I remember being about nine years old and sitting with the son of family friends, discussing if there was life in outer space somewhere. We were both sure there was. Sixty some years later, science has yet to pin down a definitive answer to the question, but I don’t expect to be visited by War of the World type Martians or the giant robot from The Day the Earth Stood Still. What can we expect? And would alien life be recognizable to us any more than we could recognize it?

Alien Earths shares Dr. Lisa Kaltenegger’s quest to discover life in the cosmos. She asks important questions. What is life? What is a habitable world? How does one look for life in the cosmos? She explains the concepts with illustrations geared to the non-scientist.

The author also addresses the difficult environment female scientists face their entire life, counselors and educators and peers entrenched in the belief that women are incapable of making a career in the natural sciences.

Descriptions of alien worlds and the mysteries of life and the universe spur the imagination. We are taken across the known universe as she imagines the environments of other planets.

“If someone has found us already,” she ends, considering how we have impacted our planet for the worse, “I wonder what they think of us.”

Thanks to the publisher for a free book.

I received a gifted copy of ALIEN EARTHS: THE NEW SCIENCE OF PLANET HUNTING IN THE COSMOS by Lisa Kaltenegger from St. Martin’s Press. I also received the audiobook from Macmillan Audio.

ALIEN EARTHS takes at the science and research that is going into the quest to find out if there is life out there in the cosmos. Given that we don’t have the technology to leave our solar system and explore the far reaches of space, science must find ways to bring answers into reach through alternate means.

Lisa Kaltenegger is an astrophysicist and a founding director of Cornell University’s Carl Sagan Institute. She talks about the ways we can use our own home planet and all that we know about it’s history and present to inform the search for other life in the universe.

This book cover immediately caught my eye. I really enjoy nonfiction that brings more information about the natural world and space is always a fascinating discussion. I think the author did a good job of explaining the science she was conveying in a way that made it approachable for the non-scientific minded. She promises an “insider’s guide” to what scientists are learning from Earth, its biosphere, and some of the discoveries that have already been made.

4.5 Stars

This was a really intresting accessible introductory look into the subject matter. I thought there was a good amount of balance to try and make relatable examples of some oof the science, with a few sprinkles of pop culture to try and appeal to the general reader. I really found some of the collaborative work interesting, and the approach to finding life elsewhere needing to start with taking a look at life on Earth in order to be able to recognize it. I also that that the author had a unique approach to sexism in the scientific field. In most places I wished it dived deeper, but I understand many readers might not be looking for that. If you love space books with a focus on finding life I would certainly pick this book up.

Thank you to the author, publisher, and NetGalley for an advanced copy in exchange for an honest review.

This book accomplishes something almost impossible in science publications, it makes everything understandable to all readers without dumbing things down. With a conversational style that makes it easy to follow, Doctor Kaltenegger brings vividly to life what we know, or imagine, of other stars and planets. When someone says how they’re looking for alien life, she is not what comes to mind: a serious professional who applies the most stringent scientific methods to this search. This is not little green men, it is the chemical composition of stars and atmospheres, the position of the planets (or moons) within their system and many other clues as to the possibility of life. It is fascinating. Along the way, she explains how we know what we know, and how this field has evolved along with technology (and a lot of trial and error). She also puts everything in perspective, including one of my favorite parts, where she establishes where and when our immediate neighbors could see us. The other part that I enjoyed enormously was her finding real planets similar to the fictional ones that we all know and love (though I don’t appreciate how she ruined Tatooine for me due to a missing shadow!). The book is realistic enough that it disappointed me a little (how will we ever join the Federation if almost no one knows we’re here?) But she is also optimistic in that we live in a system and maybe someday, hopefully, we’ll expand our universe beyond our own spaceship Earth.
I chose to read this book and all opinions in this review are my own and completely unbiased. Thank you, #NetGalley/#St. Martin's Press.

