Iridescent Clouds over Thamserku
8.07.2014

Why would a cloud appear to be different colors? A relatively rare phenomenon known as iridescent clouds can show unusual colors vividly or a whole spectrum of colors simultaneously. These clouds are formed of small water droplets of nearly uniform size.

A Lunar Corona over Turin
16.09.2019

What are those colorful rings around the Moon? A corona. Rings like this will sometimes appear when the Moon is seen through thin clouds. The effect is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud.

Nebulosity in Sagittarius
18.07.1996

What causes the colors in this beautiful nebulosity in Sagittarius? Dubbed NGC 6589 and NGC 6590, the colors of this nebulosity, are caused by gas and dust. The blue color of the nebula nearest the bright stars is caused by reflection off interstellar dust.

Rainbow Perseid
16.08.2002

While meteors do show colors, the colors aren't always seen with the unaided eye. Still, high speed color film recorded this rainbow-like trail as a meteor streaked through the early morning sky on August 13 above Sedona, Arizona, USA.

As Above, So Below
3.12.2011

A single, long exposure captured these star trails above a remarkably colorful sea of clouds. As seen from Medvednica mountain, the surrounding peaks and lights illuminating the clouds from below are north of Zagreb, Croatia.

The Reddening of M71
9.12.2014

Now known to be a globular star cluster at the tender age of 10 billion years, M71 is a mere 13,000 light-years away within the narrow boundaries of the faint constellation Sagitta. Close...

APOD: 2025 October 5 Б A Long Storm System on Saturn
5.10.2025

It was one of the largest and longest lived storms ever recorded in our Solar System. First seen in late 2010, the featured cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet.

A Lunar Corona with Jupiter and Saturn
19.01.2021

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.

The Solar Spectrum
29.06.2003

It is still not known why the Sun's light is missing some colors. Shown above are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device.

A Rainbow Geminid Meteor
19.12.2018

Meteors can be colorful. While the human eye usually cannot discern many colors, cameras often can. Pictured is a Geminid captured by camera during last week's meteor shower that was not only impressively bright, but colorful.