Most of its pieces became part of the Moon, and some sank into Earth.

How do scientists know? When Apollo astronauts brought back Moon rocks in the 1960s and 70s, those rocks turned out to look an awful lot like the rocks deep inside Earth. That’s exactly what the Giant Impact Hypothesis predicts.

Without Theia, the Moon — and probably us — wouldn’t be here.

Without Theia, the Moon probably wouldn’t exist — and Earth’s climate might not be stable enough for life to have evolved the way it did. Go deeper at our spoke on the Giant Impact Story.

What Does the Moon Look Like Up Close?

Up close, the Moon is a rocky, dusty, grey world covered in craters, vast dark plains called mare, and bright mountainous areas called highlands. The whole surface is buried under a powdery layer of crushed-up rock called regolith — the famous Moon dust that stuck to every Apollo astronaut’s spacesuit.

Stand on the Moon and you’d see no rivers, no oceans, no plants, no clouds — and the sky would always be black, even in the daytime, because there’s no air to scatter sunlight blue. See the full surface tour on our Moon’s surface spoke and a closer look at craters on the Moon.

Why does the Moon have so many craters?

The Moon has so many craters because, unlike Earth, it has almost no air, no wind, and no rain. When asteroids and comets crash into the Moon, the craters they leave behind never wear away. Earth gets hit just as often — but our weather, water and moving rocks erase Earth’s craters over millions of years. Imagine drawing a circle in sand on a windy beach. It vanishes in minutes. Now imagine drawing the same circle on bare concrete — it stays for years. That’s the difference between Earth’s surface and the Moon’s.

Are there moonquakes?

Yes! The Moon really does have its own version of earthquakes — called moonquakes. Apollo astronauts left special instruments on the Moon’s surface that have recorded thousands of them. Most are small. Some happen because Earth’s gravity squeezes the Moon a little. Others happen when meteors slam into the surface. Read more about moonquakes for kids.

Why Do We Always See the Same Side of the Moon?

Here’s something strange: no matter when you look at the Moon, you’re always seeing the same side. We never see the far side from Earth. Why?

The Moon does spin — but it spins at exactly the same speed as it orbits Earth. One spin and one orbit both take about 27 days. So one side always faces us, like a friend who keeps eye contact while you spin in a circle together. Scientists call this tidal locking.

But here’s an important myth-buster: there is no permanent “dark side” of the Moon. Pink Floyd was poetic, not scientific. Every part of the Moon gets two weeks of sunlight followed by two weeks of nighttime. The far side is just the side hidden from us — and we didn’t even see it until 1959, when a Soviet spacecraft called Luna 3 took the first photos.

Explore the full story at the far side of the Moon.

How the Moon Affects Earth

The Moon may be far away, but it does some surprisingly powerful things to Earth. It pulls our oceans into tides. It steadies the way Earth tilts on its axis (which keeps our seasons regular). It even lights up the sky for animals that hunt and travel at night.

How does the Moon cause tides?

The Moon’s gravity reaches all the way to Earth and pulls on our oceans. Water on the side facing the Moon is pulled up into a bulge — that side gets a high tide. The water on the opposite side also bulges out, because Earth itself is pulled slightly away from it. As Earth spins through both bulges every 24 hours, every coast gets two high tides and two low tides each day.

For the full pull-of-the-sea story, see how the Moon causes tides.

Is the Moon moving away from Earth?

Yes — the Moon is slowly drifting away from Earth, by about 3.8 cm every year. That’s roughly the speed your fingernails grow. The pull of Earth’s tides drags energy out of the Moon’s orbit and pushes the Moon gently outwards. Earth’s day is also getting slightly longer, by about 2 milliseconds every century, for the same reason.

Will the Moon ever crash into Earth?

No — the Moon will never crash into Earth. In fact it’s moving away, not closer. Earth and the Moon will be together for billions of years to come, with the Moon just slightly further away each year. You can sleep easy.

Eclipses Explained — Lunar and Solar

An eclipse is what happens when the Sun, Earth and Moon line up perfectly. There are two kinds, and they’re easy to mix up. A lunar eclipse is when Earth gets between the Sun and the Moon, so Earth’s shadow falls on the Moon. A solar eclipse is when the Moon gets between Earth and the Sun, so the Moon’s shadow falls on Earth.

For the full story, see our spokes on the lunar eclipse for kids and the solar eclipse for kids.

Why does the Moon turn red during a lunar eclipse?

During a total lunar eclipse the Moon doesn’t go completely dark — it turns a deep coppery red. People call this a Blood Moon. Sunlight bends through Earth’s atmosphere on the way to the Moon, and Earth’s air filters out the blue light. Only the red light makes it through to light the Moon up faintly. It’s the same reason sunsets look red. Watching a lunar eclipse is like seeing all of Earth’s sunsets at once — reflected back at you from the Moon.

How is a solar eclipse different from a lunar eclipse?

A solar eclipse happens at New Moon (when the Moon is between the Sun and Earth). A lunar eclipse happens at Full Moon (when Earth is between the Sun and the Moon). During a total solar eclipse the sky goes dark for a few minutes in the middle of the day, the stars come out, and the Sun’s glowing corona becomes visible around the edge of the Moon. It is one of nature’s most amazing sights.

When Humans First Walked on the Moon — The Apollo Story

In July 1969, millions of people around the world watched their televisions in amazement as the first humans stepped onto another world. The mission was called Apollo 11. The three astronauts were Neil Armstrong, Buzz Aldrin and Michael Collins.

They left Earth on 16 July 1969, riding a colossal Saturn V rocket — the most powerful rocket ever flown at the time. Four days later, on 20 July 1969, Armstrong and Aldrin landed their tiny lunar module — called Eagle — on a flat dark plain called the Sea of Tranquillity. Michael Collins stayed in orbit above them. When Armstrong stepped out, he said the words people still quote today: “That’s one small step for [a] man, one giant leap for mankind.”

The astronauts spent just over two hours bouncing around in the Moon’s low gravity, planting a flag, taking photographs and collecting Moon rocks. Then they climbed back into Eagle, blasted off, met up with Collins, and came home — safely splashing down in the Pacific Ocean on 24 July 1969. Read the full story at our Apollo 11 for kids spoke and browse every mission in our Apollo missions timeline.

Who was the first person on the Moon?

Neil Armstrong was the first person to walk on the Moon, on 20 July 1969. Buzz Aldrin was second, about 20 minutes later. Michael Collins, the third member of Apollo 11, orbited above them in the command module and never landed.

How many people have walked on the Moon?

Twelve people have walked on the Moon — all of them American astronauts, all between 1969 and 1972. The first was Neil Armstrong (Apollo 11); the last was Eugene Cernan (Apollo 17). No one has walked on the Moon since December 1972 — but that long pause is finally beginning to end.

Going Back to the Moon — The Artemis Programme

Apollo took humans to the Moon in the 1960s and 70s. Artemis is the new NASA programme — named after Apollo’s twin sister in Greek mythology — designed to bring people back. And it has already started.

Artemis I flew an uncrewed test mission around the Moon in November 2022. Artemis II lifted off from Florida on 1 April 2026 and splashed safely down in the Pacific Ocean ten days later, on 10 April 2026. The four-person crew became the first humans to leave Earth orbit since Apollo 17 in 1972.

Meet them: Reid Wiseman (commander), Victor Glover (pilot), Christina Koch (mission specialist) and Jeremy Hansen (mission specialist, Canadian Space Agency). Christina Koch became the first woman ever to fly to the Moon. Victor Glover became the first person of colour. Jeremy Hansen became the first non-American.

First woman. First person of colour. First non-American. First humans to leave Earth’s orbit in over 50 years.

So what’s next? Here’s the surprise — Artemis III will not be a Moon landing. NASA changed the plan in February 2026. The 2027 Artemis III mission will stay in low Earth orbit, where the four astronauts will practise docking the Orion spacecraft with the giant new commercial lunar landers being built by SpaceX (Starship) and Blue Origin (Blue Moon). It’s a vital safety rehearsal before the real landing.

The first crewed Moon landing of the Artemis era is now planned for Artemis IV in 2028. If everything goes well, four astronauts will become the first humans to walk on the Moon since 1972 — and the first ever to land near the lunar south pole, where the water ice is hiding.

Read more at our spoke on the Artemis programme.

Could humans live on the Moon one day?

Maybe — but it would be hard. The Moon has no air, big temperature swings, dangerous radiation, and dust that gets everywhere. Future Moon bases would probably be built underground or inside lava tubes (giant natural caves left by ancient volcanoes) to protect astronauts. The lunar south pole is the most likely spot for a first base, because of the water ice. Artemis IV will be the very first step. For more, see could humans live on the Moon.

