What if we are not alone in the Cosmos?

For thousands of years, humans have wondered whether we're alone in the cosmos. Now, for the first time, we have the technology to investigate. But once you look for life elsewhere, you realize it is not so simple. How do you find it over cosmic distances?

With infectious enthusiasm, Dr. Kaltenegger takes us on an eye-opening journey to the most unusual exoplanets that have shaken our worldview - planets covered in oceans of lava, lonely wanderers lost in space, and others with more than one sun in their sky! And the best contenders for Alien Earths. In Alien Earths, she demonstrates how we can use our homeworld as a Rosetta Stone, creatively analyzing Earth's history and its astonishing biosphere to inform this search. We also see the imagined worlds of science fiction and how close they come to reality.

As our witty and knowledgeable tour guide, Dr. Kaltenegger shows how we discover not merely new continents, like the explorers of old, but whole new worlds circling other stars and how we could spot life there. Worlds from where aliens may even be gazing back at us. What if we're not alone?

Release Date: 16 April 2024 (US, UK Version), May 2nd (German Version)

Comments on Alien Earths

"In Alien Earths, Lisa Kaltenegger, a skillful educator, offers first-hand access to her expertise on the search for planets in the universe, and the life they may contain. Along the way, Lisa's breezy narrative style invites you to experience with her the challenges and joys of being a scientist on the frontier of discovery."
Neil deGrasse Tyson, Astrophysicist, American Museum of Natural History

"In Kaltenegger’s exhilarating exploration of the state of the Earth-hunting art, she welcomes us into the latest strategies for finding life at interstellar distances. Kaltenegger is that precious rarity, a leading scientist with an infectious passion for her subject and the talent to connect. Read this book and then gaze up at the night sky to find the stars sparkling even brighter with possibility." ―Ann Druyan, co-creator of Contact, co-writer Cosmos: Possible Worlds

"If you’ve ever wondered if we’re alone in the cosmos — and Dr. Kaltenegger is certain you have — start with Alien Earths. She’ll show you; the answer is in the sky, our window on the cosmos. Read on!" —Bill Nye, CEO, The Planetary Society (and former student of Carl Sagan)

"What a fascinating glimpse into the creative work of exobiologists, humankind's exciting search for life elsewhere in the universe, and the tantalizing facts we've learned thus far. I was enchanted."—Diane Ackerman, author of The Zookeeper's Wife

"Lisa Kaltenegger is an international leader in the discovery and analysis of exoplanets...Moreover, she is a brilliant expositor." ―Sir Martin John Rees, Fifteenth Astronomer Royal, bestselling author of If Science is to Save Us

"The odds are overwhelming that something’s alive out there. But will we ever see a sign of life on a planet circling a distant star? And, if we do, will we recognize it? This fascinating and tantalizing book points the way to YES." ―Alan Alda

"An engaging and personal book that couldn't be more up-to-date. Read Alien Earths, and feel your cosmic perspective shift just a little on its axis." ―Alastair Reynolds, science fiction writer and former ESA scientist

"In the grand tradition of Carl Sagan and Neil deGrasse Tyson, we now have a new tour guide to the cosmos."―Charles Cockell, Professor of Astrobiology, University of Edinburgh