Solstice Celebration
21.12.2002

Aloha and Season's greetings! On December 22nd, at 01:14 Universal Time (December 21, 3:14pm Hawaii-Aleutian Standard Time), the Sun reaches its southernmost point in planet Earth's sky marking the final season change for the year 2002. In celebration, consider this delightfully detailed, brightly colored image of the active Sun.

A Sharper View of a Tilted Planet
18.11.2004

These sharp views of tilted gas giant Uranus show dramatic details of the planet's atmosphere and ring system. The remarkable ground-based images were made using a near-infrared camera and the Keck Adaptive Optics system to reduce the blurring effects of Earth's atmosphere.

The Tadpoles of IC 410
11.01.2006

This close-up view shows a portion of otherwise faint emission nebula IC 410 in striking false-colors. It also shows two remarkable denizens of the glowing gas cloud at the right - the "tadpoles" of IC 410. The picture is a composite of images taken through narrow band filters intended to trace atoms in the nebula.

Trio Leo
9.03.2006

This popular group is famous as the Leo Triplet - a gathering of three magnificent galaxies in one field of view. Crowd pleasers when imaged with even modest telescopes, these galaxies can be introduced individually as NGC 3628 (top), M66 (bottom left), and M65 (bottom right). All three are large spiral galaxies.

100 Hours of Astronomy Begins
2.04.2009

Today, 100 Hours of Astronomy begins, a cornerstone project of the International Year of Astronomy 2009 celebrating the 400th anniversary of Gallileo's original telescopic exploration of the sky. Running from April 2 through...

A Green Flash from the Sun
4.01.2011

Many think it is just a myth. Others think it is true but its cause isn't known. Adventurers pride themselves on having seen it. It's a green flash from the Sun. The truth is the green flash does exist and its cause is well understood.

APOD: 2024 October 6 Б The Magnificent Tail of Comet McNaught
6.10.2024

Comet McNaught, the Great Comet of 2007, grew a spectacularly long and filamentary tail. The magnificent tail spread across the sky and was visible for several days to Southern Hemisphere observers just after sunset. The amazing ion tail showed its greatest extent on long-duration, wide-angle camera exposures.

APOD: 2025 January 8 Б Supernova Remnants Big and Small
8.01.2025

What happens after a star explodes? A huge fireball of hot gas shoots out in all directions. When this gas slams into the existing interstellar medium, it heats up so much it glows. Two different supernova remnants (SNRs) are visible in the featured image, taken at the Oukaцmeden Observatory in Morocco.

Comet Kudo-Fujikawa: Days in the Sun
30.01.2003

Cruising through the inner Solar System, new Comet Kudo-Fujikawa reached perihelion, its closest approach to the Sun, yesterday, January 29. Passing within 28.4 million kilometers of the Sun, this comet came much closer than innermost planet Mercury basking only 57.9 million kilometers from our parent star.

The Swarm
29.07.2006

What do you call a group of black holes ... a flock, a brace, a swarm? Monitoring a region around the center of our Galaxy, astronomers have indeed found evidence for a surprisingly large number...