Question

explain why the planets do not Twinkle but Stars Twinkle.

Answer 1

we know that stars are a point sized sources of light and hence the light from them is retracted in the atmosphere, resulting is twinkling whereas the planets are a group of sources of light and hence the refraction of all the light rays coming from the the planets cancel out and results in a continuous flow of light and no twinkling.

Answer 2

the planets are much closer to the earth and are thus seen as extended source . if we consider a planet as a collection of a large number of points sized source of light the total variation in the amount of light entering our eye from all the individual point sized do will average out of zero , therefore nullifying the twinkling effect.