The Coma Cluster of Galaxies
12.12.1997

Almost every object in the above photograph is a galaxy. The Coma Cluster of Galaxies pictured is one of the densest clusters known - it contains thousands of galaxies. Each of these galaxies house billions of stars - just as our own Milky Way Galaxy does.

A Galaxy Gravitational Lens
19.12.1995

Sometimes it takes a keen eye to see a good mirage. Around the center of the red galaxy image in the above photograph lie four blue "smudges." Each smudge is actually a different image of the same background quasar. The central galaxy happens to fall directly in the light path of the quasar.

M80: A Dense Globular Cluster
7.07.1999

If our Sun were part of M80, the night sky would glow like a jewel box of bright stars. M80, also known as NGC 6093, is one of about 250 globular clusters that survive in our Galaxy.

A Gallery of Gravitational Mirages
1.06.1999

The deeper you peer into the universe, the harder it is to see straight. The reason is that distant galaxies act as gravitational lenses, deflecting light that passes nearby. These deflections result in the distortion of background sources, and in some cases the creation of multiple images.

The Einstein Cross Gravitational Lens
10.10.2000

Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible in this image. The central cloverleaf is rather light emitted from a background quasar.

PG 1115: A Ghost of Lensing Past
1.11.1998

In this tangle of quasars and galaxies lies a clue to the expansion rate of the universe. A diffuse glow evident in the picture on the left reveals a normal elliptical galaxy. Directly behind this galaxy lies a normal quasar.

SDSSJ1430: A Galaxy Einstein Ring
28.07.2008

What's large and blue and can wrap itself around an entire galaxy? A gravitational lens mirage. Pictured above on the left, the gravity of a normal white galaxy has gravitationally distorted the light from a much more distant blue galaxy.

Cosmic Collisions in a Galaxy Cluster
22.07.1999

Hundreds of galaxies appear as faint smudges of light in this Hubble Space Telescope picture of galaxy cluster MS1054-03. Eight billion light-years away, the cluster is among the most distant known clusters of galaxies and is now reported to contain the largest number of colliding galaxies ever found in a cluster.

A Peculiar Cluster of Galaxies
29.09.1998

Far across the universe, an unusual cluster of galaxies has been evolving. A diverse group of galaxies populate this cluster, including, on the left, an unusual galaxy showing an equatorial polar ring and a large spiral. Above looms a large elliptical galaxy.

The Hercules Cluster of Galaxies
19.07.2007

These are galaxies of the Hercules Cluster, an archipelago of island universes a mere 500 million light-years away. Also known as Abell 2151, this cluster is loaded with gas and dust rich, star-forming spiral galaxies but has relatively few elliptical galaxies, which lack gas and dust and the associated newborn stars.