Lisa Kaltenegger gives us a fascinating and comprehensible look at space and the universe. This is a subject I have always been fascinated with since reading my Encyclopedias at our home library. There are so many new information now with new planets and advanced technology that Kaltnegger summarizes the timelines and origins. It is truly fascinating and really recommend this book to someone who wants a primer in this subject and one that insipre. I sure was.

This is an easy-to-read and a very interesting book.

Thank You to St. Martin’s Press and NetGalley for providing me with an advanced copy of this book with an expected release date of April 16, 2024.

"Alien Earths: The New Science of Planet Hunting in the Cosmos" by Dr. Lisa Kaltenegger is a captivating voyage through the cosmos, where science and wonder come together. In this riveting exploration, Kaltenegger takes readers beyond our pale blue dot and contemplate the possibility of life elsewhere in the universe.

The book's premise is both profound and timely: Are we alone? For millennia, humans have gazed at the stars, pondering this fundamental question. Now, armed with cutting-edge technology, we embark on a quest to uncover the secrets of distant worlds. Kaltenegger, as the founding director of Cornell University's Carl Sagan Institute, leads us on this cosmic odyssey.

The narrative unfolds like a celestial detective story. How do we detect life over cosmic distances? What constitutes life? These questions propel us into the heart of exoplanet research. Kaltenegger deftly explains the specialized toolkit her team has assembled; a Rosetta Stone forged from Earth's history, and biosphere. Our home-world becomes a guide, revealing clues that may unlock the mysteries of alien realms.

With infectious enthusiasm, Kaltenegger introduces us to the most peculiar exoplanets. Imagine planets cloaked in oceans of molten lava, lonely wanderers adrift in the cosmic sea, and binary sunsets casting their warm glow. These are the celestial canvases where life might thrive—or where we might glimpse extraterrestrial beings gazing back at us.

The book delves into the imagined worlds of science fiction, bridging the gap between speculation and scientific reality. As we explore these distant realms, we encounter not just new continents but entire planets orbiting distant stars. Kaltenegger's prose dances between the poetic and the empirical, making complex concepts accessible to readers of all backgrounds.

One of the book's strengths lies in its interdisciplinary approach. Kaltenegger's team comprises tenacious scientists from various fields including astronomy, biology, chemistry, and more. Their collaboration mirrors the cosmic dance of elements that shape planetary environments. We witness the birth of stars, the evolution of atmospheres, and the delicate balance required for life to flourish.

The James Webb Space Telescope, poised to launch, promises to revolutionize our understanding of exoplanets. Kaltenegger's pioneering work ensures that we live in an epoch of unprecedented exploration. As we peer through the telescope's lens, we glimpse distant worlds that are potential homes for life. Perhaps, just perhaps, aliens gaze back at us, pondering their own existence.

Kaltenegger's prose sparkles with wonder, mirroring the awe we feel when contemplating the vastness of the cosmos. She navigates complex scientific concepts with clarity, never losing sight of the human desire to connect with the universe. Her writing invites us to dream alongside astronomers, to imagine the unimaginable.

This book is an invitation to join the cosmic conversation. Kaltenegger's passion infuses every page, urging us to look up, to wonder, and to seek answers among the stars. She becomes our tour guide and is a beacon illuminating the cosmic expanse.

Readers will enjoy “Alien Earths: The New Science of Planet Hunting in the Cosmos,” as it’s a captivating blend of science, imagination, and hope. Whether you're an amateur stargazer or a seasoned astronomer, this book will leave you pondering the universe long after you've turned the final page.

Thank you to NetGalley and St. Martin's Press for a temporary e-ARC in exchange for my honest review.

At this point, I've read most of major astronomy books written for a popular audience in the past six years. This is one of the best, and definitely recommended as a general introduction to how to think about astrobiology. Dr. Kaltenegger does a really good job of integrated personal stories into her science without making it too off-topic or unwieldy. If you keep up with astrobiology, this won't teach you anything new, but if you're looking to get caught up with the current research, this is the perfect introduction.

