If you look at the night sky you will see all the stars twinkle. TRUE! That is what you see. However it is nothing to do with the Star but with our atmosphere…..the atmosphere is always moving and there are lots of regions with different temperatures and different densities. The light coming from that tiny point (in angular terms) in space, gets bent around or "refracted" (see "HEAT RISES") so the intensity of the light at your eye keeps changing. If you were on the Moon where there is NO AIR the stars would not twinkle at all but would keep a constant brightness. That is why the Hubble Space telescope gets such wonderful pictures because it is outside our atmosphere.
For least twinkle….go to a place where the air is least dense and a reasonably constant temperature (and no pollution)…that is why many space telescopes are on mountains in Hawaii.
Incidentally, the way to tell the difference between a planet and a star in the night sky is that planets do NOT twinkle..the reason for this is that they are bigger objects in the sky to us than a distant star so a "thicker beam" of light reaches us and the refraction has very little effect on the intensity which reaches the eye.

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