Question

what is meant by scattering?how twinkling of stars happen?

Answer 1

twinkling of stars happen because when the special lights departed from stars fall on our atmosphere some of the light scatter while some light become visible. this rapid visibility and non visibility of light of a star causes twinkling.

Answer 2

Scattering means spreading. Disturbance in the atmosphere makes a star to twinkle. It is so because there are many gases in the atmosphere.
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