Q1. Answer the following questions briefly.
(a) How does a planet differ from a star?
Ans: Planet differs from star in the following manner:
|Star is big and hot celestial bodies made up of gases.||Planets are celestial bodies, smaller than stars.|
|They emit their own heat and light. Stars don’t revolve.||They are lit by the light of stars. Planets revolve around a star.|
(b) What is meant by the ‘Solar System’?
Ans: The term Solar System refers to the family of the sun. The Sun, eight planets, satellites, and some other celestial bodies known as asteroids, comets, and meteoroids together from the Solar System.
(c) Name all the planets according to their distance from the sun.
Ans: Planets according to their distance from the sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
(d) Why is the Earth called a unique planet?
Ans: Earth is called a unique planet because it is the only planet where life exists. It has favourable conditions for supporting life. The earth is neither too hot nor too cold. It has water and air, which are very essential for our survival. The air has life-supporting gases like oxygen.
(e) Why do we see only one side of the moon always?
Ans: 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.
(f) What is the Universe?
Ans: A galaxy is a huge system of billions of stars, and clouds of dust and gases. Millions of such galaxies make up the universe.
Q2. Tick the correct answer.
(a) The planet known as the “Earth’s Twin” is
Ans: (iii) Venus
Earth and its Twin
(b) Which is the third nearest planet to the sun?
Ans: (ii) Earth
(c) All the planets move around the sun in a
(i) Circular path
(ii) Rectangular path
(iii) Elongated path
Ans: (i) Elongated path
(d) The Pole Star indicates the direction to the
Ans: (ii) North
(e) Asteroids are found between the orbits of
(i) Saturn and Jupiter
(ii) Mars and Jupiter
(iii) The Earth and Mars
Ans: (ii) Mars and Jupiter
Q3. Fill in the blanks.
(a) A group of ______ forming various patterns is called a ______.
Ans: Stars, constellation
(b) A huge system of stars is called______.
(c) ______ is the closest celestial body to our earth.
Ans: The Moon
(d) ______ is the third nearest planet to the Sun.
(e) Planets do not have their own ______ and ______.
Ans: Heat, Light