Photo Acknowledgments

The images in this book are used with the permission of: © iStockphoto.com/maciek905 (design element throughout); X-ray: NASA/CXC/Caltech/P.Ogle et al.; Optical: NASA/STScI; IR: NASA/JPL-Caltech; Radio: NSF/NRAO/VLA, p. 4; © SSPL/Science Museum/Getty Images, p. 8; NASA, pp.10, 62, 69, 81, 84, 95, © Universal History Archive/UIG/Getty Images, p. 15;© ESA–C.Carreau, p. 18; © Laura Westlund/Independent Picture Service, pp. 19, 35, 43, 46, 65, 78; © AIP Emilio Segre Visual Archives, p. 21; © SSPL/Getty Images, p. 24; ktsdesign/Shutterstock.com, p. 29; NASA/Swift/Stefan Immler, p. 31; Courtesy of the Los Alamos National Laboratory Archives, p. 33;© Jesse Dittmar/Redux, p. 34; Richard Wainscoat/Alamy Stock Photo, p. 36; X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScI, p. 39; ESO/MPE/Marc Schartmann, p. 44; © ANNIE TRITT/The New York Times/Redux, p. 45; © 2013 Karwai Tang/Getty Images, p. 49; © Paul Ehrenfest (1880-1933)/Wikimedia Commons (public domain), p. 51; LIGO/Axel Mellinger, p. 54; Caltech/MIT/LIGO Lab, p. 56; Ann Feild (STScI)/NASA, p. 61; NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University), p. 70; NASA/JPL-Caltech, p. 72; NASA/CXC/W. Forman et al., p. 74; © Meridith Kohut/The New York Time/Redux, p. 76; NASA/CXC/SAO, pp. 87, 100, 102 (bottom); NASA/ESA, p. 90; NASA/Goddard Space Flight Center, p. 93; NASA, ESA, Digitized Sky Survey 2, p. 101.

Front cover: © iStockphoto.com/vchal.