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Chapter-1 The Earth in the Solar System

Chapter-1 The Earth in the Solar System

1. Answer the following questions briefly.

Question a:- How does a planet differ from a star?
Answer:- Planet differs from star in the following manner: Planet does not have its own light while star emits their own light. Planet revolves around a star while star does not revolve around any celestial bodies. Planet does not twinkle while star does.

Questions b:- What is meant by the ‘Solar System’?
Answer:- The system formed by the sun, eight planets, satellites, asteroids and various other celestial bodies is called the Solar System.

Question c:– Name all the planets according to their distance from the sun.
Answer:- Planets according to their distance from the sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

Questions d:– Why is the Earth called a unique planet?
Answer:- Conditions favourable to support life are probably present only on Earth. The Earth is neither too hot nor too cold. It has water and air, which are very essentialfor our survival. The air has life-supporting gases like oxygen. Because of thesereasons, the Earth is a unique planet in the solar system.

Question e:- Why do we see only one side of the moon always?
Answer:- The moon moves around the earth in about 27 days. It takes exactly the same time to complete one spin. Therefore, only one side of the moon is visible to us on the earth.

Question f :– What is the Universe ?
Answer :- A galaxy is a huge system of billions of stars, and clouds of dust and gases.  Millions of such galaxies make up the universe.

2. Tick the correct answer.

(a) The planet known as the “Earth’s Twin” is
(i) Jupiter
(ii) Saturn
Ans:- (iii) Venus

(b) Which is the third nearest planet to the sun ?
(i) Venus
Ans:- (ii) Earth
(iii) Mercury

(c) All the planets move around the sun in a
(i) Circular path
(ii) Rectangular path
Ans:- (iii) Elongated path

(d) The Pole Star indicates the direction to the
(i) South
Ans:-(ii) North
(iii) East

(e) Asteroids are found between the orbits of
(i) Saturn and Jupiter
Ans:- (ii) Mars and Jupiter
(iii) The Earth and Mars

3. Fill in the blanks.

(a) A group of stars forming various patterns is called a constellation .
(b) A huge system of stars is called galaxy .
(c) The Moon is the closest celestial body to our earth.
(d)Earth is the third nearest planet to the sun.
(e) Planets do not have their own heat and light .