APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.


A Lunar Corona with Jupiter and Saturn
Explanation: Why does a cloudy moon sometimes appear colorful? The effect , called a lunar corona , is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud. Since light of different colors has different wavelengths , each color diffracts differently. Lunar Coronae are one of the few quantum mechanical color effects that can be easily seen with the unaided eye. Solar corona e are also sometimes evident. The featured composite image was captured a few days before the close Great Conjunction between Saturn and Jupiter last month . In the foreground, the Italian village of Pieve di Cadore is visible in front of the Sfornioi Mountains.
New: APOD is now available in Taiwanese from National Central University
| Date | January 19, 2021 |
|---|---|
| Credit | Image Credit & Copyright: Alessandra Masi |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |


