Spiral Galaxies in Collision
9.11.1999

Billions of years from now, only one of these two galaxies will remain. Until then, spiral galaxies NGC 2207 and IC 2163 will slowly pull each other apart, creating tides of matter, sheets of shocked gas, lanes of dark dust, bursts of star formation, and streams of cast-away stars.

The Surface of Titan
4.08.1999

If sailing the hydrocarbon seas of Titan, beware of gasoline rain. Such might be a travel advisory issued next millennium for adventurers visiting Titan, the largest moon of Saturn. Images of Titan's surface were released last week from the Keck 10-meter telescope featuring the finest details yet resolved.

Shadow of a Martian Robot
29.06.2008

What if you saw your shadow on Mars and it wasn't human? Then you might be the Opportunity rover currently exploring Mars. Opportunity and sister robot Spirit have been probing the red planet since early 2004, finding evidence of ancient water, and sending breathtaking images across the inner Solar System.

Comet Between Fireworks and Lightning
10.11.2013

Sometimes the sky itself is the best show in town. In January 2007, people from Perth, Australia gathered on a local beach to watch a sky light up with delights near and far. Nearby, fireworks exploded as part of Australia Day celebrations. On the far right, lightning from a thunderstorm flashed in the distance.

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...

Aurora Georgia
16.05.2024

A familiar sight from Georgia, USA, the Moon sets near the western horizon in this rural night skyscape. Captured on May 10 before local midnight, the image overexposes the Moon's bright waning crescent at left in the frame. A long irrigation rig stretches across farmland about 15 miles north of the city of Bainbridge.

The Milky Way in Infrared
29.12.1997

At night, from a dark location, part of the clear sky looks milky. This unusual swath of dim light is generally visible during any month and from any location. Until the invention of the telescope, nobody really knew what the "Milky Way" was.

The Regolith of Asteroid Eros
29.08.2000

From fifty kilometers above asteroid Eros, the surface inside one of its largest craters appears covered with an unusual substance: regolith. The thickness and composition of the surface dust that is regolith remains a topic of much research.

Comet McNaught Over New Zealand
12.02.2007

Comet McNaught is perhaps the most photogenic comet of our time. After making quite a show in the northern hemisphere in mid January, the comet moved south and developed a long and unusual dust tail that dazzled southern hemisphere observers starting in late January.

Tethys Behind Titan
27.01.2010

What's that behind Titan? It's another of Saturn's moons: Tethys. The robotic Cassini spacecraft orbiting Saturn captured the heavily cratered Tethys slipping behind Saturn's atmosphere-shrouded Titan late last year. The largest crater on Tethys, Odysseus, is easily visible on the distant moon.