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Earth

Earth is the third planet from the sun. As it is at the right distance from the

Sun, it’s neither too hot nor too cold. It

has air and water, and it is the only planet

in the solar system that supports life. It is

known as the blue planet because three-
fourths of its surface is covered with

water, giving it a blue colour. A thin layer

of air surrounds the Earth. This layer,
known as the atmosphere, is made up of

several gases.

Think &
Answer Do planets other than Earth have air and water? Can we live on other planets?

Shape of the Earth

The Earth’s shape is not a perfect sphere. The Earth is flat at the poles but

slightly bulges at the equator. Though the Earth looks very big, compared

to the Sun and other stars, it is very small.

In the olden days, people used to think that the Earth was flat, but now it

is clear that the Earth is spherical.

Many sailors in the olden days started their journey from a particular point.

After sailing for many days, they reached the same point from where they
had begun. This proved that the Earth is spherical.

When American astronauts landed on the moon in 1969, they discovered
that the Earth was spherical. They had taken photographs from space to

prove the shape of the Earth.

Movements of the Earth

Even though we cannot feel it, the Earth is moving all the time. The Earth

has two types of movements – rotation and revolution.

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