Why Do Stars Twinkle?

Why do stars twinkle? It’s a similar effect to why a hot road looks shimmery. The turbulent atmosphere refracts the incoming starlight to different degrees so the “beam” of light reaching your eye becomes randomly distorted but deviates only minutely from its path, just enough so that it looks like the star is twinkling. It’s the bane of ground-based astronomers and is part of the reason we sent up the Hubble space telescope. However, there are techniques that can overcome twinkle.

Twinkle no more Little Star

A laser optics system can produce a guide star anywhere in the night sky of the southern hemisphere, thanks to work by scientists at Cerro Paranal in Chile, home of the ESO Very Large Telescope array. The star allows astronomers to apply adaptive optics systems to their telescopes effectively cancelling out atmospheric disturbances, better known as a star’s twinkle!

Read the latest on detwinkling in the Spotlight Newsletter