Why Stars Twinkle: Atmospheric Effects on Light

Stars twinkle because their light is bent by Earth’s turbulent atmosphere.
As air pockets of varying temperatures move, they refract starlight in shifting directions.
This constant bending makes stars appear to flicker, change color, or even dance.
Planets usually don’t twinkle as much because their disks spread the light more evenly.
The effect is strongest near the horizon, where starlight travels through more atmosphere.
Astronomers call this flickering “stellar scintillation.”
Telescopes with adaptive optics can correct for twinkling, producing sharper images.
High-altitude observatories and space telescopes avoid most of the twinkle problem.
Ancient sky-watchers often used twinkling as a sign to predict weather changes.
Without the atmosphere, stars in space shine steady and crystal clear.