Overall, I thoroughly enjoyed Alien Earths, rating it at 4 stars, rounded up from a personal rating of 3.75. The book addresses thought provoking questions about our planet's beginnings, and other alien stars and planets that could serve as future options for hosting life. She explains the elements needed (or thought to be needed) for life to thrive, introduces the Goldilocks Zone, and even provides some fun facts and anecdotes along the way. The subjects, astrophysics, and astrobiology are both dense, but Dr. Kaltenegger does a good job of using colloquial language to ensure the content is presented so all readers can enjoy. Overall, the book progresses in a logical manner, jumping from one topic to the next with the appropriate flow and transition. While reading I did catch several typos but assume that the editor and author will address those before the book is sent for print. I would recommend this book to a friend who enjoys the topics of space exploration.

Thank you to St. Martin’s Press and NetGalley for providing me with an advanced copy of this book with an expected release date of April 16, 2024.

This engaging, easy-to-read book explores the quest to discover life beyond Earth, fueled by modern technology. Using Earth as a Rosetta Stone, it draws insights from its rich history and diverse biosphere. From exoplanets challenging our preconceptions, to science fiction’s imagined realms, this book offers a fascinating journey into the cosmos and our evolving understanding of life’s potential elsewhere.

Thanks, NetGalley, for the ARC I received. This is my honest and voluntary review.

With her new book, Alien Earths, Lisa Kaltenegger has established herself as the legitimate successor to Carl Sagan. Alien Earths is the most readable astronomy book I’ve ever read. That’s a huge compliment, but it’s well deserved. Kaltenegger, Director of the Carl Sagan Institute to Search for Life in the Cosmos at Cornell University, has written a book that is scientifically informative, exciting, and personal. As a leading figure in the search for life on other planets, Kaltenegger has told the story of that search from both the perspective of the history and progress of the scientific approach to the issue and the perspective of her own entry into the field and her approach to addressing the problem. In the course of doing so, the reader learns something of the basic science involved, the discoveries that have been made so far, and is given a vivid description of our cosmos as we currently understand it. She inserts just enough personal anecdotes to make us feel as if she’s telling us a story, not just presenting us with facts.

For an amateur, I’m reasonably well-versed in astronomy and planet science, but Alien Earths taught me a lot that I didn’t know. I learned that many of the exoplanets orbiting other stars that were discovered early are gas giants, somewhat like Jupiter, circling their stars in near orbits, close enough to cause a detectable wobble in the star. I learned that some burnt out stars continue to have planets orbiting their cold husks. I learned that small tardigrades, water animals barely large enough to be seen with the naked eye can survive in space and remain dormant for a hundred years. An Israeli moon shot that crash-landed may have dumped thousands of tardigrades on the moon, and they may be living there in a dormant state right now.

I’m a science fiction writer and I consume as much space science as I’m able to understand. One of the best things I gained from reading Alien Earths was an appreciation of how Earth has changed over the four and a half billion years it has existed and how those changes might appear to an outside observer. We think of our planet as mostly covered in oceans and continents with green vegetation, but most of us forget that it has not always been that way. The green vegetation that colors our planet wasn’t here before 750 million years ago, and the additional oxygen it helped to produce wasn’t sufficient to sustain the lives of mammals like us until 650 million years ago. There was a time in Earth’s past when it would have appeared black to an extraterrestrial observer, even a time when, because of the presence of oxygen but no plant life, the surface of the planet would have appeared red, like that of Mars. What Kaltenegger realized is that in our search for other planets that might support life, we might observe some of them at a time in their history when they resembled Earth in its distant past. She worked on developing light-spectrum “signatures” of these early stages of our planet in order to try to spot exoplanets that might be in one of these stages—perhaps a future Earth.

Thinking that our own planet is only at one stage in its progression and that it may be that only at this stage is it able to support human life, and at the same time realizing that there are countless other planets that have already passed such a stage or will only arrive there sometime in the future, so the prospect of other life in the universe is a dynamic one, changing over time, provides a certain perspective. We humans occupy not just a tiny speck of territory in a vastly large universe, but also a tiny slice of time in a vastly long universe-wide saga. Our presence on the universal stage is almost infinitely small. It’s a sobering thought. It’s also awe-inspiring, and the author manages to convey her own sense of wonder and awe at the discoveries that lead to such a perspective throughout her book. There are hints that she sees humanity’s future as not being tied to our planet, and perhaps not being tied to such a small slice of time.

