Question

Twinkling of stars is on account of
1. large distance of stars and storms in air.
2. rotation of earth
3. large size of stars
4. large distance of stars and fluctuations in the density of air.
5. None of the above/More than one of the above

Answer 1

Correct Answer - Option 4 : large distance of stars and fluctuations in the density of air.

The correct answer is option 4.

• To solve this type of question we must first know the basic concept of the twinkling of stars and then will see the options.
• Concept
  • Atmospheric refraction of starlight is responsible for the twinkling of stars.
• Explanation
  • The atmosphere has to change density layers hence when light rays cross the atmosphere, refraction of light rays occurs. 
  • Hence the eye sometimes receives more light with the result that the star appears brighter and sometimes it receives only a few rays or no rays which make the star appear fainter.
  • This continuous brighter and fainter appearance is known as the twinkling of the stars.
  • Hence, the twinkling of stars is on account of two major factors-
    • Large distance of stars.
    • Fluctuations in the density of the air.