What Does the Moon Do? Look up on any clear night, and you’ll find it: a bright, silent disc hanging in the dark. The Moon is Earth’s only natural satellite and has been orbiting our planet for roughly 4.5 billion years. Yet for something so familiar, it does far more than light up the sky. The Moon actively shapes conditions on Earth, from the rhythm of the tides to the stability of our seasons. Understanding what it does and why is a core part of the UK KS2 Year 5 Science curriculum in Earth and Space.
At LearningMole, we know that space topics capture children’s imaginations faster than almost any other subject. The Moon is where that curiosity often begins. It’s visible to the naked eye, it changes shape across the month, and it connects directly to the kind of scientific observation children can carry out at home. That makes it an ideal starting point for developing scientific thinking as well as factual knowledge.
This guide covers what the Moon actually does for Earth, how it moves, its phases, its surface, and 16 specific facts that go beyond the basics. Whether you’re a teacher planning a Year 5 Earth and Space unit, a parent supporting homework, or a curious child who just wants to know why the Moon looks different each night, you’ll find straightforward answers here, mapped clearly to the curriculum.
The Moon performs three critical jobs for our planet: it controls the tides, it stabilises Earth’s axial tilt, and it slows down Earth’s rotation over geological time. Without it, life on Earth would look very different.
The Moon’s gravitational pull draws Earth’s oceans towards it, creating a bulge of water on the side of the planet closest to the Moon. There is a corresponding bulge on the opposite side due to inertia. As Earth rotates, different coastlines pass through these bulges, producing high and low tides roughly twice a day.
This tidal rhythm governs coastal ecosystems, the feeding cycles of shore-dwelling animals, and the lives of communities that fish and sail around the UK’s coastline. Spring tides, when the Sun and Moon align, produce the biggest tidal ranges, which is why places like the Severn Estuary see some of the highest tides in the world.
Earth’s axis is tilted at about 23.5 degrees, and that tilt gives us our seasons. The Moon’s gravitational influence keeps that tilt relatively steady. Without the Moon stabilising it, Earth’s axial tilt could vary dramatically over tens of thousands of years, ranging from roughly 0 degrees to 85 degrees. A 0-degree tilt would mean no seasons at all, while an 85-degree tilt would produce extreme climate swings that would make stable ecosystems almost impossible to maintain. The Moon, in other words, is part of why Earth has been habitable long enough for complex life to evolve.
The Moon’s gravitational drag is gradually slowing Earth’s rotation. Each century, a day grows about 2.3 milliseconds longer. Over hundreds of millions of years, that adds up: scientists calculate that in around 200 million years, a day on Earth will last 25 hours. As Earth loses rotational energy to the Moon, the Moon drifts further away, gaining energy in return. It moves about 3.8 centimetres further from Earth each year.
Moonlight plays a meaningful role in animal behaviour. Many species use the lunar cycle to time migration, reproduction, and feeding. Sea turtles use a bright full moon to navigate to nesting beaches. Coral spawning events on the Great Barrier Reef are timed to the lunar calendar. Even insects and nocturnal predators adjust their behaviour across the lunar month. This ecological function means the Moon is far more than a decorative fixture in the night sky.
| Feature | The Moon | The Earth |
|---|---|---|
| Diameter | 3,474 km | 12,742 km |
| Surface temperature (day) | Up to 127 °C | Average 15 °C |
| Surface temperature (night) | Down to -173 °C | Average 15 °C |
| Atmosphere | None | Nitrogen and oxygen |
| Gravity (compared to Earth) | About 1/6th | 1 (full gravity) |
| Length of day | 29.5 Earth days | 24 hours |
| Natural satellites | None | One (the Moon) |
| Distance from Earth | 384,400 km average | — |
These facts go beyond the standard introduction to give children, teachers, and parents a richer picture of Earth’s nearest neighbour.
A natural satellite is any space body that orbits a planet under gravity. Earth has just one. This is a key definition for the KS2 Year 5 Science curriculum.
It is bigger than Pluto and about one-quarter the size of Earth. You could fit roughly 50 Moons inside the Earth by volume.
Without an atmosphere to burn up incoming debris, meteorites crash directly into the surface, creating the craters we can see from Earth. There is no wind or rain either, which is why astronaut footprints from the Apollo missions are still perfectly preserved today.
Astronauts who walked on the Moon reported that the dust carried inside on their suits had a distinctive burnt, metallic smell, similar to gunpowder. Scientists believe this is caused by high-energy particles from the Sun chemically altering the surface material.
When Apollo astronauts deliberately crashed a lunar module onto the Moon’s surface in 1969, seismometers recorded the Moon vibrating for over an hour. This behaviour led scientists to describe it as “ringing like a bell”, suggesting the interior is more rigid and less layered than Earth’s.
