Explanation:
These are
galaxies of the Hercules Cluster, an archipelago of
"island universes" a mere 650 million light-years distant.
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.
Colors in the composite image show the star forming galaxies
with a blue tint and ellipticals with a slightly yellowish cast.
In this cosmic vista many galaxies seem to be
colliding or
merging
while others seem distorted - clear evidence that
cluster galaxies commonly interact.
Over time, the galaxy interactions are likely to affect the
the content of the cluster itself.
Researchers believe that the
HerculesCluster is significantly similar
to young galaxy clusters
in the distant, early Universe
and that exploring galaxy types and their interactions in nearby
Hercules will help unravel the threads
of galaxy andcluster evolution.