Water on the Moon — A Game-Changing Discovery

For most of human history, scientists thought the Moon was bone dry. They were wrong.

There is water ice on the Moon — frozen solid, hiding in the bottoms of very deep craters near the lunar south pole that never see sunlight. These craters are called Permanently Shadowed Regions (PSRs), and the ice inside them has been frozen there for billions of years. The biggest known deposits are around Shackleton crater.

In August 2023, India’s Chandrayaan-3 mission landed near the south pole — the first spacecraft ever to land there. Its little Vikram lander and Pragyan rover beamed back evidence of all sorts of fascinating minerals near the ice.

Why does this matter? If astronauts can reach the ice, they can drink it, grow plants with it, or split it into hydrogen and oxygen — for breathing air, and even for rocket fuel for the trip home. Suddenly a long stay on the Moon looks much more possible. Dive into the full story at water on the Moon.

Moon vs Earth — How Do They Compare?

The Moon and Earth are next-door neighbours in space — but they’re really different worlds. Here’s how they stack up:

Feature	Earth	The Moon
Diameter	12,742 km	3,474 km (~¼ of Earth’s)
Gravity	9.8 m/s²	1.62 m/s² (~⅙ of Earth’s)
Day length	24 hours	29.5 Earth days
Atmosphere	Thick, breathable	Almost none (exosphere)
Surface	Rock, water, life	Rock, dust, craters
Temperature range	−90 °C to +60 °C	−173 °C to +127 °C
Number of moons	1 (the Moon!)	0

If you weigh 30 kg on Earth, you’d feel like only 5 kg on the Moon — light enough to jump six times higher. Try our Moon vs Earth side-by-side comparison and see how Moon vs Mars measures up too.

Why Full Moons Have So Many Names

People have given names to the Full Moons of every month for thousands of years. Many of the popular names you see today — Wolf Moon, Snow Moon, Worm Moon, Pink Moon, Flower Moon, Strawberry Moon, Buck Moon, Sturgeon Moon, Harvest Moon, Hunter’s Moon, Beaver Moon, Cold Moon — come from Algonquian-speaking Indigenous peoples of the northeastern United States and Canada (including the Anishinaabe / Ojibwe), plus English and Colonial American folk tradition. The list most people recognise today was standardised in print by The Old Farmer’s Almanac in the 1930s.

Then there are modern nicknames. A Supermoon is a Full Moon at the closest point in its orbit (it looks slightly bigger and brighter). A Blue Moon is the second Full Moon in one calendar month. A Blood Moon is what we call the deep red Moon of a total lunar eclipse.

See the full year of named Full Moons at Wolf Moon, Harvest Moon, Blue Moon and the bigger Full Moon story at our Full Moon spoke.

The Moon in Stories Around the World

The Moon is the same Moon, no matter where on Earth you stand. So nearly every human culture has told stories about it. In ancient Greece, Selene drove a silver chariot pulled by white horses across the night sky. In China, Chang’e is the Moon goddess who flew up to live on the Moon with a Jade Rabbit. In India, Chandra rides a silver chariot pulled by ten white horses. Across China, Korea, Japan and Vietnam, the dark patches on the Moon look like a rabbit pounding rice cakes — the same shape Indian and Aztec traditions also saw. Three continents that never met each other independently saw the same rabbit.

Read every story at Moon myths from around the world.

How We Came to Know the Moon — From Galileo to Today

For most of history, humans thought the Moon was a smooth, perfect ball — almost magical. Then, in 1609, an Italian scientist called Galileo Galilei pointed a brand-new invention — the telescope — up at the night sky. What he saw changed everything.

The Moon wasn’t smooth at all. It had mountains. Valleys. Craters. Galileo drew the first detailed pictures of the Moon ever made through a telescope, and proved that other worlds had landscapes, just like Earth. Three and a half centuries later, in 1959, the Soviet Luna 3 spacecraft sent back the first photograph of the Moon’s far side. Then humans landed there with Apollo.

Read the discovery story at Galileo and the Moon.

How to Watch the Moon Yourself

Here’s the best thing about the Moon — unlike black holes or distant planets, you can step outside and see it for yourself. Right now. Tonight.

