A massive cluster of yellowish galaxies, seemingly caught in a red and blue spider web of eerily distorted background galaxies, makes for a spellbinding picture from the new Advanced Camera for Surveys aboard NASA's Hubble Space Telescope. Two billion
light-years away, galaxy cluster Abell 1689 is
one of the most massive objects in the Universe.In
from the Hubble Space Telescope's
Abell 1689 is seen to warp space as predicted by
theory of gravity -- bending light
from individual galaxies which lie
behind the cluster to produce multiple, curved images.
The power of this enormous
gravitational lens depends on its mass, but
the visible matter
in the form of the cluster's yellowish galaxies, only accounts
for about one percent of the mass needed to make the observed
bluish arcing images
of background galaxies.
In fact, most of the gravitational mass required
enough to explain this cosmic scale lensing is in the
form of still mysterious
As the dominant source of the cluster's gravity,
the dark matter's
unseen presence is mapped out
by the lensed arcs and
background galaxy images.
Credit: NASA, N. Benitez (JHU), T. Broadhurst (Racah Institute of Physics/The Hebrew University), H. Ford (JHU), M. Clampin (STScI), G. Hartig (STScI), G. Illingworth (UCO/Lick Observatory), the ACS Science Team and ESA
Available also in the Full Frame, uncropped, raw unprocessed Hubble format. The default is Standard Landscape, which is a slightly cropped image with some background noise elimnated to improve picture quality.