New Worlds, New Horizons in Astronomy and Astrophysics New Worlds, New Horizons in Astronomy and Astrophysics Committee for a Decadal Survey of Astronomy and Astrophysics Board on Physics and Astronomy Space Studies Board Division on Engineering and Physical Sciences Copyright © National Academy of Sciences. All rights reserved. New Worlds, New Horizons in Astronomy and Astrophysics THE NATIONAL ACADEMIES PRESS 500 Fifth Street, N.W. Washington, DC 20001 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. This study was supported by Contract NNX08AN97G between the National Academy of Sciences and the National Aeronautics and Space Administration, Contract AST-0743899 between the National Academy of Sciences and the National Science Foundation, and Contract DE-FG02-08ER41542 between the National Academy of Sciences and the U.S. Department of Energy. Support for this study was also provided by the Vesto Slipher Fund. Any opinions, fndings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily refect the views of the agencies that provided support for the project. Cover: Complexity abounds in the universe, especially during the birth phases of stars and planetary systems. The M17 region, also known as the Omega Nebula, in the constellation Sagittarius is rich in massive stars, including those recently formed and already impacting their environment (bright nebulous regions—e.g., back lower), as well as those still in the process of formation within cold dense clouds (dark regions—e.g., front center). Provinces such as this within our galaxy and others allow astronomers to understand and quantify the cycling of matter and energy within the cosmic ecosystem. The image depicts mid-infrared emission at 3.6- to 24-micrometer wave- lengths as detected by NASA’s Spitzer Space Telescope, although the region has been studied from high-frequency gamma-ray to low-frequency radio energies. Image courtesy of NASA/JPL-Caltech. Dedication (p. xxxiii): Photo courtesy of American Astronomical Society. Library of Congress Cataloging-in-Publication Data National Research Council (U.S.). Committee for a Decadal Survey of Astronomy and Astrophysics. New worlds, new horizons in astronomy and astrophysics / Committee for a Decadal Survey of Astronomy and Astrophysics, Board on Physics and Astronomy, Space Studies Board, Division on Engineering and Physical Sciences. p. cm. Includes bibliographical references and index. ISBN 978-0-309-15802-2 (case bdg.) — ISBN 978-0-309-15799-5 (pbk.) — ISBN 978-0-309-15800-8 (pdf) 1. Astronomy—Research—Forecasting. 2. Astrophysics—Research—Forecasting. 3. Research—International cooperation. I. Title. QB61.N385 2011 520.72—dc22 2010044515 This report is available in limited quantities from the Board on Physics and Astronomy, 500 Fifth Street, N.W.,Washington, DC 20001; New Worlds, New Horizons in Astronomy and Astrophysics The National Academy of Sciences is a private, nonproft, self-perpetuating society of distinguished scholars engaged in scientifc and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal govern- ment on scientifc and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M. Vest is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to asso- ciate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientifc and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Charles M. Vest are chair and vice chair, respectively, of the National Research Council. www.national-academies.org Copyright © National Academy of Sciences. All rights reserved. New Worlds, New Horizons in Astronomy and Astrophysics Copyright © National Academy of Sciences. All rights reserved. New Worlds, New Horizons in Astronomy and Astrophysics COMMITTEE FOR A DECADAL SURVEY OF ASTRONOMY AND ASTROPHYSICS ROGER D. BLANDFORD, Stanford University, Chair MARTHA P. HAYNES, Cornell University, Vice Chair JOHN P. HUCHRA, Harvard University, Vice Chair MARCIA J. RIEKE, University of Arizona, Vice Chair LYNNE HILLENBRAND, California Institute of Technology, Executive Offcer STEVEN J. BATTEL, Battel Engineering LARS BILDSTEN, University of California, Santa Barbara JOHN E. CARLSTROM, University of Chicago DEBRA M. ELMEGREEN, Vassar College JOSHUA FRIEMAN, Fermi National Accelerator Laboratory FIONA A. HARRISON, California Institute of Technology TIMOTHY M. HECKMAN, Johns Hopkins University ROBERT C. KENNICUTT, JR., University of Cambridge JONATHAN I. LUNINE, University of Arizona and University of Rome, Tor Vergata CLAIRE E. MAX, University of California, Santa Cruz DAN McCAMMON, University of Wisconsin STEVEN M. RITZ, University of California, Santa Cruz JURI TOOMRE, University of Colorado SCOTT D. TREMAINE, Institute for Advanced Study MICHAEL S. TURNER, University of Chicago NEIL deGRASSE TYSON, Hayden Planetarium, American Museum of Natural History PAUL A. VANDEN BOUT, National Radio Astronomy Observatory A. THOMAS YOUNG, Lockheed Martin Corporation (retired) Staff