“In this delightful scientific chronicle of humanity’s quest for ‘other worlds’, astronomer Lucas Ellerbroek mixes memoir, history and meetings with remarkable planet hunters.”

Nature

“Are we alone in the universe? In Planet Hunters, Lucas Ellerbroek traces the story of this question from its beginnings during the age of Copernicus and Galileo to the present day, teaching us the relevant science as he goes. Ellerbroek is particularly skilled at inserting the ‘astronomy backstory,’ giving accessible introductions to both historical ideas and cutting-edge research, and showing how big questions are teased into empirical science.”

Science

“Ellerbroek examines how the first astronomers gazed at the stars—with the naked eye and then with early telescopes—and shares their thoughts and discoveries. As he does, he provides great examples to help readers understand the immense distances in space and the difficulties inherent in studying the ‘wobbles’ of stars and planets so many millions of miles away. . . . Meticulous and well-researched, but not dull, Planet Hunters is infused with the enthusiasm of the many people who have devoted their lives to searching for a potential neighbor in the enormity of space.”

Shelf Awareness

“It seems as though we’re discovering new exoplanets regularly, but one thing we haven’t found yet is life on them (let’s be real: That is probably going to take a very long time). But that doesn’t mean we’re not looking. Astronomer Ellerbroek takes readers on a journey through the history of looking through telescopes and searching for exoplanets, discussing the discovery of the first in 1995. It’s the history of exoplanets and a search for alien life, speaking with some of the people at the frontiers of this field.”

Unbound Worlds, Best Summer Books of 2017

“Planet Hunters traces the history of exoplanet discovery back to a time when the idea of planets beyond our solar system was just science fiction—or heresy. Ellerbroek describes the field of exoplanet research in all its historical context, from Giordano Bruno's heretical burning at the stake for suggesting that stars had planets of their own, to Bill Borucki's dedication to making the Kepler mission a reality. By uncovering the centuries of courage and creativity it took to make revolutionary discoveries in astronomy, Ellerbroek hopes readers will feel less intimidated by the sciences and more encouraged to innovate.”

Doris Elin Salazar | Space.com

"One of the best science books of the year. . . . The only planets known to exist in the universe twenty five years ago were the Earth and its near neighbors circling the sun. That all changed with the discovery of the first 'exoplanet' around another star; today, thousands have been catalogued. This lively volume reveals the human face of the researchers who search for the ultimate prize: proof of extraterrestrial life."

Sunday Times

"One of the must-read space books of 2017."

Space.com

“This book describes the discovery during the last twenty two years of an increasing number of exoplanets—nearly three thousand by the summer of 2016—and this is in itself a fascinating story. . . . Ellerbroek’s book is entertaining and contains much interesting information about important new astronomical techniques.”

The Observatory

"The author writes in an elegant, readable style that offers sufficient technical insight for the non-astronomer, but places the scientists and their work in an appropriate societal and human context. . . . The author has succeeded in bringing this exciting field to a wider audience with a very relaxed style that still pays due diligence to scientific rigor. The real appeal of the book is the human face the author gives to the pursuit of scientific knowledge."

Metascience

“Ellerbroek describes this voyage of discovery with enthusiastic energy.”

NRC Handelsblad

"From the burning of Giordano Bruno in 1600 for stating the universe was infinite to the launching of the Kepler satellite in 2009, this book recounts the search for planets outside the Solar System, known as exoplanets. Ellerbroek blends history and personal interviews with today's leading researchers, resulting in a uniquely personable approach that does not skimp on science. . . . This is an excellent read for anyone interested in exoplanet research and the astronomers who pursue it. A thorough list of references and chapter bibliographies provide direction for serious readers, though the text is accessible enough for the general reader as well. . . . Highly recommended."

Choice

Twenty years ago, humankind did not know whether most stars have planets or whether our Sun was unique with its array of orbiting planets. Today we know that most stars have planets (‘exoplanets’), many of the planets are Earth-size, and that there are billions of Earth-size planets orbiting in the habitable zone where life might evolve. Planet Hunters provides dozens of delightful (and sometimes humorous) histories of individuals who thought and wrote about planets and life around other stars before the recent discoveries provided facts. . . . Planet Hunters is both informative and a pleasure to read. I highly recommend it.”

William J. Borucki, Kepler Principal Investigator, NASA Ames Research Center

“Two dozen years ago, we didn’t know of any planets beyond the ones orbiting our own Sun. Since then we’ve learned that planets are as common as roof tiles. Ellerbroek has written a captivating, up-close-and-personal chronicle of this remarkable burst of discovery. Millennia from now, when the twenty-first century is no more than a footnote, our era will still be notable because the scientists described here opened our eyes to a myriad worlds, and quite possibly, a myriad places where life exists.”

Seth Shostak, senior astronomer, SETI Institute

“We are living in an exceptional epoch. Thanks to the development of technology, the ancient dreams of Greek philosophers have become an exciting field of modern astronomy. In this timely book, the characters who have participated in the discovery of these other worlds share their personal stories. Discoveries are made by individuals, thanks to their vision, enthusiasm, and perseverance, and also through friendship, collaboration, and competition. Planet Hunters is a lively fresco of that international endeavor.”

Michel Mayor, discoverer of the first exoplanet and emeritus professor of astrophysics, University of Geneva

“Ellerbroek is the Jacques Cousteau of the universe.”

Jelle Brandt Corstius

“A compelling adventure full of surprising details that show why astronomy is so fascinating.”

Robbert Dijkgraaf, Institute for Advanced Study