Photo courtesy of Anglo-Australian Observatories
An important clue in our quest to understand galaxies,
their formation and the large-scle structure of the universe came with
the discover by George Abell (and others) that galaxies tend to form in
clusters and that in turn, clusters associate into super-clusters.
The Virgo cluster of galaxies is made up of several thousand galaxies and
is about 50 million light years from us. It is much larger than the
small cluster (called the "local group") that contains our own Milky Way
galaxy.
Photo courtesy of Anglo-Australian
Observatories