The Horsehead Nebula
31.12.2013

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula in the center of the above photograph. The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright red emission nebula.

Total Lunar Eclipse from Sydney
28.05.2021

The reddened shadow of planet Earth plays across the lunar disk in this telescopic image taken on May 26 near Sydney, New South Wales, Australia. On that crisp, clear autumn night a Perigee Full Moon slid through the northern edge of the shadow's dark central umbra.

APOD: 2024 January 14 Б Dragon Aurora over Iceland
14.01.2024

Have you ever seen a dragon in the sky? Although real flying dragons don't exist, a huge dragon-shaped aurora developed in the sky over Iceland in 2019. The aurora was caused...

Uranus' Ring System
30.04.1996

The rings of Uranus are thin, narrow, and dark compared to other planetary ring systems. Brightened artificially by computer, the ring particles reflect as little light as charcoal, although they are really made of ice chucks darkened by rock.

Storm Clouds Over Jupiter
27.11.1996

Storm clouds, similar to the familiar cumulonimbus thunderheads of Earth, appear to be present on Jupiter. The mosaic of images above shows the region near the raging edge of Jupiter's Great Red Spot, itself some 2 to 3 Earths wide, as observed by the Galileo spacecraft in June of this year.

The Surface of Titan
20.08.2000

If sailing the hydrocarbon seas of Titan, beware of gasoline rain. Such might be a travel advisory issued one future day for adventurers visiting Titan, the largest moon of Saturn. New images of Titan's surface were released last week from the Canada-France Hawaii Telescope featuring the finest details yet resolved.

Orions Horsehead Nebula
29.01.2003

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula seen above and to the right of center in the above photograph. The bright star on the left is located in the belt of the familiar constellation of Orion.

A Chicago Meteorite Fall
6.05.2003

If you wait long enough, a piece of outer space itself will come right to you. As Colby Navarro worked innocently on the computer, a rock from space crashed through the roof, struck the printer, banged off the wall, and came to rest near the filing cabinet.

A Wolf-Rayet Star Blows Bubbles
3.01.1997

Wolf-Rayet stars can blow bubbles. These unusual stars are much hotter and more luminous than our Sun. All extremely massive stars will eventually evolve though a Wolf-Rayet phase. Approximately 200 Wolf-Rayet stars are known in our Milky Way Galaxy. Wolf-Rayet stars generate bubbles because they continually eject their outer atmosphere as a stellar wind.

Shadow Rise
22.08.2003

As the Sun sets, the Earth's shadow rises up from the east. The subtle beauty of this daily apparition is often overlooked in favor of the brighter, more colorful western horizon. But while...