Three of the Most Distant Quasars Found at Edge of the Universe

American Astronomical Society Meeting, Seattle, Washington —
An international team of scientists from the Sloan Digital Sky
Survey, including two astronomers from Penn State University,
announced today the discovery of three of the most distant
quasars, including the most distant quasar known. The
discoveries, described in a paper that will be published in
the April 2003 issue of The Astronomical Journal, relied
on observations by one of the world’s largest optical
telescopes — the 9.2-meter Hobby-Eberly Telescope — which
is partially owned and operated by Penn State.

Penn State Professor of Astronomy and astrophysics Donald
Schneider, who is the chairman of the Sloan Survey’s Quasar
Science Working Group, noted the key role played by the
Hobby-Eberly Telescope in the discovery of the first, third,
and fourth most distant quasars. “The Hobby-Eberly Telescope
staff deserve a great deal of credit for obtaining these
challenging observations,” he said. Niel Brandt, Associate
Professor of Astronomy and astrophysics at Penn State and
the leader of the Sloan Survey’s investigation of the X-ray
properties of distant quasars, also is an author on the
paper.

The astronomers report that the three quasars are hundreds
of times more luminous than our galaxy, and are probably
powered by black holes that are more than a billion times
the mass of the Sun. The radiation recorded from the
quasars last year left the objects when the universe was
just 800 million years old. “We are perhaps witnessing the
formation of the first large structures in the universe,”
said Brandt. “These objects may provide crucial insights
into how Nature manages to create large black holes and
galaxies.”

The discovery of the quasars required the efforts of many
scientists working with different telescopes, including
the Hobby-Eberly Telescope. Observations by the Sloan
Digital Sky Survey’s 2.5-meter telescope at Apache Point
Observatory in New Mexico first identified the objects as
possible distant quasars. The candidates were so faint —
emitting essentially no visible light — that only
near-infrared detectors could detect the objects.

Xiaohui Fan of Steward Observatory and Michael Strauss of
Princeton University carried out initial observations of
the quasar candidates with Apache Point’s 3.5-meter
telescope, but the objects were too faint for this
instrument to unambiguously determine their redshifts.
Larger telescopes, such as the 9.2-meter Hobby-Eberly and
10-meter Keck telescopes, were used in the late spring of
2002 to obtain high-quality data on the quasar candidates.

The distances to all three quasars were measured with data
obtained with the Hobby-Eberly Telescope’s Maracario
Low-Resolution Spectrograph, which was designed and built
by a team led by Gary Hill of the University of Texas.
“The queue-scheduled nature of the Hobby-Eberly Telescope
allowed it to acquire the data almost as soon as the
candidate quasars were identified,” said Larry Ramsey,
professor of astronomy and astrophysics at Penn State and
the Hobby-Eberly Telescope Project Scientist. “It is clear
that the Sloan Survey and the Hobby-Eberly Telescope are
a powerful combination for scientific discovery.”

Schneider notes that the three quasars were found when the
Sloan survey had covered only about a third of its planned
area. “In the next few years we hope to find more than a
dozen of these beacons from the universe’s infancy,” he
says. This work marks the eighth time that Schneider has
discovered the most-distant quasar.

“The Sloan survey has generated a sample of quasars that
stretches through almost all of cosmic time, from 800
million years after the Big Bang to the present,” explained
James Gunn of Princeton University, who is the Project
Scientist of the Sloan Digital Sky Survey. “These data
will be invaluable for the next major effort of the
survey’s quasar team, namely to characterize the evolution
of quasars from their formation to the present.”

A complete list of people contributing to the discoveries
of new, more-distant quasars is posted on the NEWS Section
of the Sloan Digital Sky Survey Web site at
http://www.sdss.org

[DPS/BKK]

ABOUT THE SLOAN DIGITAL SKY SURVEY:

The Sloan Digital Sky Survey (sdss.org) will map in detail
one-quarter of the entire sky, determining the positions
and absolute brightness of 100 million celestial objects.
It also will measure the distances to more than a million
galaxies and quasars. The Astrophysical Research Consortium
(ARC) operates Apache Point Observatory, site of the Sloan
Digital Sky Survey telescopes.

The Sloan Digital Sky Survey is a joint project of the
University of Chicago, Fermilab, the Institute for Advanced
Study, the Japan Participation Group, the Johns Hopkins
University, the Los Alamos National Laboratory, the
Max-Planck-Institute for Astronomy (MPIA), the
Max-Planck-Institute for Astrophysics (MPA), New Mexico
State University, the University of Pittsburgh, Princeton
University, the United States Naval Observatory, and the
University of Washington.

Funding for the project has been provided by the Alfred P.
Sloan Foundation, the Participating Institutions, the
National Aeronautics and Space Administration, the National
Science Foundation, the U.S. Department of Energy, the
Japanese Monbukagakusho, and the Max Planck Society.

ABOUT THE HOBBY-EBERLY TELESCOPE:

The Hobby-Eberly Telescope is a joint project of the
University of Texas at Austin, Penn State University,
Stanford University, Ludwig-Maxmillians-Universitat München,
and George-August-Universitat Göttingen. The Hobby-Eberly
Telescope is named in honor of its principal benefactors:
William P. Hobby, the former Lieutenant Governor of Texas,
and Robert E. Eberly of Pennsylvania, an industrialist and
philanthropist. The Maracario Low-Resolution Spectrograph
was constructed by the University of Texas at Austin,
Stanford University, Ludwig-Maxmillians-Universitat Munchen,
the Instituto de Astronomica de la Universidad de Mexico,
George-Agust-Universitat Göttingen, and Penn State
University. The instrument is named for Mike Marcario of
High Lonesome Optics, who fabricated several optical
elements for the spectrograph but died before its completion.

IMAGE CAPTIONS:

[Image 1:
http://sancerre.as.arizona.edu/%7Efan/PR/2002/z64.gif (924KB)]
Picture of redshift 6.4 Quasar

[Image 2:
http://sancerre.as.arizona.edu/%7Efan/PR/2002/z62.gif (924KB)]
Picture of redshift 6.2 Quasar

[Image 3:
http://sancerre.as.arizona.edu/%7Efan/PR/2002/z61.gif (924KB)]
Picture of redshift 6.1 Quasar

[Image 4:
http://sancerre.as.arizona.edu/%7Efan/PR/2002/spectra.gif (534KB)]
Spectra for all new z 6.0 quasars