NCERT Solution Class 6 Social Science Geography

Chapter 1: The Earth in the Solar System

Answer the following questions briefly.

(a) How does a planet differ from a star?

Answer: The difference between a planet and a star are:

(b) What is meant by the 'Solar System'?

Answer: Solar system is often termed as a family with Sun as its head. It is a system that contains eight planets, Sun, satellites, celestial bodies like meteoroids and asteroids.

(c) Name all the planets according to their distance from the sun.

Answer: The planets according to their distance from the sun are:

• Mercury
• Venus
• Earth
• Mars
• Jupiter
• Saturn
• Uranus
• Neptune

Thus, we can conclude that mercury is the nearest planet from the sun and Neptune is the farthest planet from the sun.

(d) Why the Earth is called a unique planet?

Answer: Earth is called a unique planet because,

• It is the only planet in the solar system that supports life. It has life supporting conditions like oxygen, air, and water.
• The temperature is neither too hot nor too cold.
• It is also known as the blue planet because its two-third surface area is covered by water.

(e) Why do we see only one side of the moon always?

Answer: The time taken by the moon to spin on its axis is the same as the time it takes to orbit the Earth. Hence, we can see only one side of the moon.

(f) What is the universe?

Answer: The millions of galaxies collectively make a universe. A galaxy is a collection of billions of stars, multiple planets, celestial bodies, clouds of dust and gases.

Tick the correct answers.

(a) The planet known as the "Earth's twin" is:

1. Jupiter
2. Saturn
3. Venus

Answer: (iii) Venus

Explanation: Venus is known as the Earth's twin because its size and shape is similar to the Earth.

(b) Which is the third nearest planet to the sun?

1. Venus
2. Earth
3. Mercury

Answer: (ii) Earth

Explanation: The Earth is the third nearest planet to the sun.

(c) All the planets move around the sun in a

1. Circular path
2. Rectangular path
3. Elongated path

Answer: (iii) Elongated path

Explanation: All the planets move around the sun in an elongated path known as orbits.

(d) The pole star indicates the direction to the

1. South
2. North
3. East

Answer: (ii) North

Explanation: The pole star in the sky indicates the north direction.

Fill in the Blanks.

1. A group of stars forming various patterns is called a constellation.
2. A huge system of stars is called galaxy.
3. Moon is the closest celestial body to our Earth.
4. Earth is the third nearest planet to the sun.
5. Planets do not have their own heat and light.