With just your eyes, you can spot the Moon’s current phase, the big dark patches (mare), the bright “ray” patterns around the youngest craters, and the Moon during the daytime too — yes, really. With binoculars (you don’t need a telescope!), you can see five famous craters from your back garden: Tycho, Copernicus, Aristarchus, Plato and Kepler.

For more sky-watching tips, see how to watch the Moon.

Newest Moon Missions and Discoveries (2024–2026)

The Moon is in the news more than it has been in decades. Here’s what’s been happening:

• August 2023 — Chandrayaan-3 (India / ISRO) — first ever soft landing near the lunar south pole. Vikram and Pragyan studied minerals close to the water ice.
• January 2024 — SLIM (Japan / JAXA) — first Japanese Moon lander; touched down with super-precise accuracy.
• February 2024 — Intuitive Machines IM-1 (USA) — the first American lander on the Moon since Apollo 17 in 1972.
• June 2024 — Chang’e 6 (China / CNSA) — first ever mission to bring rocks back from the far side of the Moon.
• March 2025 — Blue Ghost (Firefly Aerospace, USA) — successful soft landing carrying NASA science instruments.
• April 2026 — Artemis II (NASA) — already happened! Four astronauts flew around the Moon and home — the first crewed lunar mission since 1972.
• Late 2027 — Artemis III (NASA, planned) — Earth-orbit docking rehearsal with commercial lunar landers (SpaceX Starship and Blue Origin Blue Moon).
• 2028 — Artemis IV (NASA, planned) — the planned return of humans to the Moon’s surface, targeting the lunar south pole.

After half a century of quiet, the Moon is once again the most exciting place in the Solar System.

10 More Fun Facts About the Moon for Kids

1. The Moon smells like burnt fireworks — Apollo astronauts said so when they took their helmets off inside the lander.
2. The Moon is slowly drifting away from Earth — about 3.8 cm per year, as fast as your fingernails grow.
3. The footprints Apollo astronauts left on the Moon could last for millions of years — there’s no wind or rain to wipe them away.
4. The Moon is bigger than Pluto.
5. You’d weigh about one-sixth of what you do on Earth.
6. A day on the Moon (sunrise to sunrise) lasts 29.5 Earth days.
7. The Moon has moonquakes — tiny earthquakes Apollo astronauts measured with seismometers.
8. The American flag from Apollo 11 fell over during liftoff — but the flags from Apollo 12 onwards are probably still standing.
9. Light from the Moon takes just 1.3 seconds to reach your eyes.
10. The Moon causes our tides — without it, the seas would behave very differently.

The Same Moon, Tonight

Tonight, when the Moon rises over your house, you’ll be looking at the same Moon that ancient cultures told stories about by firelight, that twelve astronauts walked on, and that the Artemis IV crew is already training to visit. The Moon isn’t just a bright object in the sky — it’s Earth’s closest neighbour, our oldest companion, and our oldest mystery.

One day, perhaps in your lifetime, people may live and work there.

Step outside tonight. Look up. You’re not just seeing a light in the sky — you’re seeing another world.

Frequently Asked Questions About the Moon

Moon Glossary — Tricky Words Explained

• Regolith (REG-oh-lith) — the powdery dust and crushed rock covering the Moon’s surface.
• Mare (MAH-ray, plural MAH-ree-uh) — the dark “seas” on the Moon, made of ancient hardened lava.
• Highlands — the bright mountainous areas on the Moon.
• Exosphere — the Moon’s extremely thin atmosphere (almost a vacuum).
• Perigee / Apogee — the closest / furthest points in the Moon’s orbit around Earth.
• Umbra / Penumbra — the inner / outer parts of an eclipse shadow.
• Totality — the moments during a total eclipse when the Sun or Moon is fully covered.
• Tidal locking — when a moon spins at the same speed as it orbits, so the same side always faces its planet.
• Synodic month — 29.5 days, the cycle of Moon phases from New Moon to New Moon.
• Sidereal month — 27.3 days, the time the Moon takes to orbit Earth once.
• Theia — the name scientists give to the Mars-sized body thought to have hit Earth 4.5 billion years ago, forming the Moon.
• PSR (Permanently Shadowed Region) — a crater whose floor never sees sunlight; ideal for storing water ice.

Explore Every Part of the Moon Story

Pick any topic and pull the thread. We have a full page for each one, written for kids who want to go deeper.