Question

To an observer on earth the stars appear to twinkle this can be described to

Answer 1

The the twinkling of stars is due to the atmospheric refraction of starlight. the starlight on entering the earth atmosphere undergoes refraction continuously before it reaches the earth. Since the atmosphere bend starlights towards normal the Apparent position of star light different from its actual position the Apparent position of star keeps on changing due to wind and convention currents fluctuating image of the star makes them appear twinkling to the observer