eli5 Why does light around stars flicker when you look at them in the night sky?

Question

eli5 Why does light around stars flicker when you look at them in the night sky?

In: Physics

Answer 1

Atmospheric shimmer.

The atmosphere isn’t static, and isn’t *perfectly* transparent. Different densities, wind currents, small dust particles, etc etc all add up to make light shift around slightly as it passes through.

This is why space telescopes are so useful, it eliminates this concern