1.Which of the following is NOT a member of the solar system?
(a) An asteroid
(b) A satellite
(c) A constellation
(d) A comet
A.(c) Constellation
(b) Mercury
(c) Saturn
(d) Earth
A.a) Sirius
3.Phases of the moon occur because
(a) we can see only that part of the moon which reflects light towards us.
(b) our distance from the moon keeps changing.
(c) the shadow of the Earth covers only a part of the moon’s surface.
(d) the thickness of the moon’s atmosphere is not constant.
A..in the western sky after sunset and is called the evening star.
6.What is a constellation? Name any two constellations.
A..A constellation is a group of stars that form a recognisable pattern in the sky. The two well known constellations are Ursa Major and Orion.(DRAW FROM TEXT)
7. Define asteroids & mateors
This imaginary line meets a star called the Pole Star. The length of the imaginary line from the bowl is about five times the distance between the two stars of the bowl.
9.Do all the stars in the sky move? Explain
A..No. The Earth rotates from West to East on its axis. Hence, all stars in the sky (except the Pole star) appear to move from East to West. With reference to the Earth, the Pole star does not appear to move in the sky because it is located above the axis of rotation of the Earth in the north direction. It appears to remain stationary at a point in the sky
10..Why is the distance between stars expressed in light years? What do you understand by the statement that a star is eight light years away from the Earth?
A..The distance of the stars from the Earth and the distance between the stars are very large. It is inconvenient to express these distances in kilometer (km). Thus, these large distances are expressed in light years. One light year is the distance travelled by light in one year. One light year is equal to 9.46 × 1012 km.
(a) An asteroid
(b) A satellite
(c) A constellation
(d) A comet
A.(c) Constellation
constellation is not a member of the solar system. Constellations are groups of stars that form recognisable shapes.
2.Which of the following is NOT a planet of the sun?
(a) Sirius(b) Mercury
(c) Saturn
(d) Earth
A.a) Sirius
3.Phases of the moon occur because
(a) we can see only that part of the moon which reflects light towards us.
(b) our distance from the moon keeps changing.
(c) the shadow of the Earth covers only a part of the moon’s surface.
(d) the thickness of the moon’s atmosphere is not constant.
A.(a) Phases of the moon occur because we can see only that part of the moon which reflects light towards us
4.Fill in the blanks:
(a) The planet which is farthest from the sun is _________.
(b) The planet which appears reddish in colour is _________.
(c) A group of stars that appear to form a pattern in the sky is known as a __ _________.
(d) A celestial body that revolves around a planet is known as a _________.
(e) Shooting stars are actually not _________.
(f) Asteroids are found between the orbits of ________ __ and _________.
A.a) The planet which is farthest from the sun is __Neptune__.
(b) The planet which appears reddish in colour is __Mars__.
(c) A group of stars that appear to form a pattern in the sky is known as a __constellation__.
(d) A celestial body that revolves around a planet is known as a satellite_.
(e) Shooting stars are actually not stars __.
(Shooting stars are not stars, they are meteors)
(f) Asteroids are found between the orbits of __Mars __ and __Jupiter.
(Asteroids occupy a large gap between the orbits of Mars and Jupiter)
5.In which part of the sky can you find Venus if it is visible as an evening star?
6.What is a constellation? Name any two constellations.
A..A constellation is a group of stars that form a recognisable pattern in the sky. The two well known constellations are Ursa Major and Orion.(DRAW FROM TEXT)
7. Define asteroids & mateors
A..
i) Asteroids
A collection of a large number of small objects, gases and dust are revolving around the sun. They occupy a large gap between the orbits of Mars and Jupiter. However, these are not planets. These celestial objects are known as asteroids.
(ii) Meteors
Meteors are small celestial objects that are seen as bright streaks of light in the sky.
They brunt out on entering the Earth’s atmosphere because of the heat produced by friction. This results in bright streaks in the sky. They are not planets.
8.Explain how you can locate the Pole Star with the help of Ursa Major
A..In order to locate the Pole star in the sky, first of all Ursa Major or Big Dipper constellation mustbe located. The bowl of the Big Dipper consists of four bright stars 
Consider two stars at the end of this bowl. Now, draw an imaginary straight line towards the Northern direction connecting these two stars (as shown in the given figure).
Consider two stars at the end of this bowl. Now, draw an imaginary straight line towards the Northern direction connecting these two stars (as shown in the given figure).This imaginary line meets a star called the Pole Star. The length of the imaginary line from the bowl is about five times the distance between the two stars of the bowl.
9.Do all the stars in the sky move? Explain
A..No. The Earth rotates from West to East on its axis. Hence, all stars in the sky (except the Pole star) appear to move from East to West. With reference to the Earth, the Pole star does not appear to move in the sky because it is located above the axis of rotation of the Earth in the north direction. It appears to remain stationary at a point in the sky
10..Why is the distance between stars expressed in light years? What do you understand by the statement that a star is eight light years away from the Earth?
A..The distance of the stars from the Earth and the distance between the stars are very large. It is inconvenient to express these distances in kilometer (km). Thus, these large distances are expressed in light years. One light year is the distance travelled by light in one year. One light year is equal to 9.46 × 1012 km.
A star is located eight light years away from the Earth. This means that the distance between the star and the Earth is equivalent to the distance travelled by light in eight years, i.e., a star is located 8 × (9.46 × 1012) = 7.6 × 1013 km away from the Earth.
11.
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