Rainbows and Rays over Bryce Canyon
28.07.2015

What's happening over Bryce Canyon? Two different optical effects that were captured in one image taken earlier this month. Both effects needed to have the Sun situated directly behind the photographer. The nearest...

Lucid Dreaming
4.04.2016

Is this the real world? Or is it just fantasy? The truth started with a dream -- a dream that the spectacular Seljarlandsfoss waterfall in southern Iceland could be photographed with a backdrop of an aurora-filled sky. Soon after a promising space weather report, the visionary astrophotographer and his partner sprang into action.

Manicouagan Impact Crater from Space
25.05.2024

Orbiting 400 kilometers above Quebec, Canada, planet Earth, the International Space Station Expedition 59 crew captured this snapshot of the broad St. Lawrence River and curiously circular Lake Manicouagan on April 11. Right of center, the ring-shaped lake is a modern reservoir within the eroded remnant of an ancient 100 kilometer diameter impact crater.

Colorful Airglow Bands Surround Milky Way
6.03.2018

Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere.

APOD: 2025 August 25 Б The Meteor and the Star Cluster
25.08.2025

Sometimes even the sky surprises you. To see more stars and faint nebulosity in the Pleiades star cluster (M45), long exposures are made. Many times, less interesting items appear on the exposures that were not intended -- but later edited out.

Orionids Meteor Shower to Peak Tonight
21.10.1996

Tonight you might be able to see Halley's Comet again - or at least some pieces of it. It is widely thought that that the meteors from the Orionids meteor shower, which peaks tonight, are just small pieces of Halley's Comet falling to Earth.

Bright Cliffs Across Saturns Moon Dione
5.09.2006

What causes the bright streaks on Dione? Recent images of this unusual moon by the robot Cassini spacecraft now orbiting Saturn are helping to crack the mystery. Close inspection of Dione's trailing hemisphere, pictured above, indicates that the white wisps are composed of deep ice cliffs dropping hundreds of meters.

Aurora Over White Dome Geyser
17.10.2012

Sometimes both heaven and Earth erupt. Colorful aurorae erupted unexpectedly earlier this month, with green aurora appearing near the horizon and brilliant bands of red aurora blooming high overhead. A bright Moon lit the foreground of this picturesque scene, while familiar stars could be seen far in the distance.

APOD: 2025 January 19 Б Titan Touchdown: Huygens Descent Movie
19.01.2025

What would it look like to land on Saturn's moon Titan? The European Space Agency's Huygens probe set down on the Solar System's cloudiest moon in 2005, and a time-lapse video of its descent images was created.

Four Billion BCE: Battered Earth
5.08.2014

No place on Earth was safe. Four billion years ago, during the Hadean eon, our Solar System was a dangerous shooting gallery of large and dangerous rocks and ice chunks. Recent examination of lunar...