DONALD C. SHAPERO, Director, Board on Physics and Astronomy (BPA) MICHAEL H. MOLONEY, Astro2010 Study Director and Director, Space Studies Board (SSB) BRANT L. SPONBERG, Senior Program Offcer, BPA (until December 2009) ROBERT L. RIEMER, Senior Program Offcer, BPA BRIAN D. DEWHURST, Program Offcer, Aeronautics and Space Engineering Board (until July 2009) JAMES C. LANCASTER, Program Offcer, BPA DAVID B. LANG, Program Offcer, BPA v Copyright © National Academy of Sciences. All rights reserved. New Worlds, New Horizons in Astronomy and Astrophysics TERI THOROWGOOD, Administrative Coordinator, BPA (from November 2009) CARMELA CHAMBERLAIN, Administrative Coordinator, SSB CATHERINE GRUBER, Editor, SSB CARYN J. KNUTSEN, Research Associate, BPA LaVITA COATES-FOGLE, Senior Program Assistant, BPA (until October 2009) BETH DOLAN, Financial Associate, BPA vi Copyright © National Academy of Sciences. All rights reserved. New Worlds, New Horizons in Astronomy and Astrophysics SCIENCE FRONTIERS PANELS Panel on Cosmology and Fundamental Physics DAVID N. SPERGEL, Princeton University, Chair DAVID WEINBERG, Ohio State University, Vice Chair RACHEL BEAN, Cornell University NEIL CORNISH, Montana State University JONATHAN FENG, University of California, Irvine ALEX V. FILIPPENKO, University of California, Berkeley WICK C. HAXTON, University of California, Berkeley MARC P. KAMIONKOWSKI, California Institute of Technology LISA RANDALL, Harvard University EUN-SUK SEO, University of Maryland DAVID TYTLER, University of California, San Diego CLIFFORD M. WILL, Washington University Panel on the Galactic Neighborhood MICHAEL J. SHULL, University of Colorado, Chair JULIANNE DALCANTON, University of Washington, Vice Chair LEO BLITZ, University of California, Berkeley BRUCE T. DRAINE, Princeton University ROBERT FESEN, Dartmouth University KARL GEBHARDT, University of Texas JUNA KOLLMEIER, Observatories of the Carnegie Institution of Washington CRYSTAL MARTIN, University of California, Santa Barbara JASON TUMLINSON, Space Telescope Science Institute DANIEL WANG, University of Massachusetts DENNIS ZARITSKY, University of Arizona STEPHEN E. ZEPF, Michigan State University Panel on Galaxies Across Cosmic Time C. MEGAN URRY, Yale University, Chair MITCHELL C. BEGELMAN, University of Colorado, Vice Chair ANDREW J. BAKER, Rutgers University NETA A. BAHCALL, Princeton University ROMEEL DAVÉ, University of Arizona TIZIANA DI MATTEO, Carnegie Mellon University HENRIC S. W. KRAWCZYNSKI, Washington University vii Copyright © National Academy of Sciences. All rights reserved. New Worlds, New Horizons in Astronomy and Astrophysics JOSEPH MOHR, University of Illinois at Urbana-Champaign RICHARD F. MUSHOTZKY, NASA Goddard Space Flight Center CHRIS S. REYNOLDS, University of Maryland ALICE SHAPLEY, University of California, Los Angeles TOMMASO TREU, University of California, Santa Barbara JAQUELINE H. VAN GORKOM, Columbia University ERIC M. WILCOTS, University of Wisconsin Panel on Planetary Systems and Star Formation LEE W. HARTMANN, University of Michigan, Chair DAN M. WATSON, University of Rochester, Vice Chair HECTOR ARCE, Yale University CLAIRE CHANDLER, National Radio Astronomy Observatory DAVID CHARBONNEAU, Harvard University EUGENE CHIANG, University of California, Berkeley SUZAN EDWARDS, Smith College ERIC HERBST, Ohio State University DAVID C. JEWITT, University of California, Los Angeles JAMES P. LLOYD, Cornell University EVE C. OSTRIKER, University of Maryland DAVID J. STEVENSON, California Institute of Technology JONATHAN C. TAN, University of Florida Panel on Stars and Stellar Evolution ROGER A. CHEVALIER, University of Virginia, Chair ROBERT P. KIRSHNER, Harvard-Smithsonian Center for Astrophysics, Vice Chair DEEPTO CHAKRABARTY, Massachusetts Institute of Technology SUZANNE HAWLEY, University of Washington JEFFREY R. KUHN, University of Hawaii STANLEY OWOCKI, University of Delaware MARC PINSONNEAULT, Ohio State University ELIOT QUATAERT, University of California, Berkeley SCOTT RANSOM, National Radio Astronomy Observatory HENDRIK SCHATZ, Michigan State University LEE ANNE WILLSON, Iowa State University STANFORD E. WOOSLEY, University of California, Santa Cruz viii Copyright © National Academy of Sciences. All rights reserved. New Worlds, New Horizons in Astronomy and Astrophysics Staff DONALD C. SHAPERO, Director, Board on Physics and Astronomy (BPA) MICHAEL H. MOLONEY, Astro2010 Study Director and Director, Space Studies Board (SSB) BRANT L. SPONBERG, Senior Program Offcer, BPA (until December 2009) ROBERT L. RIEMER, Senior Program Offcer, BPA DAVID B. LANG, Program Offcer, BPA CARMELA CHAMBERLAIN, Administrative Coordinator, SSB CATHERINE GRUBER, Editor CARYN J. KNUTSEN, Research Associate, BPA LaVITA COATES-FOGLE, Senior Program Assistant, BPA (until October 2009) BETH DOLAN, Financial Associate, BPA ix Copyright © National Academy of Sciences. All rights reserved.