Ash and Lightning above an Icelandic Volcano
12.05.2019

Why did a picturesque volcanic eruption in Iceland create so much ash? Although the large ash plume was not unparalleled in its abundance, its location was particularly noticeable because it drifted across such well-populated areas.

Planet Line over New York Bridge
20.04.2022

There's an interesting sky to see if you wake up before the Sun. Lined up on toward the eastern horizon are four planets in a row. The planets are so bright they can even be seen from the bright sky inside a city.

NGC 6334: The Cats Paw Nebula
10.05.2022

Nebulas are perhaps as famous for being identified with familiar shapes as perhaps cats are for getting into trouble. Still, no known cat could have created the vast Cat's Paw Nebula visible toward the constellation of the Scorpion (Scorpius.

The Mysterious Rings of Supernova 1987a
5.07.1996

What's causing those odd rings in supernova 1987a? In 1987, the brightest supernova in recent history occurred in the Large Magellanic Clouds. At the center of the picture is an object central to the remains of the violent stellar explosion.

Big Beautiful Saturn
25.12.2004

As a present to APOD readers, digital imager Mattias Malmer offers a very high resolution view of big beautiful Saturn. A labor of love, his full mosaic, composite image is contained in a large 5 megabyte jpeg file (preview here, download here) and spans the gorgeous gas giant from ring tip to ring tip.

Airglow Ripples over Tibet
1.09.2014

Why would the sky look like a giant target? Airglow. Following a giant thunderstorm over Bangladesh in late April, giant circular ripples of glowing air appeared over Tibet, China, as pictured above. The unusual...

Aurora and Volcanic Light Pillar
23.09.2014

That's no sunset. And that thin red line just above it -- that's not a sun pillar. The red glow on the horizon originates from a volcanic eruption, and the red line is the eruption's reflection from fluttering atmospheric ice crystals. This unusual volcanic light pillar was captured over Iceland earlier this month.

Astronaut Kicks Lunar Field Goal
1.04.2019

Score three points for NASA. With time running out late in Apollo 15's mission to the Moon in 1971, Astronaut David Scott prepared to split the uprights and bring about yet another dramatic end-of-the-mission victory for NASA. Scott used a special lunar football designed for the rugged games held on the Moon.

SuitSat1: A Spacesuit Floats Free
27.04.2014

A spacesuit floated away from the International Space Station eight years ago, but no investigation was conducted. Everyone knew that it pushed by the space station crew. Dubbed Suitsat-1, the unneeded Russian Orlan spacesuit filled mostly with old clothes was fitted with a faint radio transmitter and released to orbit the Earth.

M78 and Orion Dust Reflections
24.01.2017

In the vast Orion Molecular Cloud complex, several bright blue nebulas are particularly apparent. Pictured here are two of the most prominent reflection nebulas - dust clouds lit by the reflecting light of bright embedded stars. The more famous nebula is M78, in the image center, cataloged over 200 years ago.