Aurora Over Circle, Alaska
1.01.1997

Aurora can make spectacular sights. This particular aurora was photographed hovering over the town of Circle, Alaska. Although Aurora might first appear to be moonlit clouds, they only add light to the sky, and hence can not block background stars from view.

The Milky Way Near the Southern Cross
3.05.1996

This breathtaking patch of sky would be above you were you to stand at the south pole of the Earth. Just above and to the right of the photograph's center are the four stars that mark the boundaries of the famous Southern Cross.

The Same Color Illusion
7.10.2012

Are square A and B the same color? They are! To verify this, either run your cursor over the image or click here to see them connected. The above illusion, called the same color illusion, illustrates that purely human observations in science may be ambiguous or inaccurate.

Serene Paraselene
2.04.2010

Nestled in the Austrian Alps, frozen Lake Ossiach stretches across the foreground of this serene view. Recorded on March 1, the night sky includes a nearly full Moon and bright planet Saturn seen through thin clouds near picture center. It also includes a remarkably bright and colorful moondog or paraselene at the left.

The Gum Nebula Supernova Remnant
20.04.2003

Because the Gum Nebula is the closest supernova remnant, it is actually hard to see. Spanning 40 degrees across the sky, the nebula is so large and faint it is easily lost in the din of a bright and complex background.

Night on a Spooky Planet
29.10.2017

What spooky planet is this? Planet Earth of course, on a dark and stormy night in 2013 at Hverir, a geothermally active area along the volcanic landscape in northeastern Iceland. Geomagnetic storms produced...

A Lenticular Cloud Over Wyoming
26.03.2003

Is that a cloud or a flying saucer? Both, although it is surely not an alien spacecraft. Lenticular clouds can be shaped like a saucer, and can fly in the sense that, like most clouds, they are composed of small water droplets that float on air.

A Dark and Stormy Night
31.10.2003

It was a dark and stormy night. But on August 29th the red planet Mars, near it's closest approach to Earth in almost 60,000 years, shone brightly in the sky against a background of stars in the constellation Aquarius.

Shapley 1: An Annular Planetary Nebula
12.12.1995

This strange structure is what can result when a normal star runs out of nuclear fuel in its core. At that time, the center condenses into a white dwarf while the outer atmospheric layers are expelled into space and appear as a planetary nebula.

The Pleiades Star Cluster
1.12.2002

It is the most famous star cluster on the sky. The Pleiades can be seen without binoculars from even the depths of a light-polluted city. Also known as the Seven Sisters and M45, the Pleiades is one of the brightest and closest open clusters.