Question

why does star Twinkle

Answer 1

The actual Star does not twinkle. It looks like twinkling because it is billions of kilometres away from us and are large heavenly bodies which give us light.

HOPE IT HELPS ^_^

Answer 2

The reason why stars twinkle is 'refraction of light'. The light from the stars gets refracted multiple times before reaching us due to the different densities of the atmospheric layers, giving the illusion of twinkling stars.