Why do stars appear to twinkle?. Physics & Astronomy

Stars twinkle when we see them from the Earth’s surface because we are viewing them through thick layers of urbulent air in the Earth’s atmosphere. As light travels through the many layers of the Earth’s atmosphere, the light of the star is bent (refracted) many times and in random directions. This random refraction results in the star winking out (it looks as though the star moves a bit, and our eye interprets this as twinkling)