Why do stars twinkle? © Getty Images

What makes stars twinkle?

Twinkle, twinkle little star, refraction makes you what you are...

Asked by: Anonymous
Excluding the Sun, stars are located so far away that even through a telescope they appear as a single point of light. When you look up at a star, turbulence in the atmosphere refracts the light from coming from it in different directions. This makes the star appear to change brightness and position, which can make it look as if it’s twinkling.

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