Hickson 44 in Leo
29.08.2011

Scanning the skies for galaxies, Canadian astronomer Paul Hickson and colleagues identified some 100 compact groups of galaxies, now appropriately called Hickson Compact Groups. The four prominent galaxies seen in this intriguing telescopic skyscape are one such group, Hickson 44, about 100 million light-years distant toward the constellation Leo.

Across the Center of Centaurus A
29.11.2011

A fantastic jumble of young blue star clusters, gigantic glowing gas clouds, and imposing dark dust lanes surrounds the central region of the active galaxy Centaurus A. This image from the Hubble Space Telescope has been processed to present a natural color picture of this cosmic maelstrom.

Total Lunar Eclipse over Waterton Lake
27.09.2015

Recorded in 2014 April, this total lunar eclipse sequence looks south down icy Waterton Lake from the Waterton Lakes National Park in Alberta, Canada, planet Earth. The most distant horizon includes peaks in Glacier National Park, USA.

APOD: 2025 July 13 Б Planetary Nebula Mz3: The Ant Nebula
12.07.2025

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

The Bubbling Cauldron of NGC 3079
22.08.2001

Edge-on spiral galaxy NGC 3079 is a mere 50 million light-years away toward the constellation Ursa Major. Shown in this stunning false-color Hubble Space Telescope image, the galaxy's disk - composed of spectacular star clusters in winding spiral arms and dramatic dark lanes of dust - spans some 70,000 light-years.

M51: X Rays from the Whirlpool
11.07.2002

Fresh from yesterday's episode, a popular pair of interacting galaxies known as the Whirlpool debut here beyond the realm of visible light -- imaged at high energies by the orbiting Chandra X-ray Observatory. Still turning in a remarkable performance, over 80 glitering x-ray stars are present in the Chandra image data from the region.

Light Echoes from V838 Mon
26.03.2003

Nominated for most mysterious star in the Milky Way, V838 Monocerotis briefly became one of the brightest stars in our galaxy. Its outburst discovered in January 2002, observations have indicated that V838 Mon somehow...

Binary Black Hole in 3C 75
12.04.2006

The two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are co-orbiting supermassive black holes powering the giant radio source 3C 75. Surrounded by multimillion degree x-ray emitting gas, and blasting out jets of relativistic particles the supermassive black holes are separated by 25,000 light-years.

Jupiter and the Red Spots
5.05.2006

Jupiter's Great Red Spot is a swirling storm seen for over 300 years, since the beginning of telescopic observations. But in February 2006, planetary imager Christopher Go noticed it had been joined by Red Spot Jr - formed as smaller whitish oval-shaped storms merged and then developed the remarkable reddish hue.

Illusion and Evolution in Galaxy Cluster Abell 2667
4.03.2007

What's happening to the galaxies of cluster Abell 2667? On the upper left, a galaxy appears to be breaking up into small pieces, while on the far right, another galaxy appears to be stretched like taffy.