|What are those strange blue objects?
Many of the brightest blue images are of a single,
unusual, beaded, blue, ring-like
galaxy which just happens to line-up behind a giant
cluster of galaxies.
Cluster galaxies here typically appear yellow and --
together with the cluster's dark matter --
act as a gravitational lens.
A gravitational lens can create several images of
analogous to the many points of light
one would see while looking through a wine glass at a distant street light.
The distinctive shape of this background galaxy --
which is probably just forming -- has allowed
astronomers to deduce that it has separate
images at 4, 10, 11, and 12
from the center of the cluster.
A blue smudge near the cluster center is likely
of the same background galaxy.
In all, a recent analysis postulated that at least 33 images of 11 separate background galaxies are discernable.
spectacular photo of galaxy cluster CL0024+1654 from the
Hubble Space Telescope
was taken in November 2004.
H. Lee &
(Johns Hopkins U.)