Abstract

Each night, we are able to gaze up at the night sky and look at the thousands of stars that stretch to the end of our individual horizons. But the stars we see are only those that make up our own Milky Way galaxy—but one of hundreds of billions in the whole of the universe, each separated  by inconceivably huge tracts of empty space. In this book, astronomer James Geach tells the rich stories of both the evolution of galaxies and our ability to observe them, offering a fascinating history of how we’ve come to realize humanity’s tiny place in the vast universe.
           
Taking us on a compelling tour of the state-of-the-art science involved in mapping the infinite, Geach offers a first-hand account of both the science itself and how it is done, describing what we currently know as well as that which we still do not. He goes back one hundred years to when scientists first proved the existence of other galaxies, tracking our continued improvement in the ability to collect and interpret the light that stars in faraway galaxies have emitted through space and time. He discusses examples of this rapidly accelerating research, from the initial discovery that the faint “spiral nebulae” were actually separate star systems located far beyond the Milky Way to the latest observations of the nature of galaxies and how they have evolved. He also delves into the theoretical framework and simulations that describe our current “world model” of the universe.
           
With one hundred superb color illustrations, Galaxy is an illuminating guide to the choreography of the cosmos and how we came to know our place within it that will appeal to any stargazer who has wondered what was beyond their sight.  

“Galaxies represent the visible fabric of the universe and Geach brings his personal experience to the fore in describing the latest discoveries in this rapidly developing field of cosmology and galaxy evolution. He has a refreshing style of writing, and I highly recommend this book for those wanting to share in the excitement of modern astronomy.” — Richard Ellis, California Institute of Technology
“Geach is actively researching on one of the most exciting frontiers of today’s science: extragalactic astronomy. His book conveys his personal enthusiasm and offers a clear and highly readable survey of the field’s progress and prospects.”  
— Martin Rees FRS, Institute of Astronomy, Cambridge
“Galaxies are the building blocks of the universe. But they are dynamic blocks that have changed and evolved throughout the 13 billion years since their seeds—sown at the very instant of the Big Bang—began to grow. Their trials and tribulations are recounted with great clarity in this short, accessible, yet deep and comprehensive book. What are galaxies made of; why do they have different sizes, luminosities, and morphologies; and how have they managed to grow gigantic black holes in their midst—all these questions are posed, and answered as far as current knowledge permits, in an engaging and absorbing way by Geach. As a practicing professional astronomer at the cutting edge of galaxy research, Geach has managed to convey the vibrancy and excitement of research at the very forefront of human knowledge.”   — Carlos Frenk FRS, Durham University
“Astrophysicist Geach goes an order of magnitude further than the usual popular astronomy title—those full of breathtaking images, but little in the way of context—by giving readers the fascinating stories revealed by those images: how galaxies are created, how they evolve, and what they tell us about our universe. The sheer variety is stunning. . . . Gorgeous color photos, coupled with clear and engaging explanations of the science behind them, make this book a winner on every level.” — Publishers Weekly
“Book of the Month. . . . Galaxy: Mapping the Cosmos is a beautifully illustrated exploration of the Universe beyond the Milky Way and the mysteries and wonders of extragalactic astronomy. Geach is ideally placed to be our guide on this journey—a researcher in the fast-changing field of galaxy evolution, he displays both breadth and depth of knowledge, happily matched by a talent for engaging, nontechnical prose and an eye for a simile. His work with some of the biggest and most advanced of modern telescopes also provides the vicarious pleasure of some armchair astronomical tourism.”
— Sky at Night Magazine
“An excellent guide to a world many of us never get to see, both on and off this planet.”
— Focus Magazine
James Geach is a Royal Society University Research Fellow at the Centre for Astrophysics Research at the University of Hertfordshire, UK.