APOD: 2023 December 4 Б Plane Crossing Crescent Moon
4.12.2023

No, the Moon is not a bow, and no, it did not shoot out a plane like an arrow. What is pictured is a chance superposition. The plane's contrail would normally appear white...

The Moona Lisa
14.09.2024

Only natural colors of the Moon in planet Earth's sky appear in this creative visual presentation. Arranged as pixels in a framed image, the lunar disks were photographed at different times. Their varying hues are ultimately due to reflected sunlight affected by changing atmospheric conditions and the alignment geometry of Moon, Earth, and Sun.

GRO J1655 40: Evidence for a Spinning Black Hole
8.05.2001

In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole. Studies of the bright light emitted by the swirling gas frequently indicate not only that a black hole is present, but also likely attributes.

Giant Emission Nebula NGC 3603 in Infrared
14.08.2002

NGC 3603 is the largest region of glowing gas in our Milky Way galaxy. Spanning over 20 light years across, the giant emission nebula (HII region) is home to a massive star cluster, thick dust pillars, and a star about to explode.

Hale-Bopp Brightest Comet This Decade
13.03.1997

The Great Comet of 1997 is now brighter than the Great Comet of 1996 ever was. In fact, it is brighter than almost every star in the sky. Yet Comet Hale-Bopp is still about two weeks away from maximum light.

Old Faithful Meets Hale-Bopp
26.05.1997

As Comet Hale-Bopp leaves our Northern Skies, it provides us with yet another burst of joy. On May 11th the fading comet was photographed behind the famous "Old Faithful" water geyser of Yellowstone National Park, Wyoming, USA, Planet Earth.

Vega
15.07.1997

Vega is a bright blue star 25 light years away. Vega is the brightest star in the Summer Triangle, a group of stars easily visible summer evenings in the northern hemisphere. The name Vega...

Bright Comet SOHO
21.05.1998

Discovered this month with an orbiting solar observatory, bright Comet SOHO has now emerged from the Sun's glare. This telephoto picture of the new naked-eye comet was taken by astrophotographer Michael Horn after sunset in the western twilight above Lake Samsonvale, Brisbane, Australia on May 18. The comet is seen in the constellation Orion.

A Western Sky at Twilight
1.05.2004

On April 23rd, the Moon along with planets Saturn, Mars, and Venus (and planet Earth of course ...) were all visible in the west at twilight, captured here from a site near Saylorvillle Lake north of Des Moines, Iowa, USA.

Noctilucent Clouds Over Sweden
18.07.2006

Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above.