Michael R. Blanton, New York University
Matthew A. Bershady, University of Wisconsin - Madison
Bela Abolfathi, University of California - Irvine
Franco D. Albareti, Universidad Autónoma de Madrid, Spain
Carlos Allende Prieto, Instituto de Astrofísica de Canarias, Spain
Andres Almeida, Universidad de La Serena, Chile
Javier Alonso-García, Universidad de Antofagasta, Chile
Friedrich Anders, Leibniz-Institut fuer Astrophysik Potsdam (AIP), Germany
Scott F. Anderson, University of Washington
Brett Andrews, University of Pittsburgh
Erik Aquino-Ortíz, Universidad Nacional Autónoma de México, Mexico
Alfonso Aragón-Salamanca, University of Nottingham, UK
Maria Argudo-Fernández, Universidad de Antofagasta, Chile
Eric Armengaud, Centre de Saclay, France
Eric Aubourg, University of Paris Diderot, France
Vladimir Avila-Reese, Universidad Nacional Autónoma de México, Mexico
Carles Badenes, University of Pittsburgh
Stephen Bailey, Lawrence Berkeley National Laboratory
Kathleen A. Barger, Texas Christian University
Jorge Barrera-Ballesteros, Johns Hopkins University
Curtis Bartosz, University of Washington
Dominic Bates, University of St Andrews, UK
Falk Baumgarten, Leibniz-Institut fuer Astrophysik Potsdam (AIP), Germany
Julian Bautista, University of Utah
Rachael Beaton, The Observatories of the Carnegie Institution for Science
Francesco Belfiore, University of Cambridge, UK
Chad F. Bender, The University of Arizona
Andreas A. Berlind, Vanderbilt University
Mariangela Bernardi, University of Pennsylvania
Florian Beutler, University of Portsmouth, UK
Renbin Yan, University of KentuckyFollow
Daniel Lazarz, University of KentuckyFollow
Kai Zhang, University of Kentucky


We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z ~ 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z ~ 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.

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Notes/Citation Information

Published in The Astronomical Journal, v. 154, no. 1, 28, p. 1-35.

© 2017. The American Astronomical Society. All rights reserved.

Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author (s) and the title of the work, journal citation and DOI.

Due to the large number of authors, only the first 30 and the authors affiliated with the University of Kentucky are listed in the author section above. For the complete list of authors, please download this article.

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Funding Information

Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High-Performance Computing at the University of Utah.