Movement of the Earth

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Rotation – Day and Night Movement of the Earth In space, the Earth moves in different ways. One way the Earth moves is Why do we experience day and night on Earth? ght oves in differen arth moves on rth? by spinning on its axis. An An axis is an axis is imaginary line that runs through the runs throug Earth’s center. This spinning movement on spinning m its axis is called a rotationa rotation. s, art of the his part of t eriences daytim opposite side ay from the darkness

As it rotates, part of the Earth is facing the Sun. This part of the Earth is lit up and experiences daytime. At the same time, the opposite side of the Earth is facing away from the Sun. This part of the Earth is in darkness and it is night-time.

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It takes the Earth 24 hours to complete one rotation. The repeating rotation of the Earth is why we experience the daily pattern of day and night.

The part of the Earth facing the Sun is in daytime. The part of the Earth facing away from the Sun is in night-time.

In what other way does the Earth move in space?Reg RIn what othe the Earth m

Amazing Fact!

The planets in the solar system rotate about their axis at different speeds. This means the length of a day on each planet is different. One day on Jupiter takes just 10 Earth hours. One day on Venus takes 243 Earth days!

Go Online!

Observe how the Earth rotates on its axis and the daily pattern of day and night on the NGScience website. QuickCode: B7M9

AB Activity 7.1

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Amazing Fact!

As the planets are different distances from the Sun, they take different times to complete an orbit. This means the length of a year is different on different planets. Mercury is the closest planet to the Sun. One year on Mercury is just 88 Earth days. On the furthest planet from the Sun, Neptune, one year is 165 Earth years!

Earth’s Orbit and Seasons

As the Earth rotates about its axis, it also o revolves in a curved path, called an orbit, rbit around the Sun. One complete orbit of the of the Sun is called a revolution. It takes the Earth the Earth 365 days to complete a revolution, which is olution, which i one Earth year.

The Earth can be divided into two parts to two part called hemispheres. The upper part of the upper part Earth is called the Northern Hemisphere. hern Hem The lower part of the Earth is called the e Earth is ca Southern Hemisphere. here

Recall that the Earth rotates about its axis. arth rotates The axis is not straight up and down. It is ot straight u tilted at an angle. This means that as the an angle. This Earth orbits the Sun, one hemisphere is its the Sun, o tilted towards the Sun and one wards the S hemisphere is tilted away from the Sun. phere is tilte The hemisphere tilted towards the Sun gets more direct sunlight than the hemisphere tilted away from the Sun. This causes changes in weather patterns in different parts of the Earth at different times of the year. These changing weather patterns are called seasons.

Go Online!

Observe the movement of the Earth around the Sun on the NGScience website. QuickCode: K8J9 ga June

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When the Northern Hemisphere is tilted towards the Sun, it gets more direct sunlight and is in summer. The Southern Hemisphere is tilted away from the Sun and gets less direct sunlight. It experiences winter.

When the Southern Hemisphere is tilted towards the Sun it is in Summer, while the Northern Hemisphere is in winter.

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Think Deeply In December, many countries in the Northern Hemisphere are in winter. What month would countries in the Southern Hemisphere be in winter? tion n er, many n the Northe e are i month would tries in the Hemisphere be

September December

How does the weather change from season to season in your area?

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