Alien Earths is not fiction, it is not even mostly speculation. It is primarily science but written with the spirit and flair of a novel. It accomplishes what the best novels accomplish and that is to affect the reader’s perspective on the world and their sense of self. It does so by showing us what we know about the nature of our planet and the universe in which it and we exist. For a science fiction writer such as myself, it is full of information that fuels the imagination. For any reader it is a thrilling introduction to the stars, planets, and the cosmos.

Casey Dorman, author of the Voyages of the Delphi science fiction series: Ezekiel’s Brain and Prime Directive

A look into how new technology has allowed scientists to explore exoplanets. Analyzing how
planet Earth has evolved over the years allows scientists to apply that knowledge to other
planets. The universe is vast and there is still so much to explore and learn.
A fascinating read
#AlienAEarths #NetGalley

This is a very enjoyable look at the possibility of life on other planets, Written in an easy to understand style that makes the book particularly accessible to general readers, I never got lost as Ido with many other books about the universe

Thank you to NetGalley and the author for giving me the opportunity to review this ARC.

I found the book to be very informative and well written. The author writes in a very easily understandable manner, explaining at times complex issues in a very relatable manner. Perhaps this is a result of her experience as an educator as well as scientists. The content gives the reader a great perspective on our minuscule place in the universe and time. It also helps the reader understand the complexity of answering such basic questions as what is life, how do you find Target planets, and how would you spot life on those planets. I also found her explanation of space as a Time Machine based on distance, time and light. Overall, I found this book a great education on the topic and highly recommend it.

There is no thinner line than the one between talking down to people about science and explaining it in a way that everyone can understand. Lisa Kaltenegger wonderfully stays on the latter side in her book, Alien Earths. It is also possible that I am the lowest common denominator and it's impossible to insult my intelligence when it comes to science. No matter!

Kaltenegger tells an engaging story which revolves around a basic idea. Is there any earths out there like ours? Her answer: maybe! So what do we need the book for? Well, Kaltenegger to take the next steps to explain what are the conditions needed for those earths, what would it be like on those planets, and do we even have any indication they exist. Along the way, she gets in some good jokes and her love for this subject truly shines through.

Depending on your love of science, you may find this to be a must read or it may lose some steam by the end. While I enjoyed all of it, the concluding chapters start to feel a bit repetitive. There are also some memoir type tangents that range from perfectly placed to completely misplaced. These are small issues and the good of the book well outweighs any faults.

(This book was provided as an advance copy by Netgalley and St. Martin's Press.)

Lisa Kaltenegger’s Alien Earths is a great introductory book to astrobiology, the evolution of the universe and the possibilities of space exploration. This book wouldn’t be for someone with extensive knowledge of the subject matter, but she does a great job explaining concepts in a way that is familiar to the average person that might be curious about the potential for extraterrestrial life that would find denser books overwhelming. Even as someone with a fascination for outer space that regularly reads and listens to astronomy news, I found this helpful in the way it pulled information together. The majority of the book is about how life evolved or could have evolved on Earth, and what different circumstances could allow life to form. While I understand the concept of space and time, and how the light we see on Earth was emitted in the past from its origin, this takes on increased meaning in the search for life. Most stars observing the light from our sun are doing so from far enough away that we didn’t have the technology we do now - a time in their future. So it is for us to when we’re observing alien planets in our quest to find other life.

Several other impactful observations she makes that I want to highlight are the diversity of input in the search for life. In this she means both the value people in a variety of disciplines can contribute, and the variety of different genders, cultures, religions, etc. I found it so impressive that the head of her research team (a man) turned down her offer to go make copies of their PowerPoint presentation and delayed the presentation so he could do it himself and not put her as a woman in a position to be viewed as a secretary incredibly powerful, and a thing that often gets overlooked.

