New Hubble data explains missing dark matter

New data from the NASA/ESA Hubble Space Telescope provides further evidence for tidal disruption in the galaxy NGC 1052-DF4. This result explains a previous finding that this galaxy is missing most of its dark matter. By ...

Cosmic furnace seen by X-ray observatory

This burst of color shows a fascinating discovery: a galaxy cluster acting as a cosmic furnace. The cluster is heating the material within to hundreds of millions of degrees Celsius—well over 25 times hotter than the core ...

Family tree of the Milky Way deciphered

Scientists have known for some time that galaxies can grow by the merging of smaller galaxies, but the ancestry of our own Milky Way galaxy has been a long-standing mystery. Now, an international team of astrophysicists has ...

Galaxies in the Perseus Cluster

For galaxies, as for people, living in a crowd is different from living alone. Recently, astronomers used the National Science Foundation's Karl G. Jansky Very Large Array (VLA) to learn how a crowded environment affects ...

New M92 stellar stream discovered

A team of astronomers using the Canada-France-Hawaii Telescope discovered a new stellar stream emanating from the M92 globular cluster. This new stream suggests that M92 is actively being disrupted by tidal forces caused ...

The spin of the supermassive black hole in the Milky Way

Once a black hole forms, its intense gravitational field produces a surface beyond which even light cannot escape, and it appears black to outsiders. All the details of the complex mix of matter and energy in its past are ...

Astronomers discover metal-poor globular cluster by chance

An international team of astronomers led by Soren Larsen (Radboud University, Nijmegen, The Netherlands) has accidentally discovered a globular cluster that contains extremely few metals, those elements heavier than hydrogen ...

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Galaxy groups and clusters

Galaxy groups and clusters are the largest known gravitationally bound objects to have arisen thus far in the process of cosmic structure formation. They form the densest part of the large scale structure of the universe. In models for the gravitational formation of structure with cold dark matter, the smallest structures collapse first and eventually build the largest structures, clusters of galaxies. Clusters are then formed relatively recently between 10 billion years ago and now. Groups and clusters may contain from ten to thousands of galaxies. The clusters themselves are often associated with larger groups called superclusters.

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