Max Tegmark, Michael A. Strauss, Michael R. Blanton, Kevork Abazajian, Scott Dodelson, Havard Sandvik, Xiaomin Wang, David H. Weinberg, Idit Zehavi, Neta A. Bahcall, Fiona Hoyle, David Schlegel, Roman Scoccimarro, Michael S. Vogeley, Andreas Berlind, Tamás Budavari, Andrew Connolly, Daniel J. Eisenstein, Douglas Finkbeiner, Joshua A. Frieman, James E. Gunn, Lam Hui, Bhuvnesh Jain, David Johnston, Stephen Kent, Huan Lin, Reiko Nakajima, Robert C. Nichol, Jeremiah P. Ostriker, Adrian Pope, Ryan Scranton, Uroš Seljak, Ravi K. Sheth, Albert Stebbins, Alexander S. Szalay, István Szapudi, Yongzhong Xu, James Annis, J. Brinkmann, Scott Burles, Francisco J. Castander, Istvan Csabai, Jon Loveday, Mamoru Doi, Masataka Fukugita, Bruce Gillespie, Greg Hennessy, David W. Hogg, Željko Ivezić, Gillian R. Knapp, Don Q. Lamb, Brian C. Lee, Robert H. Lupton, Timothy A. McKay, Peter Kunszt, Jeffrey A. Munn, Liam O’Connell, John Peoples, Jeffrey R. Pier, Michael Richmond, Constance Rockosi, Donald P. Schneider, Christopher Stoughton, Douglas L. Tucker, Daniel E. Vanden Berk, Brian Yanny, Donald G. York Department of Physics, University of Pennsylvania, Philadelphia, PA 19104, USA; Dept. of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139; Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003; Princeton University Observatory, Princeton, NJ 08544, USA; Department of Physics, Drexel University, Philadelphia, PA 19104, USA; Department of Astronomy, Ohio State University, Columbus, OH 43210, USA; Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510, USA; Center for Cosmological Physics and Department of Astronomy & Astrophysics, University of Chicago, Chicago, IL 60637, USA; Department of Physics and Astronomy, The Johns Hopkins University, 3701 San Martin Drive, Baltimore, MD 21218, USA; University of Pittsburgh, Department of Physics and Astronomy, 3941 O’Hara Street, Pittsburgh, PA 15260, USA; Department of Astronomy, University of Arizona, Tucson, AZ 85721, USA; Department of Physics, 5000 Forbes Avenue, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA; Apache Point Observatory, 2001 Apache Point Rd, Sunspot, NM 88349-0059, USA; Institut d’Estudis Espacials de Catalunya/CSIC, Gran Capita 2-4, 08034 Barcelona, Spain; Sussex Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QJ, UK; Institute of Astronomy, Univ. of Tokyo, Kashiwa 277-8582, Japan; U.S. Naval Observatory, Flagstaff Station, Flagstaff, AZ 86002-1149, USA; Dept. of Physics, Univ. of Michigan, Ann Arbor, MI 48109-1120, USA; Physics Dept., Rochester Inst. of Technology, 1 Lomb Memorial Dr, Rochester, NY 14623, USA; Dept. of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802, USA; Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, USA; Theoretical Division, MS B285, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA;

The Sloan Digital Sky Survey has validated and made publicly available its First Data Release. This consists of 2099 square degrees of five-band (u g r i z) imaging data, 186,240 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 1360 square degrees of this area, and tables of measured parameters from these data. The imaging data go to a depth of r ≈ 22.6 and are photometrically and astrometrically calibrated to 2% rms and 100 milli-arcsec rms per coordinate, respectively. The spectra cover the range 3800–9200Å, with a resolution of 1800–2100. Further characteristics of the data are described, as are the data products themselves. Subject headings: Atlases—Catalogs—Surveys Enrico Fermi Institute, The University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637 Lawrence Berkeley National Laboratory, One Cyclotron Rd., Berkeley CA 94720-8160 Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QJ, United Kingdom Department of Physics, University of Michigan, 500 East University Ave., Ann Arbor, MI 48109 Institute for Astronomy Royal Observatory Blackford Hill Edinburgh