“Fascinating . . . One of the most important stories in the history of science.”— Washington Post In recent years, a handful of scientists has been racing to explain a disturbing aspect of our universe: only 4 percent of it consists of the matter that makes up you, me, and every star and planet. The rest is completely unknown. Richard Panek tells the dramatic story of how scientists reached this cosmos-shattering conclusion. In vivid detail, he narrates the quest to find the “dark” matter and an even more bizarre substance called dark energy that make up 96 percent of the universe. This is perhaps the greatest mystery in all of science, and solving it will bring fame, funding, and certainly a Nobel Prize. Based on hundreds of interviews and in-depth, on-site reporting, the book offers an intimate portrait of the bitter rivalries and fruitful collaborations, the eureka moments and blind alleys, that have redefined science and reinvented the universe. “A lively new account of twentieth-century (plus a little twenty-first-century) cosmology . . . The book is as much about how the science got done as about the science itself.”—Salon Richard Panek’s previous books include The Invisible Century and Seeing and Believing. The recipient of a Guggenheim fellowship in science writing, he has frequently written for the New York Times, as well as Discover, Smithsonian, Esquire, and Outside, among other publications.