Page 192 - New Medley 3 Semester 2

We see the moon in di erent shapes on di erent nights. When the moon is

not visible at all, it is called a new moon. en, it starts increasing in size.
A er 14 days, the moon gets back into its full round shape. We now call it the

full moon. e di erent shapes of the moon are called the phases of the moon.

New moon Full moon Crescent moon
Phases of the moon
e moon is a satellite of the Earth because it revolves

around the Earth. It completes one revolution in 29
days. It is the natural satellite of the Earth.

e surface of the moon is very uneven. It has

craters, mountains and rocks.

ere is no water and air on the moon. Astronauts
have to carry their own food, water and oxygen. Craters on the surface of the moon

PLANETS

Just like the moon revolves around the Earth, the Earth revolves around the sun.

e heavenly body that revolves around the sun is called a planet. ere are

eight planets, including the Earth, that revolve around the sun. Most planets
have their natural satellites like the Earth.

Knowledge Zone

There are man-made satellites, called artificial satellites. These are sent into the outer
space. These move around the Earth and study the Earth’s atmosphere.

THE SOLAR SYSTEM

e sun, the eight planets, their satellites and some other heavenly bodies form

the solar system. In the solar system, the sun is at the centre and all the planets
revolve around it.

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