Why do stars twinkle?

Why do stars twinkle?

Professor Gizmo (Amazing Science Presentations) gives expert video advice on: Why do we need to wear a space suit in space?; Why do things float around in space?; Why do stars twinkle? and more...

The twinkling of the stars is mainly caused by the light travelling such a long distance. When it finally reaches the Earth, and this could take years and years to reach. But, when it finally reaches the Earth it has to pass through the atmosphere. The atmosphere has dust and particles in it, and sometimes the light takes on a little bit of an optical illusion and it gives this off and on effect and so the stars appear to twinkle. Objects that are closer in the sky, like the moon and some of the other planets, they do not appear to twinkle because that light is not travelling as far as a star's light would travel.