Jumping Sundogs Over Thunderclouds
8.11.2011

What's happening above those clouds? In the past few years, videos have appeared on the web detailing an unusual but little known phenomenon: rapid light changes over clouds. Upon inspection and contemplation, a leading hypothesis for its cause has now emerged.

Pillar at Sunset
6.03.2010

Reddened light from the setting Sun illuminates the cloud banks hugging this snowy, rugged terrain. Inspiring a moment of quiet contemplation, the sunset scene included a remarkable pillar of light that seemed to connect the clouds in the sky with the mountains below.

A Full Moon at Perigee
8.11.2025

What is big, bright, and beautiful, can wear a cape made of clouds, and is at the closest point in its elliptical orbit around planet Earth? A full moon at perigee of course, captured here near moonset in predawn skies on November 5 from Kayseri, Turkiye.

Local Group Galaxy NGC 205
8.01.1996

The Milky Way Galaxy is not alone. It is part of a gathering of about 25 galaxies known as the Local Group. Members include the Great Andromeda Galaxy (M31), M32, M33, the Large Magellanic Clouds, the Small Magellanic Clouds, Dwingeloo 1, several small irregular galaxies, and many dwarf elliptical galaxies.

Diamond Ring and Shadow Bands
24.07.2010

As the total phase of July 11's solar eclipse came to an end, sunlight streaming past the edge of the Moon's silhouette created the fleeting appearance of a glistening diamond ring in the sky.

APOD: 2026 May 19 Б NGC 2170: The Angel Nebula
19.05.2026

Is this a painting or a photograph? In this celestial abstract art composed with a cosmic brush, dusty nebula NGC 2170, also known as the Angel Nebula, shines just above the image center. Reflecting...

M16: Infrared Star Hunt
4.01.2002

The head of an interstellar gas and dust cloud is shown here in false-color, a near-infrared view recorded by astronomers hunting for stars within M16's Eagle Nebula. Made famous in a 1995 Hubble...

Perijove 16: Passing Jupiter
5.02.2019

Watch Juno zoom past Jupiter again. NASA's robotic spacecraft Juno is continuing on its 53-day, highly-elongated orbits around our Solar System's largest planet. The featured video is from perijove 16, the sixteenth time that Juno has passed near Jupiter since it arrived in mid-2016.

Pauli Exclusion Principle: Why You Don't Implode
19.02.2003

Why doesn't matter just bunch up? The same principle that keeps neutron stars and white dwarf stars from imploding also keeps people from imploding and makes normal matter mostly empty space. The observed reason is known as the Pauli Exclusion Principle.

APOD: 2025 July 27 Б Lightning over the Volcano of Water
27.07.2025

Have you ever watched a lightning storm in awe? You're not alone. Details of what causes lightning are still being researched, but it is known that inside some clouds, internal updrafts cause collisions between ice and snow that slowly separate charges between cloud tops and bottoms.