EH9 3HJ Scotland Department of Physics, University of Pennsylvania, Philadelphia, PA 19104 Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180 Lucent Technologies, 2701 Lucent Lane, Lisle, IL 60532 Department of Astronomy and Research Center for the Early Universe, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan Joseph Henry Laboratories, Princeton University, Princeton, NJ 08544 School of Natural Sciences, Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 Physics Department, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603 Department of Astronomy and Astrophysics, the Pennsylvania State University, University Park, PA 16802 University of Zagreb, Department of Physics, Bijenička cesta 32, 10000 Zagreb, Croatia Institute for Astronomy, 2680 Woodlawn Road, Honolulu, HI 96822 University of Wyoming, Dept. of Physics & Astronomy, Laramie, WY 82071 Department of Physics, Drexel University, Philadelphia, PA 19104 Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85741 Garching, Germany Department of Astronomy, Ohio State University, Columbus, OH 43210

Max Tegmark, Michael A. Strauss, Michael R. Blanton, Kevork Abazajian, Scott Dodelson, Havard Sandvik, Xiaomin Wang, David H. Weinberg, Idit Zehavi, Neta A. Bahcall, Fiona Hoyle, David Schlegel, Roman Scoccimarro, Michael S. Vogeley, Andreas Berlind, Tamás Budavari, Andrew Connolly, Daniel J. Eisenstein, Douglas Finkbeiner, Joshua A. Frieman, James E. Gunn, Lam Hui, Bhuvnesh Jain, David Johnston, Stephen Kent, Huan Lin, Reiko Nakajima, Robert C. Nichol, Jeremiah P. Ostriker, Adrian Pope, Ryan Scranton, Uroš Seljak, Ravi K. Sheth, Albert Stebbins, Alexander S. Szalay, István Szapudi, Yongzhong Xu, James Annis, J. Brinkmann, Scott Burles, Francisco J. Castander, Istvan Csabai, Jon Loveday, Mamoru Doi, Masataka Fukugita, Bruce Gillespie, Greg Hennessy, David W. Hogg, Željko Ivezić, Gillian R. Knapp, Don Q. Lamb, Brian C. Lee, Robert H. Lupton, Timothy A. McKay, Peter Kunszt, Jeffrey A. Munn, Liam O’Connell, John Peoples, Jeffrey R. Pier, Michael Richmond, Constance Rockosi, Donald P. Schneider, Christopher Stoughton, Douglas L. Tucker, Daniel E. Vanden Berk, Brian Yanny, Donald G. York Department of Physics, University of Pennsylvania, Philadelphia, PA 19101, USA; Dept. of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139; Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003; Princeton University Observatory, Princeton, NJ 08544, USA; Department of Physics, Drexel University, Philadelphia, PA 19104, USA; Department of Astronomy, Ohio State University, Columbus, OH 43210, USA; Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510, USA; Center for Cosmological Physics and Department of Astronomy & Astrophysics, University of Chicago, Chicago, IL 60637, USA; Department of Physics and Astronomy, The Johns Hopkins University, 3701 San Martin Drive, Baltimore, MD 21218, USA; University of Pittsburgh, Department of Physics and Astronomy, 3941 O’Hara Street, Pittsburgh, PA 15260, USA; Department of Astronomy, University of Arizona, Tucson, AZ 85721, USA; Department of Physics, 5000 Forbes Avenue, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA; Apache Point Observatory, 2001 Apache Point Rd, Sunspot, NM 88349-0059, USA; Institut d’Estudis Espacials de Catalunya/CSIC, Gran Capita 2-4, 08034 Barcelona, Spain; Sussex Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QJ, UK; Inst. for Cosmic Ray Research, Univ. of Tokyo, Kashiwa 277-8582, Japan; U.S. Naval Observatory, Flagstaff Station, Flagstaff, AZ 86002-1149, USA; Dept. of Physics, Univ. of Michigan, Ann Arbor, MI 48109-1120, USA; Physics Dept., Rochester Inst. of Technology, 1 Lomb Memorial Dr, Rochester, NY 14623, USA; Dept. of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802, USA; Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, USA; Theoretical Division, MS B285, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA;