The Hydra Cluster of Galaxies
16.04.2001

The Hydra Cluster of Galaxies contains well over 100 bright galaxies - but perhaps fewer galaxies than might be expected from its mass. Clusters of galaxies are the largest gravitationally bound objects in the universe.

The Perseus Cluster of Galaxies
5.04.1996

Here is one of the largest objects that anyone will ever see on the sky. Each of the fuzzy blobs in the above picture is a galaxy, together making up the Perseus Cluster, one of the closest clusters of galaxies.

Abell 2142: Clash of the Galaxy Clusters
6.03.2000

Over the course of billions of years, whole clusters of galaxies merge. Above is an X-ray image of Abell 2142, the result of the collision of two huge clusters of galaxies, and one of the most massive objects known in the universe.

Giant Cluster Bends Breaks Images
23.08.2015

What are those strange blue objects? Many of the brightest blue images are of a single, unusual, beaded, blue, ring-like galaxy which just happens to line-up behind a giant cluster of galaxies. Cluster galaxies here typically appear yellow and -- together with the cluster's dark matter -- act as a gravitational lens.

Gravity s Grin
27.11.2015

Albert Einstein's general theory of relativity, published 100 years ago this month, predicted the phenomenon of gravitational lensing. And that's what gives these distant galaxies such a whimsical appearance, seen through the looking glass of X-ray and optical image data from the Chandra and Hubble space telescopes.

The Perseus Cluster of Galaxies
20.05.2008

Here is one of the largest objects that anyone will ever see on the sky. Each of these fuzzy blobs is a galaxy, together making up the Perseus Cluster, one of the closest clusters of galaxies. The cluster is seen through a foreground of faint stars in our own Milky Way Galaxy.

Unexpected X Rays from Perseus Galaxy Cluster
2.01.2018

Why does the Perseus galaxy cluster shine so strangely in one specific color of X-rays? No one is sure, but a much-debated hypothesis holds that these X-rays are a clue to the long-sought identity of dark matter.

Gravity s Grin
26.10.2019

Albert Einstein's general theory of relativity, published over 100 years ago, predicted the phenomenon of gravitational lensing. And that's what gives these distant galaxies such a whimsical appearance, seen through the looking glass of X-ray and optical image data from the Chandra and Hubble space telescopes.

Fortuitous Flash Candidate for the Farthest Star Yet Seen
11.04.2018

Was this flash the farthest star yet seen? An unexpected flash of light noticed fortuitously on Hubble Space Telescope images may prove to be not only an unusual gravitational lensing event but also an image of a normal star 100 times farther away than any star previously imaged individually.

Gravity s Grin
5.08.2017

Albert Einstein's general theory of relativity, published over 100 years ago, predicted the phenomenon of gravitational lensing. And that's what gives these distant galaxies such a whimsical appearance, seen through the looking glass of X-ray and optical image data from the Chandra and Hubble space telescopes.