A Picturesque Venus Transit
16.10.2011

The rare transit of Venus across the face of the Sun in 2004 was one of the better-photographed events in sky history. Both scientific and artistic images flooded in from the areas that could see the transit: Europe and much of Asia, Africa, and North America.

A Hole Punch Cloud Over Alabama
11.01.2004

What could create a huge hole the clouds? Such a hole, likely hundreds of meters across, was photographed last month from a driveway near Mobile, Alabama, USA. Very unusual to see, hole-punch clouds like this are still the topic of meteorological speculation. A leading hypothesis holds that the hole-punch cloud is caused by falling ice-crystals.

Andromeda before Photoshop
13.10.2019

What does the Andromeda galaxy really look like? The featured image shows how our Milky Way Galaxy's closest major galactic neighbor really appears in a long exposure through Earth's busy skies and with a digital camera that introduces normal imperfections.

Clouds and Stars over Cotopaxi Volcano in Ecuador
26.05.2010

What's happening above the Cotopaxi volcano in Ecuador? Quite a bit, from the looks of the above one-night, time-lapse movie, taken earlier this month. The majestic volcano is first seen through breaks in fast moving clouds as the movie begins.

Shuttle Reentry Streak from Orbit
1.08.2011

What's that strange bright streak? It is the last image ever of a space shuttle from orbit. A week and a half ago, after decoupling from the International Space Station, the Space Shuttle Atlantis fired its rockets for the last time, lost its orbital speed, and plummeted back to Earth.

Airglow Over Germany
5.09.2012

Does air glow? It does, but it is usually hard to see. When conditions are right, however, a faint glow about 90 kilometers up can be observed, most easily with a wide-angle long-duration camera exposure.

A Picturesque Venus Transit
23.06.2004

The rare transit of Venus across the face of the Sun earlier this month was one of the better-photographed events in sky history. Both scientific and artistic images have been flooding in from the areas that could see the transit: Europe and much of Asia, Africa, and North America.

A Sonic Boom
20.02.2001

Many people have heard a sonic boom, but few have seen one. When an airplane travels at a speed faster than sound, density waves of sound emitted by the plane cannot precede the plane, and so accumulate in a cone behind the plane.

Fly Me to the Moon
16.01.2017

No, this is not a good way to get to the Moon. What is pictured is a chance superposition of an airplane and the Moon. The contrail would normally appear white, but the large volume of air toward the setting Sun preferentially knocks away blue light, giving the reflected trail a bright red hue.

APOD: 2024 October 13 Б Aurora Timelapse Over Italian Alps
12.10.2024

Did you see last night's aurora? This question was relevant around much of the world a few days ago because a powerful auroral storm became visible unusually far from the Earth's poles.