Explain why the planets do not twinkle.
Stars are very far away from us and appear point sized to us
So, it appears that light is coming from one point source
Due to refraction of light from this point source, stars appear to twinkle
The planets are at a lesser distance from us as compared to the stars.
Since the planets are closer to us, they appear much bigger and the light appears to come from more than one point.
Dimming effect of some of the points of light coming from planet is nullified by brightening effect of light coming from other points.
Hence, planets do not twinkle.