From: LARRY KLAES (ljk4_at_msn.com)
Date: Wed Sep 28 2005 - 12:51:01 UTC
>From: "NASA Jet Propulsion Laboratory" <info_at_jpl.nasa.gov>
>Reply-To: <info_at_jpl.nasa.gov>
>Subject: NASA Finds 'Big Baby' Galaxies in Newborn Universe
>Date: Tue, 27 Sep 2005 15:57:07 -0700
>
>MEDIA RELATIONS OFFICE
>JET PROPULSION LABORATORY
>CALIFORNIA INSTITUTE OF TECHNOLOGY
>NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
>PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
>http://www.jpl.nasa.gov
>
>Gay Yee Hill (818) 354-0344
>Jet Propulsion Laboratory, Pasadena, Calif.
>
>Ray Villard (410) 338-4514
>Space Telescope Science Institute, Baltimore, Md.
>
>Erica Hupp/George Deutsch (202) 358-1237/1324
>NASA Headquarters, Washington
>
>News Release: 2005-156 September 27, 2005
>
>NASA Finds 'Big Baby' Galaxies in Newborn Universe
>
>Two of NASA's Great Observatories, the Spitzer and Hubble Space Telescopes,
>have teamed up to
>"weigh" the stars in several distant galaxies. One of these galaxies, among
>the most distant ever
>seen, appears to be unusually massive and mature for its place in the young
>universe.
>
>This came as a surprise to astronomers. The earliest galaxies in the
>universe are commonly
>thought to have been much smaller associations of stars that gradually
>merged to build large
>galaxies like our Milky Way.
>
>"This galaxy, named HUDF-JD2, appears to have 'bulked up' amazingly
>quickly, within the first
>few hundred million years after the big bang. It made about eight times
>more mass in stars than are
>found in our own Milky Way today, and then, just as suddenly, it stopped
>forming new stars," said
>Dr. Bahram Mobasher of the Space Telescope Science Institute, Baltimore,
>and the European
>Space Agency, Paris.
>
>The galaxy was pinpointed among approximately 10,000 others in a small
>patch of sky called the
>Hubble Ultra Deep Field. The galaxy is believed to be about as far away as
>the most distant known
>galaxies. It represents an era when the universe was only 800 million years
>old. That is about five
>percent of the universe's age of 14 billion years.
>
>Scientists studying the Ultra Deep Field found this galaxy in Hubble's
>infrared images. They
>expected it to be young and small, like other known galaxies at similar
>distances. Instead, they
>found evidence the galaxy is remarkably mature and much more massive. Its
>stars appear to have
>been in place for a long time.
>
>Hubble's optical-light Ultra Deep Field image is the deepest image ever
>taken, yet this galaxy was
>not evident. This indicates much of the galaxy's optical light has been
>absorbed by traveling
>billions of light-years through intervening hydrogen gas. The galaxy was
>detected using Hubble's
>near-infrared camera and multi-object spectrometer. It was also detected by
>an infrared camera on
>the Very Large Telescope at the European Southern Observatory. At those
>longer infrared
>wavelengths, it is very faint and red.
>
>The big surprise is how much brighter the galaxy is in longer-wavelength
>infrared images from the
>Spitzer Space Telescope. Spitzer is sensitive to the light from older,
>redder stars, which should
>make up most of the mass in a galaxy. The infrared brightness of the galaxy
>suggests it is massive.
>"This would be quite a big galaxy even today," said Dr. Mark Dickinson of
>the National Optical
>Astronomy Observatory, Tucson, Ariz. "At a time when the universe was only
>800 million years
>old, it's positively gigantic."
>
>Spitzer observations were also independently reported by Dr. Laurence Eyles
>from the University
>of Exeter in the United Kingdom and Dr. Haojing Yan of the Spitzer Science
>Center, Pasadena,
>Calif. They also revealed evidence for mature stars in more ordinary, less
>massive galaxies at
>similar distances, when the universe was less than one billion years old.
>
>The new observations reported by Mobasher extend this notion of
>surprisingly mature "baby
>galaxies" to an object which is perhaps 10 times more massive, and which
>seemed to form its stars
>even earlier in the history of the universe.
>
>Mobasher's team estimated the distance to this galaxy by combining
>information provided by the
>Hubble, Spitzer, and Very Large Telescope observations. The relative
>brightness of the galaxy at
>different wavelengths is influenced by the expanding universe and allows
>astronomers to estimate
>its distance. They can also get an idea of the make-up of the galaxy in
>terms of the mass and age of
>its stars.
>
>While astronomers generally believe most galaxies were built piecewise by
>mergers of smaller
>galaxies, the discovery of this object suggests at least a few galaxies
>formed quickly long ago. For
>such a large galaxy, this would have been a tremendously explosive event of
>star birth.
>
>JPL manages the Spitzer Space Telescope mission for NASA. Science
>operations are conducted at
>the Spitzer Science Center at the California Institute of Technology in
>Pasadena.The Hubble Space
>Telescope is a project of international cooperation between NASA and the
>European Space
>Agency. The Very Large Telescope is a project of the European Southern
>Observatory at the
>Paranal Observatory in Atacama, Chile.
>
>For more information and additional images visit:
>http://www.spitzer.caltech.edu/Media and http://hubblesite.org/news/2005/28
>
>
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