Explain why the planets do not twinkle?

Explanation

Planets are much closer to the earth and are seen as extended sources. So, a planet may be considered as a collection of a large number of point-sized light source3s . Although light coming from individual point -sezed sources flickers but the total amount of light entering our eye from all the individual point-sized sources avereage out the to be constant. Thereby planets appear equally bright and there is no twinkling of plantes.