Merrillville Community Planetarium
Bringing the Universe to the Merrillville Schools and Northwest Indiana

Astronomical Scintillation

Stars are extremely far away. Stars twinkle because their light travels through our atmosphere, hitting varying temperatures and densities that refract or bend the light. The scientific term for twinkling is astronomical scintillation.

Planets don’t appear to twinkle because their reflected sunlight only travels a short distance. Planets can appear to twinkle when low on the horizon, seen through more of Earth’s atmosphere.