M13: The Great Globular Cluster in Hercules
19.08.1998

M13 is one of the most prominent and best known globular clusters. Visible with binoculars in the constellation of Hercules, M13 is frequently one of the first steps beyond the ordinary visible to the casual sky gazer.

M104: The Sombrero Galaxy
15.08.1999

What's going on in the center of this spiral galaxy? Named the Sombrero Galaxy for its hat-like resemblance, M104 features a prominent dust lane and a bright halo of stars and globular clusters.

A Sun Pillar
29.12.2002

Have you ever seen a sun pillar? When the air is cold and the Sun is rising or setting, falling ice crystals can reflect sunlight and create an unusual column of light. Ice sometimes forms flat, stop-sign shaped crystals as it falls from high-level clouds.

APOD: 2008 January 1- Rays from an Unexpected Aurora
31.12.2007

This aurora was a bit of a surprise. For starters, on this day in 2002, no intense auroral activity was expected at all. Possibly more surprising, however, the aurora appeared to show an usual structure of green rays from some locations.

APOD: 2004 August 24- Supply Ship Approaches the Space Station
24.08.2004

The crew on board the International Space Station sometimes needs supplies. As the US Space Shuttle fleet prepares to return to flight, supplies usually now come from a robot Progress supply vessel launched from Kazakhstan.

NGC 869 and NGC 884: A Double Open Cluster
11.10.2005

Most star clusters are singularly impressive. Open clusters NGC 869 and NGC 884, however, are doubly impressive. Also known as "h and chi Persei", this unusual double cluster, shown above, is bright enough to be seen from a dark location without even binoculars.

Walking in Space
15.06.1996

Pictured above is the first american astronaut to walk in space: Edward White. White is seen floating outside the Gemini 4 capsule in 1965. The term "spacewalk" is deceiving since astronauts do not actually walk - they float - usually without their feet touching anything solid. White was connected to the spaceship only by a thick tether.

A String Of Pearls
22.03.1997

Comet Shoemaker-Levy 9, named after its co-discoverers, was often referred to as the "string of pearls" comet. It is famous for its unusual appearance as well as its collision with the planet Jupiter!

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.

M104: The Sombrero Galaxy
7.02.1997

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.