From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Subject: Hubble Images Distant Galaxies Through Cosmic "Zoom Lens"
HUBBLE IMAGES DISTANT GALAXIES THROUGH COSMIC "ZOOM LENS"
A new image taken with NASA's Hubble Space Telescope of the galaxy
cluster Abell 2218--a spectacular example of gravitational lensing--is
available via the Internet and NASA's Imaging Branch.
The cluster is so massive and compact that light rays passing through
it are deflected by its enormous gravitational field, much as an optical
lens bends light to form an image. The process provides a powerful
"zoom lens" for viewing galaxies that are so far away they could not
normally be observed with the largest available telescopes.
The arc-like images distributed over the field of view like a spider web
are an illusory effect caused by the gravitational field of the cluster
which magnifies, brightens and distorts images of objects that lie far
beyond the cluster.
The arcs represent the distorted images of a very distant galaxy
population extending 5-10 times farther from Earth than the lensing
cluster. This population existed when the universe was just one quarter
of its present age, and contains valuable clues as to the early
evolution of galaxies. The image was taken with the Wide Field
Planetary Camera 2.
Imaging Branch Photo number: B&W: 95-H-141
Internet Addresses: ftp: ftp.stsci.edu
(IP address: 130.167.1.2)
WWW URL: http://www.stsci.edu
Gopher: www.stsci.edu
Via anonymous ftp: ftp.stsci.edu in /pubinfo:
(format) GIF /pubinfo/gif/A2218.gif
JPEG /pubinfo/jpeg/A2218.jpg
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- T o d d E. V a n H o o s e a r -
``'''vanhoose@lalaland.cl.msu.edu - vanhoose@msu.edu - vanhoose@lalaland.cl.msu.edu
(._.) Michigan State University - East Lansing, MI USA
(_) Computer Laboratory - Department of Communication
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