The Moon drifts about 3.8 centimetres further from Earth every year. Over billions of years, this means the Moon will eventually be too far away to cause total solar eclipses.
The Moon rotates on its axis in exactly the same time it takes to orbit Earth (about 27.3 days). This is called synchronous rotation, and it means the far side of the Moon was unseen by humans until a spacecraft first photographed it in 1959.
Precise measurements show the Moon bulges slightly towards Earth. It is an oblate spheroid with a subtle elongation, though it looks round from Earth.
A solar eclipse requires the Moon to pass directly between Earth and the Sun. This alignment is only possible when the Moon is in its new moon phase, on the side of Earth facing the Sun.
A lunar eclipse requires Earth to pass directly between the Sun and the Moon, blocking sunlight from reaching the Moon’s surface. This geometry only occurs during the full moon phase.
When Earth’s shadow fully covers the Moon, a small amount of sunlight still reaches the Moon’s surface after passing through Earth’s atmosphere. The atmosphere scatters shorter wavelengths of light, allowing red wavelengths through. This is why the Moon appears deep red or orange, giving rise to the name “Blood Moon”.
The lunar cycle lasts about 29.5 days. February, with 28 or 29 days, is short enough that a full moon can fall just before the month starts and just after it ends, leaving no full moon in between. This is extremely rare.
All twelve were American astronauts, and all walked on the Moon between 1969 and 1972 during the Apollo programme. The last person to walk on the Moon was Eugene Cernan of Apollo 17, in December 1972.
The Moon travels at roughly 3,683 kilometres per hour in its orbit. That is about three times faster than a rifle bullet.
The leading scientific theory, known as the Giant Impact Hypothesis, suggests that around 4.5 billion years ago, a Mars-sized object collided with the young Earth. The debris from that collision eventually came together to form the Moon.
NASA’s LCROSS mission in 2009 confirmed the presence of water ice in permanently shadowed craters near the Moon’s south pole. This discovery is significant for future lunar exploration: ice could be converted into drinking water, oxygen, and hydrogen fuel for spacecraft.
The Moon appears to change shape each night because we see different amounts of its sunlit surface as it orbits Earth. The Moon itself is not changing; our angle of view is. Over roughly 29.5 days, the Moon passes through eight recognised phases.
| Phase | What You See |
|---|---|
| New Moon | Moon not visible (unlit side faces Earth) |
| Waxing Crescent | A thin crescent, growing larger each night |
| First Quarter (Half Moon) | Right half lit (visible roughly a week after new moon) |
| Waxing Gibbous | More than half lit, still growing |
| Full Moon | Entire lit surface visible; rises at sunset, sets at sunrise |
| Waning Gibbous | More than half lit, but shrinking each night |
| Last Quarter (Half Moon) | Left half lit |
| Waning Crescent | A thin crescent, shrinking towards new moon |
Waxing means growing (the lit area increases). Waning means shrinking (the lit area decreases). The word “gibbous” describes a shape that is more than half but not fully lit. These vocabulary terms are useful for Year 5 and Year 6 science lessons.
Teacher tip: Give each child an Oreo biscuit and ask them to scrape away the cream filling to model each phase. It is a practical, low-cost activity that makes the waxing and waning sequence memorable and connects visual observation to the correct vocabulary.
This activity develops scientific observation and recording skills, both key elements of Working Scientifically in the KS2 curriculum.
What children need: A notebook, a pencil, and a clear view of the sky each evening for 28 days.
The Moon appears explicitly in the KS2 Science programme of study under Earth and Space, which is typically taught in Year 5. The curriculum requires children to describe the movement of the Moon relative to Earth, understand the Moon as Earth’s natural satellite, and explain what is meant by a year and a day in terms of planetary and lunar movement.
| Curriculum Requirement | How This Article Supports It |
|---|---|
| Describe the movement of the Moon relative to Earth | Orbital period (27.3 days), synchronous rotation, phases explained |
| Understand the Moon as Earth’s natural satellite | Definition provided; distinction from planets and stars |
| Explain the apparent changes in the Moon’s shape | Eight phases explained with correct vocabulary (waxing, waning, gibbous) |
| Use the context of day and night and Earth’s rotation | Earth’s rotation, day length, and the Moon’s slowing effect covered |
| Working Scientifically: observing and recording | Earth’s rotation, day length, and the Moon’s slowing effect are covered |
LearningMole provides curriculum-aligned video resources and teaching materials for primary schools across the UK. Our Earth and Space content is designed to support teachers delivering the KS2 Year 5 Science unit, with visual explanations and age-appropriate language that works for whole-class teaching or independent learning at home.
For parents supporting home learning, LearningMole’s resources cover the core concepts children meet in school, including the Moon’s phases, the Solar System, and Earth’s movement. Our videos explain complex ideas visually, which suits children who find abstract descriptions harder to follow.
