3D Mars: Northern Terra Meridiani
28.08.2002

In this spectacular 3D stereoscopic view from orbit, steep-sided, flat-topped hills stand above the Terra Meridiani region of Mars. Seen best with red/blue glasses (red for the left eye), the structures are reminiscent of buttes and mesas found in southwestern areas of the North American continent on planet Earth.

Gibbous Europa
2.12.2007

Although the phase of this moon might appear familiar, the moon itself might not. In fact, this gibbous phase shows part of Jupiter's moon Europa. The robot spacecraft Galileo captured this image mosaic during its mission orbiting Jupiter from 1995 - 2003.

Where is Upsilon Andromedae
22.04.1999

Astronomers recently announced the detection of three large planets orbiting the star Upsilon Andromedae - the first planetary system known to orbit a normal star other than our Sun. These planets were not directly photographed but found through a Doppler technique developed to use large telescopes to search nearby stars for wobbling planetary signatures.

Zodiacal Light and the False Dawn
25.09.2007

An unusual triangle of light will be particularly bright near the eastern horizon before sunrise during the next two months for observers in Earth's northern hemisphere. Once considered a false dawn, this triangle of light is actually Zodiacal Light, light reflected from interplanetary dust particles.

APOD: 2025 February 5 Б Comet G3 ATLAS Setting over a Chilean Hill
5.02.2025

Where is Comet ATLAS going? In the featured time-lapse video, the comet is not itself moving very much, but the Earth's rotation makes it appear to be setting over a hill. The Comet C/2024 G3 (ATLAS) sequence was captured with an ordinary camera on January 22 from the Araucanцa Region in central Chile.

Cooling Neutron Star
1.05.2017

The bright source near the center is a neutron star, the incredibly dense, collapsed remains of a massive stellar core. Surrounding it is supernova remnant Cassiopeia A (Cas A), a comfortable 11,000 light-years away. Light from the Cas A supernova, the death explosion of a massive star, first reached Earth about 350 years ago.

The Cosmic X-Ray Background
9.11.2000

Early on, x-ray satellites revealed a surprising cosmic background glow of x-rays and astronomers have struggled to understand its origin. Now, peering through a hole in the obscuring gas and dust...

Galaxy Formation in a Magnetic Universe
19.02.2018

How did we get here? We know that we live on a planet orbiting a star orbiting a galaxy, but how did all of this form? To understand details better, astrophysicists upgraded the famous Illustris Simulation into IllustrisTNG -- now the most sophisticated computer model of how galaxies evolved in our universe.

A Magellanic Mural
3.02.1998

Two galaxies stand out to casual observers in Earth's Southern Hemisphere: the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC). These irregular galaxies are two of the closest galaxies to our Milky Way Galaxy.

Comet Meets Moon and Morning Star
12.12.2015

A crescent Moon and brilliant Venus met in predawn skies on December 7, a beautiful conjunction of planet Earth's two brightest celestial beacons after the Sun. Harder to see but also on the scene was Comet Catalina (C/2013 US10).