Class 3 Science Chapter 14 the Earth

The Earth is made up of land and water. About 70 percent of the Earth’s surface is water and only 30 percent is land. The earth is surrounded by layer of air called the atmosphere. Our earth is the third planet from the sun. It is the only planet in the solar system which supports life. No other planet supports life. It is because air and water is available only on the earth. Moreover, the temperature of earth is also suitable for the living beings.

There are some big heavenly bodies that orbit the sun. These heavenly bodies are called planets. There are eight planets, namely, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The sun and the eight planets together form our solar system. Planets have no light of their own. They glow only when sunlight falls on them.

Millions of stars are present in the sky. They are uncountable. But there are some stars in the sky that appear in the same position. Many stars together make a definite pattern which is called constellation. Some important constellations are, namely, Ursa Major, Scorpion, Orion and Leo. There are about 88 different constellations.

The earth is round in shape looking like an orange. The first man to prove that the Earth is round in shape was Ferdinand Magellan. He sailed around the Earth in 1519. The earth looks blue from space because of the presence of water on it.

You know that the Earth moves around the Sun. It also spins on its axis. Thus, the Earth makes two kinds of movements: rotation and revolution.

The earth rotates from west to east. It completes one rotation in about 24 hours. The rotation of the Earth on its axis causes day and night.

The movement of the earth around the sun is called revolution. You will learn about it in the next classes. The earth completes its revolution in 365¼ days. Revolution of the earth causes change in season.

The people who study heavenly bodies (Sun, moon, planet and stars) are called astronomers. India has many astronomers in the past. Aryabhatta was such an astronomer in the century. He was a great mathematician. He was the first who said that the earth is round in shape and it rotates on its axis.

1. All the natural bodies present in the space are called heavenly bodies.
2. Beyond the earth’s atmosphere lies the space.
3. There are some big heavenly bodies that orbit the sun. These heavenly bodies are called planets.
4. There are eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
5. The sun and the eight planets together form our solar system.
6. Many stars together form a definite pattern called constellation.
7. The movement of the earth on its axis is called the rotation and the movement of the earth round the sun is called revolution.
8. The moon changes its shape every night.
9. Aryabhatta was the first man to tell us that the earth is round and it spins on its axis.
10. Varahmihira was a great mathematician, astronomer and astrologer.

1. A (planet/star) moves around the sun.
2. There are (nine/eight) planet in the solar system.
3. Leo is a famous (constellation/moon).
4. (Magellan/Newton) proved that the earth is round.

Answers:
1. planets
2. eight
3. constellation
4. Magellan

Answers:
1. d
2. a
3. e
4. b
5. c

heavenly bodies are called planets. For examples: earth, Jupiter, marsh, Saturn etc.

Sun and eight planets rotating around it called solar system

There are eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.