Looking in all the Right Places – The SLOAN DIGITAL SKY SURVEY Extends its Reach
July 17, 2014
Building on the past successes, the Sloan Digital Sky Survey (SDSS) collaboration has launched a major new program that will expand the census of the Universe into new areas. The new survey is a collaboration of more than 200 astronomers at more than 40 institutions on four continents, and incorporates telescopes in both the Northern and Southern Hemispheres to explore the entire sky for the first time.
Over the last fourteen years, many astronomers have used SDSS data to make numerous discoveries related to the large-scale structure of the Universe, the secrets of distant Quasars, the Milky Way or even solar system objects.
"MPIA was the first European partner institute in SDSS and the only one to participate since the inception of the survey", says MPIA director Hans-Walter Rix. "The new phase of SDSS will provide a vast new database of observations that will significantly expand our understanding of the Milky Way and of the nature of the Universe at all scales".
Measuring the compositions, positions, and motions of individual stars will reveal how our Milky Way Galaxy evolved from the distant past to today. Using two telescopes in both hemispheres – the Sloan Foundation 2.5-meter Telescope in New Mexico and now also the 2.5-meter Irenee du Pont Telescope at Las Campanas Observatory in Chile – will finally provide a consistant 360-degree view of the Milky Way.
Detailed maps of thousands of near and moderate distant galaxies will be used to determine their evolution over billions of years. This will be possible with a new cutting-edge measurement device consisting of bundling sets of fiber optic cables collecting light from across the entire faces of more than 10.000 galaxies.
Furthermore, a new set of very distant galaxies and quasars will allow astronomers to precisely measure the expansion history of the universe through 80% of cosmic history, helping to improve constraints on the nature of the mysterious dark energy.
Video: Changing a cartridge, opening the enclosure, sunset, and nightly observing at the Sloan Foundation 2.5m Telescope at Apache Point Observatory, Sunspot, New Mexico. During the night, an observer changes the cartridge to observe a new set of stars or galaxies roughly every hour. Each cartridge contains hundreds of fiber-optic cables plugged into holes in a large aluminum plate. Each fiber observes a single star or galaxy. The "bright time" observing is during full moon, the "dark time" is before moonrise, with the moon (not the sun!) rising shortly before the end of the video. The orange glow in the background is from the city of El Paso, Texas, 90 miles to the south. The lights briefly shining through the telescope petals before and after cartridge changes are calibration sequences. We use different light sources to check that all parts of the instrument see light the same way and to compare the observations to known standards.
Credit: John Parejko (Yale University) and the SDSS collaboration [Video on Youtube]
About the SLOAN DIGITAL SKY SURVEY
Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High-Performance Computing at the University of Utah. The SDSS web site is www.sdss.org.
SDSS-IV is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration including the Carnegie Institution for Science, Carnegie Mellon University, the Chilean Participation Group, Harvard-Smithsonian Center for Astrophysics, Instituto de Astrofisica de Canarias, The Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe (IPMU) / University of Tokyo, Lawrence Berkeley National Laboratory, Leibniz Institut für Astrophysik Potsdam (AIP), Max-Planck-Institut für Astrophysik (MPA Garching), Max-Planck-Institut für Extraterrestrische Physik (MPE), Max-Planck-Institut für Astronomie (MPIA Heidelberg), National Astronomical Observatory of China, New Mexico State University, New York University, The Ohio State University, Pennsylvania State University, Shanghai Astronomical Observatory, United Kingdom Participation Group, Universidad Nacional Autonoma de Mexico, University of Arizona, University of Colorado Boulder, University of Portsmouth, University of Utah, University of Washington, University of Wisconsin, Vanderbilt University, and Yale University.