The other thing is that when you think about it and view Earth from the universal perspective and not the lowly human standing on the Earth’s surface, it really is like we’re on a spaceship hurtling through the universe and we are lucky enough that our spaceship sustains us rather well. But as any astronaut could tell you, they spend a lot of time doing maintenance to avoid crucial things breaking, something we should consider on our journey on Spaceship Earth.

Lisa Kaltenegger unveils the enigma of extraterrestrial existence and cosmic revelations. Examining Earth's evolution across a billion years, Kaltenegger simplifies the science and makes it as approachable as she can for the average Joe. The text explores Earth, Jupiter, Saturn, the Moon, and more, tackling inquiries about alien life, scientific collaboration, and the hurdles of dwelling on distant planets.

Offering insights from her role as Director at the Carl Sagan Institute, Kaltenegger emphasizes her accomplishments and envisions safe space travel. Despite the absence of visuals, the book remains accessible, catering to those intrigued by life-sustaining planets beyond our solar system.

"Alien Earths" by Lisa Kaltenegger is a captivating journey into the cosmos that feels like a modern-day exploration akin to Carl Sagan and Neil deGrasse Tyson. The endorsement by Charles Cockell, Professor of Astrobiology at the University of Edinburgh, sets high expectations, and this book certainly delivers.

Kaltenegger, as the founding director of Cornell University's Carl Sagan Institute, takes us on an absorbing exploration of the cosmos, addressing the age-old question of whether we are alone. With the technology at our disposal, she dives into the complexities of finding life beyond our planet and challenges our understanding of what life may be.

What makes this book stand out is Kaltenegger's infectious enthusiasm and her ability to make the science accessible. From exoplanets with oceans of lava to those with multiple suns in their sky, she introduces us to the extraordinary and diverse possibilities in our universe. The inclusion of science fiction elements and their proximity to reality adds an intriguing layer to the narrative.

The imminent James Webb Space Telescope and Kaltenegger’s groundbreaking work usher us into a new epoch of exploration. As a witty and knowledgeable tour guide, Kaltenegger not only expands our understanding of the cosmos but also sparks the imagination about the potential for life beyond Earth.

I’ve always been interested in space, so any time I see an interesting book on space travel or space in general, I know I have to read it. This time around, I spotted this book on space and looking at possible life on other planets. If we’re here, there has to be intelligent life somewhere out there, right? That’s what I’ve always believed, anyway! Technology has taken us a long way, but there’s only so far in space that we can see. The further away a planet is, the further back in time we’re viewing where that planet is on that adventure. It’s quite interesting, but it’s hard to tell whether or not there’s intelligent life out there because we’re looking at them in the past just as they would see Earth long in our past.

This was an excellent read. Lisa takes a lot of fascinating information and tells us about it in a way that’s easy for a non-scientist to understand. There’s a lot of interesting facts on other planets, how Earth is believed to have formed, and what is known based on scientific knowledge as it’s known today. I also really liked reading about her own journey, questions she gives her classes, and her own struggles as a woman in the science field. All in all, this was a wonderful read and I look forward to checking out anything she publishes in the future.

They say that it's proof of how well you understand something when you are able to explain it clearly. Dr. Kaltenegger can explain insanely complicated topics in a way that I could understand, even though this is an area where my science is severely lacking.
That's wonderful and amazing, but what makes this book even better is her musings throughout the book regarding her topic. I had never thought someone could dedicate their life to the possibility of other alien earths, but there are so many practical things we learn in trying to figure it out. In the end, there was a fantastic scene where she and her young daughter watched a rocket take off to go get her information. Brilliant

Great science book on the search for extraterrestrial planets and the possibilities of life on those planets. Easy to read and understand even if you don't know much about astronomy. Ms. Kaltenegger uses simple concepts to explain the science behind the search. Absolutely fascinating read. I received an arc from Netgalley but the opinions expressed are solely my own.