The Matter of Galaxy Clusters
24.10.2001

Situated over 2,000,000,000 (two billion) light-years from Earth, galaxies in cluster Abell 2390 (top) and MS2137.3-2353 (bottom) are seen in the right hand panels above, false-color images from the Hubble Space Telescope. Corresponding panels on the left reveal each cluster's x-ray appearance in images from the Chandra X-ray Observatory.

MACSJ0025: Two Giant Galaxy Clusters Collide
17.09.2008

What happens when two of the largest objects in the universe collide? No one was quite sure, but the answer is giving clues to the nature of mysterious dark matter. In the case of MACSJ0025.

Grand Spiral Galaxy M81 and Arps Loop
16.04.2013

One of the brightest galaxies in planet Earth's sky is similar in size to our Milky Way Galaxy: big, beautiful M81. This grand spiral galaxy lies 11.8 million light-years away toward the northern constellation of the Great Bear (Ursa Major).

Galaxies and the South Celestial Pole
31.12.2020

The South Celestial Pole is easy to spot in star trail images of the southern sky. The extension of Earth's axis of rotation to the south, it's at the center of all the southern star trail arcs.

JKCS041: The Farthest Galaxy Cluster Yet Measured
27.10.2009

What if we could see back to the beginning of the universe? We can -- since it takes the age of the universe for light to cross the universe. Peering at distant objects, therefore, tells us about how the universe used to be, even near its beginning.

Giant Galaxy NGC 6872
3.04.2011

Over 400,000 light years across NGC 6872 is an enormous spiral galaxy, at least 4 times the size of our own, very large, Milky Way. About 200 million light-years distant, toward the southern...

NGC 253: The Silver Coin Galaxy
13.04.2020

NGC 253 is one of the brightest spiral galaxies visible, but also one of the dustiest. Dubbed the Silver Coin for its appearance in smalltelescopes, it is more formally known as the Sculptor Galaxy for its location within the boundaries of the southern constellation Sculptor.

Plasma Jets from Radio Galaxy Hercules A
5.12.2012

Why does this galaxy emit such spectacular jets? No one is sure, but it is likely related to an active supermassive black hole at its center. The galaxy at the image center, Hercules A, appears to be a relatively normal elliptical galaxy in visible light.

Galaxy And Gamma Ray Burst
24.01.1999

Gamma-ray bursts rule the high-energy sky and Saturday another brief, intense flash of gamma-rays from the cosmos triggered space-based detectors. The orbiting Compton Observatory's BATSE instrument quickly relayed the burst's approximate location to fast-slewing, ground-based cameras primed to search for an elusive optical flash.

APOD: 2008 January 2- A Galaxy is not a Comet
1.01.2008

This gorgeous galaxy and comet portrait was recorded on December 30th, in the skies over Hoogeveen, The Netherlands. The combined series of 60 x 60 second exposures finds the lovely green coma of Comet 8P/Tuttle near its predicted conjunction with the Triangulum Galaxy.