SDSS-II will Map the Universe, the Milky Way and Dark Energy

http://www.sdss.org/news/releases/20050711.sdssII.html

A NEW SURVEY - SDSS-II will Map the Universe, the Milky Way and Dark
Energy
Sloan Digitcal Sky Survey
July 11, 2005


CONTACTS:

* Dr. Richard Kron, Director, The Sloan Digital Sky Survey II, only
by email at
* Dr. Michael Strauss, Scientific Spokesperson, Sloan Digital Sky
Survey II, (609) 258-3808,
* Gary S. Ruderman, Public Information Officer, The Sloan Digital
Sky Survey II, 312.320.4794,

Dr. Richard Kron, director of the Sloan Digital Sky Survey, announced a
new undertaking that will complete the largest survey of the universe.
This survey will add new partners and undertake new research missions,
and will run through summer 2008.

Late last month the funding package for a new, three-year venture
called
the Sloan Digital Sky Survey II (SDSS-II) was completed, led by the
Alfred P. Sloan Foundation of New York City, the National Science
Foundation (NSF), the U.S. Department of Energy and the member
institutions.

The SDSS has been carrying out a massive survey of the sky using a
dedicated 2.5-m telescope at Apache Point Observatory near Sunspot, New
Mexico. SDSS-II will complete observations of a huge contiguous region
of the Northern skies and will study the structure and origins of the
Milky Way Galaxy and the nature of dark energy.

The Sloan Digital Sky Survey is the most ambitious astronomical survey
project ever undertaken, already having measured precise brightnesses
and positions for hundreds of millions of galaxies, stars and quasars
during the last five years. The consortium of more than 300 scientists
and engineers at 23 institutions around the world -- and hundreds of
other scientists working in collaboration -- are using these data to
address fascinating and fundamental questions about the universe.

The exciting results from the SDSS data to date include the discovery
of
distant quasars seen when the universe was just 900 million years old;
the definitive measurement of the large-scale distribution of galaxies,
confirming the role of gravity in growing structures in the universe;
and evidence that the Milky Way Galaxy grew by cannibalizing smaller
companion galaxies.

"We are very excited with the funding agencies' decision to support
this
important mission," said Kron of the University of Chicago. "The
dedicated scientists and engineers of the Sloan Digital Sky Survey have
worked tirelessly to open new ways of seeing the Universe.

"We believe the SDSS II discoveries that lie ahead will further
scientific discoveries and lay the groundwork for future astronomical
exploration. We are sure that the data released to the public will
yield
discoveries for years to come."

In the last five years, the SDSS has released data for almost 200
million objects to the public. These data have been used by hundreds of
researchers around the world for scientific projects ranging from
studies of nearby stars to explorations of the nature of galaxies.

"We are proud of the landmark contributions made by the Sloan Digital
Sky Survey to our understanding of the evolution and structure of the
universe and enthusiastically support this next phase of research,"
said
Doron Weber, program director of the Alfred P. Sloan Foundation. "The
findings of the Sloan Digital Sky Survey have already produced the most
accurate picture of the skies that has ever existed and we expect new
discoveries that will continue to transform our knowledge of the
universe."

Eileen D. Friel, Executive Officer of the Division of Astronomical
Sciences at the National Science Foundation, said the Sloan Digital Sky
Survey "has enabled a remarkable array of scientific results, sometimes
in unexpected areas. The completion of the original survey and its
extension to address issues in galactic and stellar astronomy promises
to strengthen the legacy of the survey and to make it an even more
valuable resource for astronomers and educators."

And Robin Staffin, Associate Director of Science for High Energy
Physics
in the Department of Energy's Office of Science, said the agency was
"delighted to see the Sloan Digital Sky Survey entering this new phase.
SDSS has already contributed a great deal to our understanding of the
fundamental structure of the universe, and has helped pioneer the
connections between particle physics and cosmology. We expect that
great
science will come out of SDSS-II over the next few years."

With the formation of SDSS-II, eight new institutions join the
collaboration: American Museum of Natural History in New York City, the
University of Basel (Switzerland), Cambridge University (UK), Case
Western Reserve University in Cleveland, Ohio, the Joint Institute for
Nuclear Astrophysics (University of Notre Dame, Michigan State
University, and The University of Chicago), The Kavli Institute for
Particle Astrophysics and Cosmology at Stanford, Ohio State University,
and the Astrophysical Institute Potsdam (Germany). (A complete list of
SDSS-I and SDSS-II partners can be found below).

SDSS-II has three components. The first, called LEGACY, will complete
the SDSS survey of the extragalactic universe, obtaining images and
distances of nearly a million galaxies and quasars over a continuous
swath of sky in the Northern Hemisphere.

The new funding also inaugurates the second part of SDSS-II, the Sloan
Extension for Galactic Understanding and Exploration (SEGUE), mapping
the structure and stellar makeup of the Milky Way Galaxy, and gathering
data on how the Milky Way formed and evolved.

"The SEGUE project will allow us for the first time to get a 'big
picture' of the structure of our own Milky Way," explained consortium
member Heidi Newberg of Rensselaer Polytechnic Institute. "The mapping
of the Milky Way is more than an exercise in cartography. Ages,
chemical
compositions, and space distribution of stars are major clues to
understanding how our own Galaxy formed, and, by example, how galaxies,
in general. formed.

"Identifying the oldest stars will help us understand how the elements
of the periodic table were formed long ago inside of stars," Newberg
said.

The final piece of SDSS-II includes an intensive study of supernovae,
sweeping the sky to find these remnants of gigantic explosions from
dying stars. Astronomers can precisely measure the distances of distant
supernovae, using them to map the rate of expansion of the universe.

"This study will help to verify and quantify one of the most important
discoveries of modern science - the existence of the cosmological dark
energy," explained consortium member Andy Becker of the University of
Washington.

Becker explained that the SDSS telescope is uniquely positioned to both
discover, and follow up on, a wealth of supernovae at distances at
which
other surveys have found very few objects. This allows a direct
measurement of the effects of dark energy on the geometry of the
universe as a whole.

ABOUT THE SLOAN DIGITAL SKY SURVEY II

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

The SDSS is managed by the Astrophysical Research Consortium for the
Participating Institutions. The institutions that enabled SDSS-I and
SDSS-II a the American Museum of Natural History, the University of
Basel, Cambridge University, Case Western Reserve University, the
University of Chicago, Fermilab, The Institute for Advanced Study, the
Japan Participation Group, the Johns Hopkins University, the Joint
Institute for Nuclear Astrophysics, the Kavli Institute for Particle
Astrophysics and Cosmology, the Korean Scientist Group, Los Alamos
National Laboratory, the Ohio State University, the
Max-Planck-Institute
for Astronomy, the Max-Planck-Institute for Astrophysics, New Mexico
State University, University of Pittsburgh, University of Portsmouth,
Astrophysical Institute Potsdam, Princeton University, the United
States
Naval Observatory and the University of Washington.