Explanation:
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.
The cluster is seen through the foreground of faint stars in our own
Milky Way Galaxy.
It takes light roughly 300 million years to get here
from this region of the Universe, so we see this
cluster as it existed before the age of the
dinosaurs.
Also known as Abell 426, the center of the
Perseus Cluster is a prodigious source of
X-ray radiation, and so helps astronomers explore
how clusters formed and how gas and
dark matter interact.
The Perseus Cluster of Galaxies is part of the
Pisces-Perseus supercluster of galaxies, which spans over
15 degrees and contains over 1000 galaxies.
