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We live on planet Earth which circles around the Sun, our source of heat and light.

In this Space article you will find out about:

• what the Earth, Sun and Moon are and how they are different from each other
• why we experience day and night
• what causes the different seasons
• the movement and shapes of the Moon

We live on Earth. It is a planet made of rock and metals.

The Earth circles around the Sun in a path called an orbit. The Sun is a star made of hot, glowing gases.

The Moon is a satellite made of rock. Just like the Earth orbits the Sun, the Moon orbits the Earth.

The Earth, Sun and Moon are all spheres – the shape of a ball. But they are very different sizes.

• The Sun is 109 times wider than Earth
• The Earth is more than three times the width of the Moon

The Earth is always spinning around on its axis (an imaginary line going through the Earth from the North Pole to the South Pole).

It takes the planet 24 hours to spin all the way round once. That's why one full day (including night) takes 24 hours.

• when part of the Earth faces the Sun and gets lit up it is daytime.
• when part of the Earth faces away from the Sun it is in darkness. This is night.

Because the Earth is always slowly spinning, everywhere on Earth turns in and out of the light from the Sun, moving between day and night.

As well as the Earth spinning on its axis, at the same time it is also orbiting the Sun.

The Earth takes 365 and a quarter days to make one complete orbit of the Sun. This is why a year on Earth is 365 days long.

(The extra quarter day is the reason why we have a 366 day leap year every four years.)

The Earth’s axis is slightly tilted. This tilt gives us our seasons.

The four seasons are spring, summer, autumn and winter.

• Winter is when the northern hemisphere (where we live) is tilted away from the Sun. Sunlight hits the northern hemisphere at a shallow angle. This spreads sunlight over a wide area so it is weaker and less warm. Winter has the coldest weather and the longest nights of the year.

• Spring is when the northern hemisphere begins to tilt towards the Sun. Longer days with stronger sunlight make the weather warmer and brighter. This helps plants to grow.

• Summer is when the northern hemisphere is tilted towards the Sun - this gives us longer days and means the Sun's rays are more direct, stronger and warmer.

• Autumn is when the northern hemisphere begin to tilt away from the Sun. Days become shorter and the Sun's light hits the northern hemisphere at a shallower angle. This makes it weaker and so the weather gets colder. The shorter days cause the leaves on trees to change colour.

Look at how the Earth's tilt changes how much sunlight the northern hemisphere receives.

The Moon is always a sphere but you may have seen different shapes of Moon in the sky. These are called the Moon's phases.

The Moon does not make its own light like a star. The Moon appears bright because it reflects light from the Sun. Like the Earth, half of the Moon faces towards the Sun, and half faces away from it.

As the Moon orbits the Earth, we see it from different angles. We see different amounts of the lit and dark side, and this is what causes the phases of the Moon:

This diagram shows how the Moon appears to change shape as it orbits (circles) the Earth due to which part of it is facing the Sun.

• 🌕 Full Moon is when we can only see the side of the Moon that is lit up by the Sun.
• �д New Moon is when we can only see the side of the Moon that is in shadow because it is facing away from the Sun.
• 🌗 Half Moon when we the Moon is side on, and we see half of the lit side and half of the side in shadow.
• �� Crescent Moon is when we only see a small edge of the lit side and mostly see the part of the Moon that is in shadow.
• 🌔 Gibbous Moon is when we mostly see the lit side of the Moon but we can also see part that is in shadow.

When the lit area of the Moon we see is getting bigger each day, we say the Moon is waxing.When the lit area of the Moon we see is getting smaller, we say the Moon is waning.

It takes just over 27 days for the Moon to orbit (go around) the Earth.It takes a little longer, 29.5 days, for the Moon to go through all of its phases.

The Moon is made of rock. Its surface has different shapes and patterns on it.

Some markings are craters caused by asteroids or meteors crashing into the Moon.

You might be able to see some craters just with your eyes.

If you can use binoculars or a telescope, you should be able to see craters more clearly.

Here is an activity to investigate how the craters of the Moon are made.

What you need:

• shallow metal pan or tray

• flour

• chocolate powder

• marbles or different sized balls

Making craters

1. Fill the pan about 2 cm deep with flour
2. Lightly sprinkle drinking chocolate to cover the entire surface.
3. Drop the marbles or balls into the pan.
4. Notice how the marbles make craters in the pan. The white flour is brought to the surface.
5. Try dropping different sizes and weights of balls from different heights and angles. See if the craters are deeper or different shapes.

The marbles act as the asteroids and comets crashing into the Moon's surface.

You should notice that it isn't just the size of the object that affects the size of crater. It's mass and the speed it hits the surface at also make a difference.