Study Materials

NCERT Solutions for Class 8th Science


Page 1 of 5

Chapter 17. Stars And The Solar System

Chapter Review




Chapter Review:

  • The stars, the planets, the moon and many other objects in the sky are called celestial objects.
  • The day on which the whole disc of the moon is visible is known as the full moon day.

  • The various shapes of the bright part of the moon as seen during a month are called phases of the moon.

  • On the fifteenth day the moon is not visible. This day is known as the new moon day.

  • The next day of the new moon day, only a small portion of the moon appears in the sky. This is known as the crescent moon.

  • The distance travelled by light in one year known as light year.

  • The stars forming a group that has a recognisable shape is called a constellation.

  • A body revolving around another body is called a satellite.

  • A planet has a definite path in which it revolves around the Sun. This path is called an orbit.

  • The movement of planets around the sun on their orbit is called revolution. 

  • The planets move on their own axis like top, Such movement s known as rotation. 

  • Mars appears slightly reddish and, therefore, it is also called the red planet.

  • Moon revolving round the Sun.

  • The smallest planet is mercury.

  • The mass of Jupiter is about 318 times that of our Earth.

  • On July 21, 1969 (Indian time) the American astronaut Neil Armstrong
    landed on the moon for the first time.

  • There is a large gap in between the orbits of Mars and Jupiter. This gap is occupied by a large number of small objects that revolve around the Sun. These are called asteroids.

  • However we may see a bright streaks of light falling in the sky. These are commonly known as shooting stars, although they are not stars. They are called meteors.

  • The Sun is nearly 150,000,000 kilometres (150 million km) away from
    the Earth.

  • The artificial satellites revolve around the Earth. They are much closer than the moon.

  • Venus is the brightest planet in the night sky.


Page 1 of 5


Chapter Contents: