CBSE – 8th Standard Science

CBSE - 8th Standard Science

Question Bank – Chapter 17 – Stars and Solar System

Chapter 17

Stars and solar system

Q1. In which part of the sky can you find Venus if it is visible as an evening star?

Ans. Venus is visible in the western part of sky as an evening star Venus is earth’s nearest planetary neighbor. It is the brightest planet in the night sky. Sometimes Venus appears in the eastern sky before sunrise and sometimes it appears in the western sky just after sunset. Therefore it is called  morning or an evening star.


Q2.  What are celestial objects and what force works between our solar system?

Ans. The stars, the planets, the moon and many other objects in the sky are called celestial objects.The gravitational attraction between the Sun and celestial bodies keeps them revolving around it.


Q3. Name the largest planet of the solar system.

Ans. Jupitor is the largest planet, it is so large that about 1300 earths can be placed inside Jupiter has a large number of satellites. It also has faint rings around it.


Q4. What is a Satellite?

Ans. A body revolving around another body is called a satellite. Moon is a natural satellites, And some man made satellite are also in the sky.


Q5. What is the period of  rotation and revolution?

Ans. The time taken by a planet to complete one revolution is its period of revolution.The time taken by a planet to complete one rotation on its own axis is the period of rotation


Q6. What is a constellation? Name any two constellations.

Ans. The stars forming a group that has a recognisable shape is called a constellation. Orion is a well-known constellation that can be seen during winter in the late evenings and Ursa Major are well known constellation.


Q7. Name two objects other than planets which are members of the solar system. .

Ans. Comets and Asteroids .A large gap in between the orbits of Mars and Jupiter is occupied by a large number of small objects that revolve around the Sun. These are called asteroids are also the member of solar system. A Comet appears generally as a bright head with a long tail.


Q8. Explain how you can locate the Pole Star with the help of Ursa Major.

Ans. Ursa major moves around the pole star, The pole star, is situated in the direction of the earth’s axis,it does not appear to move.


Q9.  Why is the distance between stars expressed in light years?

Ans. The stars are millions of times farther away than the Sun. Distance between stars is expressed in unit known as light year. It is the distance traveled by light in one year


Q10. How can we identify planets and stars?

Ans. The simplest method of identifying planets from stars is that stars twinkle, whereas planets do not, planets keep changing their positions with respect to the stars.


Q11. Does on Venus, the Sun would rise in the west and set in the east?

Ans. Rotation of Venus on its axis is somewhat unusual, It rotates from east to west while the Earth rotates from west to east thus it is possible that un would rise in the west of Venus and set in the east.


Q12. What is a difference between inner planets and outer planets of our solar system?

Ans. The first four planets, are inner planet and they have very few moons while planets outside the orbit of Mars, are called Outer planet, they have a ring system with large number of moons.


Q13. What are Meteorites?

Ans. Meteors are very small object but when a meteor is large so that it can reach the Earth before evaporates completely that body reaches on Earth is called a meteorite.

When the Earth crosses the tail of a comet, swarms of meteors are seen. These are known as meteor showers. Some meteor showers occur at regular intervals each year.


Q14. What are practical applications of Artificial satellites?

Ans. Artificial Satellites are used for forecasting weather, transmitting television and radio signals. They are also used for remote sensing and telecommunication.


Q15. What are artificial satellites? Give some examples?

Ans. The artificial satellites are man-made. They are launched from the Earth. They revolve around the Earth much closer than moon. Aryabhatta was the first Indian satellite. Some other Indian satellites are INSAT, IRS, Kalpana-1, EDUSAT, they are used for forecasting weather, transmitting television and radio signals.


Try these :-

Why is Pluto not considered as a planet anymore?

Compare stars and planets?

 Differentiate between meteors and comets?

Match the column :-

  1. mercury i) brihaspati
  2. Jupiter  ii) shani
  3. venus  iii) Saptarishi
  4. Saturn  iv) budh
  5. Ursa Major  v) shukra