Introducing Comet Lee
27.04.1999

Another large snowball is falling toward the Sun. Comet Lee was discovered two weeks ago by Steve Lee (AAO) in Australia, and is expected to brighten as it approaches the inner Solar System. Comet...

Crescent Neptune and Triton
27.05.2023

Gliding through the outer Solar System, in 1989 the Voyager 2 spacecraft looked toward the Sun to find this view of most distant planet Neptune and its moon Triton together in a crescent phase. The elegant image of ice-giant planet and largest moon was taken from behind just after Voyager's closest approach.

Looking Back on an Eclipsed Earth
26.09.2004

Here is what the Earth looks like during a solar eclipse. The shadow of the Moon can be seen darkening part of Earth. This shadow moved across the Earth at nearly 2000 kilometers per hour.

Big Sky Comet
21.04.1997

On April 17^th, "Big Sky" country sure lived up to its name. The dark skies over the US states of Wyoming, Montana and the Dakotas were quite busy, as shown by this photograph featuring Comet Hale-Bopp. In the foreground is the Absaroka Mountain Range in Wyoming, lit by reflected moonlight.

A Wolf Rayet Star Bubble
28.09.1997

What's a Wolf-Rayet star, and how did it create that spherical bubble and sweeping arc? A Wolf-Rayet star is a star that originated with a mass over 40 times that of our Sun.

Northern Green Flash
23.06.2012

As seen from Frösön island in northern Sweden the Sun did set a day after the summer solstice. From that location below the arctic circle it settled slowly behind the northern horizon.

A Wolf-Rayet Star Bubble
26.08.1996

What's a Wolf-Rayet star, and how did it create that spherical bubble and sweeping arc? A Wolf-Rayet star is a star that originated with a mass over 40 times that of our Sun.

M104: The Sombrero Galaxy
8.02.1997

The famous Sombrero galaxy (M104) is a bright nearby spiral galaxy. The prominent dust lane and halo of stars and globular clusters give this galaxy its name. Something very energetic is going on in the Sombrero's center, as much X-ray light has been detected from it.

Neptune: Big Blue Giant
21.02.1998

This picture was taken by the Voyager 2 spacecraft in 1989 - the only spacecraft ever to visit Neptune. Neptune will be the farthest planet from the Sun until 1999, when the elliptical orbit of Pluto will cause it to once again resume this status.

Dueling Auroras
7.08.2005

Will it be curtains for one of these auroras? A quick inspection indicates that it is curtains for both, as the designation "curtains" well categorizes the type of aurora pattern pictured. Another (informal) type is the corona.