Question

" Twinkling of star occurs due to change in the earth's atmosphere." Does this "CHANGE" refer to change in various atmospheric level i.e. mesosphere, thermosphere or does it mean that it occurs due to movement of air etc.

Answer 1

Twinkling of the star is caused due to a phenomena called Refraction of light. When ray of light travel from one medium to another medium it bend toward/away the normal.Many factor affect Refraction of light such as Temperature,Movement of air,etc.The ray of light coming from the star (point source since due to a large distance)when enter in the atmosphere it bend toward the normal.it is due to different layer not levels.So apparent position and original position is different