Text size
Line height
Text spacing
What is Earth
Completion requirements
What is Earth
Last modified: Monday, 6 April 2026, 2:29 PM
What is the Earth?
The Earth
The Earth is one of the planets that form part of our Solar System. It is mostly made of rock rather than gas like some other planets.
It looks like a giant sphere in space.
It is the only planet that is known to be able to support life because it is just the right distance from the Sun so that it is not too hot and not too cold. This means that the water on Earth mostly stays as a liquid, rather than frozen as ice or evaporating as a gas.
The water on the Earth is important to allow living things to survive.
Watch: What is the Earth?
Fascinating facts
- Water covers about 70% of the Earth's surface and almost all of this is salt water in the oceans.
- Planet Earth is about 4.5 billion years old.
- The Earth is the third closest planet to the Sun.
- It takes Earth just one year (365 days) to orbit the Sun.
- As well as orbiting the Sun, the Earth rotates on its axis at 1000 miles an hour, completing one full rotation in 24 hours.
- The Earth isn't actually perfectly round. Its rotation causes it to flatten slightly at the poles and bulge at the equator, not to mention the various mountains and volcanoes on the surface!
- Earth is the fifth largest planet in the Solar System.
- Earth is the only planet in the Solar System that has just one moon.
The Earth is the third planet from the Sun
The Earth and the Sun
The Earth is constantly spinning. We can't fee it spinning but it is actually moving at 1000 miles an hour.
It takes 24 hours for the Earth to do one full rotation on its axis and get back to the point that it started from. This is what makes a day.
When the Earth rotates, one side will be facing the Sun and it will be daytime in these countries.
On the opposite side of the Earth, the countries that are facing away from the Sun will be dark and it will be night-time.
The Earth, along with the rest of the other planets in our Solar System, orbit the Sun. Each planet takes a different amount of time to travel around the Sun once, depending on how close they are to it.
The Earth takes about 365.25 days to orbit the Sun which is one year.
When you look at a model of the Earth or a globe, they are usually mounted straight with the north pole right at the top of the globe and the south pole right at the bottom with the axis straight through the middle.
However, in real life the Earth is actually tipped over at an angle of 23.5 degrees from upright.
The tilt of the Earth means that as it orbits the Sun, the northern and southern hemisphere get different amounts of sunshine at different times of the year.
This creates the different seasons.
The side of the Earth facing the Sun is in daytime, the side facing away is in night-time
The Earth is tipped over at an angle of 23.5 degrees from upright
The four seasons
Spring
When it is spring, day and night are about the same length. The days are starting to become longer as we move towards the summer.
Summer
In summer, the hemisphere is tilted slightly towards the Sun, so the days are longer and it is warmer.
Autumn
When it is autumn the days and nights are about the same in length. The days are starting to grow shorter as we move towards winter.
Winter
In winter, the hemisphere is tilted slightly away from the Sun, so the days are shorter and it is colder
The four seasons
The name 'Earth', was taken from Old English and Germanic. It simply means "the ground." It is the only planet name in our Solar System that does not come from Greco-Roman mythology.
The names of other planets, such as Jupiter and Saturn, come from Greco-Roman mythology.
The name 'Saturn' comes from Greco-Roman mythology
What is the Earth?
The Earth
Planet Earth is about 4.5 billion years old and is the third planet from the Sun. It is the only planet in our Solar System that supports life.
A year
It takes Earth just one year to orbit the Sun and 24 hours to fully rotate on its axis.
Daytime
When the Earth rotates on its axis, half the Earth is facing the Sun which means it is daytime.
Night-time
The other half of the Earth that faces away from the Sun is in darkness, so it is night-time.
Did you know?
A year on Earth is usually 365 days long, but because the Earth takes 365 and a quarter days to orbit the Sun, we add the four quarters of a day together to create a whole extra day once every four years.
We add this on to February so we have February 29th once every four years. We call this a leap year!
The Earth takes 365 days to orbit the Sun
The Earth and the Moon
The Earth is the only one of the rocky planets to have its own natural satellite.
It is called the Moon.
The Moon is a large sphere shaped lump of rock which is about a quarter the size of the Earth. It is covered in craters; lots of dents and holes caused by other objects in space crashing into it.
The Moon orbits the Earth, taking 27 and a half days to travel all the way around.
It is held the right distance away from the Earth by the Earth's gravity.
The Moon cannot make its own light so even though the Moon looks like it is shining into the night sky, it is actually just reflecting the light from the Sun.
The Moon is around one quarter the size of Earth
Day and night
When the Earth rotates on its axis, half the Earth is facing the Sun which means it is daytime.
The other half facing away from the Sun is in darkness so it is night-time.
Did you know?
Modern humans have only been on the Earth for around 200,000 years. Before that, our ancestors would have been around for nearly 6 million years which is a short time considering the Earth is almost 4.5 billion years old.