“Space is one of those topics where the ‘wow’ comes first and the science follows naturally. Children don’t need persuading to care about the Moon. Our job as educators is to channel that natural curiosity into solid scientific understanding, connecting what they can see in the night sky to what the curriculum asks them to know.” — Michelle Connolly, Founder of LearningMole and former teacher with over 15 years of classroom experience
The Moon is Earth’s only natural satellite: a rocky body that orbits our planet under the force of gravity. It is about a quarter the size of Earth and sits, on average, 384,400 kilometres away. The Moon has no atmosphere, no liquid water on its surface, and no active volcanoes. It formed approximately 4.5 billion years ago, most likely from debris produced when a large object collided with the early Earth.
The Moon provides three main things for Earth. It creates tides by exerting gravitational pull on the oceans, which sustains coastal ecosystems and has shaped human navigation for thousands of years. It stabilises Earth’s axial tilt, which keeps our seasons relatively consistent rather than swinging to extremes. It also provides moonlight, which many animals rely on for navigation and reproduction. Without the Moon, the night sky would be far darker, tidal patterns would be dramatically weaker, and Earth’s climate history might have been far less stable.
The Moon does not change shape. What changes is how much of the sunlit side we can see from Earth as the Moon orbits us. When the Moon is between Earth and the Sun, we see the unlit side (new moon). When Earth is between the Moon and the Sun, we see the fully lit side (full moon). At all points in between, we see a partial view, producing the crescent, quarter, and gibbous shapes. The complete cycle of eight phases takes about 29.5 days.
The Moon is about 400 times smaller than the Sun in diameter. It only appears a similar size in our sky because it is roughly 400 times closer to Earth than the Sun is. This extraordinary coincidence means the Moon can precisely cover the Sun during a total solar eclipse. As the Moon slowly moves further from Earth over millions of years, total solar eclipses will eventually become impossible.
The Moon rotates on its own axis once in exactly the same time it takes to complete one orbit of Earth (approximately 27.3 days). This is called synchronous rotation, and it is not a coincidence. It is the result of tidal locking: Earth’s gravity has, over billions of years, slowed the Moon’s rotation until it matched its orbital period. The result is that one side of the Moon always faces Earth, while the far side remains permanently turned away from us. The far side was first photographed by the Soviet Luna 3 mission in 1959.
Without the Moon, Earth’s tides would be dramatically reduced, driven only by the Sun, which has a weaker tidal effect. More significantly, Earth’s axial tilt would become unstable over long periods, shifting between extremes that could produce severe climate changes. Many species that rely on moonlight, tides, or the lunar cycle for reproduction and navigation would face serious disruption. The Moon is deeply embedded in Earth’s ecological and geological systems.
Yes. The content in this article is specifically written to support the KS2 Year 5 Science curriculum unit on Earth and Space. It covers the Moon as Earth’s natural satellite, orbital movement and rotation, the phases of the Moon, and the Moon’s effects on Earth, all of which appear in the national curriculum programme of study. The Moon Diary activity and vocabulary explanations (waxing, waning, gibbous) are also relevant to working scientifically objectives.
Twelve people have walked on the Moon, all during NASA’s Apollo programme between 1969 and 1972. Neil Armstrong and Buzz Aldrin were the first to land on 20 July 1969 during the Apollo 11 mission. The last people to walk on the Moon were Eugene Cernan and Harrison Schmitt of Apollo 17 in December 1972. No human has walked on the Moon since then, though NASA’s Artemis programme is developing missions that aim to return astronauts to the lunar surface, including the first woman to walk on the Moon.
The Moon is far more than a bright light in the night sky. It controls the rhythm of the tides, keeps Earth’s axial tilt stable enough for consistent seasons, and has shaped the behaviour of countless species over billions of years. For children learning about Earth and Space in Year 5, understanding the Moon means understanding the conditions that make Earth habitable. That is a genuine scientific insight, not just a collection of facts.
The 16 facts in this guide are designed to go beyond what most Moon articles offer: not just size and distance, but the smell of moon dust, the ringing of the lunar surface, the water ice in permanently shadowed craters, and the slow drift away from Earth that will, in millions of years, change the nature of eclipses. These details make the Moon memorable and give children something specific to think about and discuss.
LearningMole’s curriculum-aligned resources for primary schools cover Earth and Space alongside the full breadth of KS1 and KS2 science. If you’re a teacher planning a Year 5 unit or a parent supporting learning at home, our video resources and teaching materials are designed to make complex ideas accessible without oversimplifying what children need to know.
LearningMole provides free and subscription-based educational videos and resources aligned with the UK National Curriculum. Our KS2 Science materials cover Earth and Space, alongside maths, English, and more.
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