The Great Wall by Moonlight
12.03.2015

Last Friday, an almost Full Moon rose as the Sun set, over this mountainous landscape north of Beijing, China. Also near apogee, the farthest point in its elliptical orbit around planet Earth, it was this year's smallest and faintest Full Moon.

Dragon Aurora over Norway
10.04.2018

What's that in the sky? An aurora. A large coronal hole opened last month, a few days before this image was taken, throwing a cloud of fast moving electrons, protons, and ions toward the Earth.

The Reappearance of Mars
11.09.2020

Mars reappears just beyond the Moon's dark limb in this stack of sharp video frames captured on September 6. Of course to reappear it had to disappear in the first place.

A Fire Rainbow over West Virginia
30.08.2021

What's happening to this cloud? Ice crystals in a distant cirrus cloud are acting like little floating prisms. Known informally as a fire rainbow for its flame-like appearance, a circumhorizon arc appears parallel to the horizon.

Lunation
18.02.2001

Our Moon's appearance changes nightly. This slow-loading time-lapse sequence shows what our Moon looks like during a lunation, a complete lunar cycle. As the Moon orbits the Earth, the half illuminated by the Sun first becomes increasingly visible, then decreasingly visible. The Moon always keeps the same face toward the Earth.

Uranus: The Tilted Planet
26.08.2001

Uranus is the third largest planet in our Solar System after Jupiter and Saturn. Uranus is composed mostly of rock and ices, but with a thick hydrogen and helium atmosphere. The blue hue of Uranus' atmosphere arises from the small amount of methane which preferentially absorbs red light.

Comet LINEAR WM1 Shines in the South
4.02.2002

A new comet has brightened unexpectedly and is currently visible to unaided observers of southern skies. Comet C/2000 WM1 (LINEAR) is now reported by some observers to be at third magnitude, making it brighter -- although more diffuse -- than most visible stars. A dust tail as long as 3 degrees has also been reported.

Globular Cluster M5
19.10.1995

The globular cluster M5, pictured above, contains roughly 100,000 stars. These stars formed together and are gravitationally bound. Stars orbit the center of the cluster, and the cluster orbits the center of our Galaxy. So far, about 160 globular clusters are known to exist in a roughly spherical halo around the Galactic center.

Apollo Sunrise
20.06.1996

In November of 1969, homeward bound aboard the "Yankee Clipper" command module, the Apollo 12 astronauts took this dramatic photograph of the Sun emerging from behind the Earth. From this distant perspective, part...

Aurora Astern
30.11.1996

Sailing upside down, 115 nautical miles above Earth, the crew of the Space Shuttle Endeavour made this spectacular time exposure of the southern aurora (aurora australis) in October of 1994. The aurora, also known...