New York Times Bestseller | Wall Street Journal Bestseller | Publishers Weekly Bestseller | Publishers Marketplace 2020 Buzz Book | Amazon Best Book of the Year | Longlisted for the 2022 PEN/E.O. Wilson Literary Science Writing Award Harvard's top astronomer lays out his controversial theory that our solar system was recently visited by advanced alien technology from a distant star. "Provocative and thrilling ... Loeb asks us to think big and to expect the unexpected."--Alan Lightman, New York Times bestselling author of Einstein's Dreams and Searching for Stars on an Island in Maine In late 2017, scientists at a Hawaiian observatory glimpsed an object soaring through our inner solar system, moving so quickly that it could only have come from another star. Avi Loeb, Harvard's top astronomer, showed it was not an asteroid; it was moving too fast along a strange orbit, and left no trail of gas or debris in its wake. There was only one conceivable explanation: the object was a piece of advanced technology created by a distant alien civilization. In Extraterrestrial, Loeb takes readers inside the thrilling story of the first interstellar visitor to be spotted in our solar system. He outlines his controversial theory and its profound implications: for science, for religion, and for the future of our species and our planet. A mind-bending journey through the furthest reaches of science, space-time, and the human imagination, Extraterrestrial challenges readers to aim for the stars--and to think critically about what's out there, no matter how strange it seems.

"The world's leading alien hunter" -- New York Times Magazine From acclaimed Harvard astrophysicist and bestselling author of Extraterrestrial comes a mind-expanding new book explaining why becoming an interstellar species is imperative for humanity's survival and detailing a game plan for how we can settle among the stars. In the New York Times bestseller Extraterrestrial, Avi Loeb, the longest serving Chair of Harvard's Astronomy Department, presented a theory that shook the scientific community: our solar system, Loeb claimed, had likely been visited by a piece of advanced alien technology from a distant star. This provocative and persuasive argument opened millions of minds internationally to the vast possibilities of our universe and the existence of intelligent life beyond Earth. But a crucial question remained: now that we are aware of the existence of extraterrestrial life, what do we do next? How do we prepare ourselves for interaction with interstellar extraterrestrial civilization? How can our species become interstellar? Now Loeb tackles these questions in a revelatory, powerful call to arms that reimagines the idea of contact with extraterrestrial civilizations. Dismantling our science-fiction fueled visions of a human and alien life encounter, Interstellar provides a realistic and practical blueprint for how such an interaction might actually occur, resetting our cultural understanding and expectation of what it means to identify an extraterrestrial object. From awe-inspiring searches for extraterrestrial technology, to the heated debate of the existence of Unidentified Aerial Phenomena, Loeb provides a thrilling, front-row view of the monumental progress in science and technology currently preparing us for contact. He also lays out the profound implications of becoming--or not becoming--interstellar; in an urgent, eloquent appeal for more proactive engagement with the world beyond ours, he powerfully contends why we must seek out other life forms, and in the process, choose who and what we are within the universe. Combining cutting edge science, physics, and philosophy, Interstellar revolutionizes the approach to our search for extraterrestrial life and our preparation for its discovery. In this eye-opening, necessary look at our future, Avi Loeb artfully and expertly raises some of the most important questions facing us as humans, and proves, once again, that scientific curiosity is the key to our survival.

Isaac Asimov concludes that we are not alone! Using the most up-to-date astronomical research as the backdrop for speculation, Asimov confronts the possibilities of other-worldly life head-on in Extraterrestrial Civilizations . In what will surely become one of the most provocative books ever written on the possibilities of life elsewhere in the universe, the incomparable Isaac Asimov provides chilling, hopeful, and exciting new insights. Here is astounding speculation about where the next giant step for mankind will take us. . . . Praise for Extraterrestrial Civilizations "[Isaac] Asimov holds our attention as he builds a meticulous case. We are not alone. It's just a matter of time until we know for sure." -- Miami Herald "Intriguing" -- Publishers Weekly

A funny, insightful, and self-contained guide to Einstein's relativity theory and classical field theories--including electromagnetism Physicist Leonard Susskind and data engineer Art Friedman are back. This time, they introduce readers to Einstein's special relativity and Maxwell's classical field theory. Using their typical brand of real math, enlightening drawings, and humor, Susskind and Friedman walk us through the complexities of waves, forces, and particles by exploring special relativity and electromagnetism. It's a must-read for both devotees of the series and any armchair physicist who wants to improve their knowledge of physics' deepest truths.

"Robert Zubrin is a true engineering genius like the heroic engineers of the past." -- Frederick Turner, American Enterprise Using nuts-and-bolts engineering and a unique grasp of human history, Robert Zubrin takes us to the not-very-distant future, when our global society will branch out into the universe. From the current-day prospect of lunar bases and Mars settlements to the outer reaches of other galaxies, Zubrin delivers the most important and forward-looking work on space and the true possibilities of human exploration since Carl Sagan's Cosmos. Sagan himself said of Zubrin's humans-to-Mars plan, " Bob Zubrin really, nearly alone, changed our thinking on this issue." With Entering Space , he takes us further, into the prospect of human expansion to the outer planets of our own solar system--and beyond.

A look up at the night sky reveals a treasury of wonders. Even to the naked eye, the Moon, stars, planets, the Milky Way and even a few star clusters and nebulae illuminate the heavens. For millennia, humans struggled to make sense of what's out there in the Universe, from all we can see to that which lies beyond the limits of even our most powerful telescopes. Beyond the Galaxy traces our journey from an ancient, Earth-centered Universe all the way to our modern, 21st century understanding of the cosmos. Touching on not only what we know but also how we know it, Ethan Siegel takes us to the very frontiers of modern astrophysics and cosmology, from the birth of our Universe to its ultimate fate, and everything in between.

The exploration of the first billion years of the history of the Universe represents one of the great challenges of contemporary astrophysics. This book contains the worked out lectures given at the 36th Saas-Fee Advanced Course "First Light in the Universe" by three eminent scientists in the field: Abraham Loeb, Andrea Ferrara, and Richard Ellis. The formation of the first stars and black holes, the initial mass function, feedback effects, early dust formation, the cosmic star formation history, distant galaxies, cosmic reionisation and the cosmic infrared background are the main topics treated. This book contains an accessible and up-to-date review of the field and will be useful to graduate students of astronomy, cosmologists, physicists and researchers. The topic of this book is particularly timely, as many new important observational facilities are being built, for which "first light in the universe" is one of the main science drivers.

Lectures on Astrophysics provides an account of classic and contemporary aspects of astrophysics, with an emphasis on analytic calculations and physical understanding. It introduces fundamental topics in astrophysics, including the properties of single and binary stars, the phenomena associated with interstellar matter, and the structure of galaxies. Nobel Laureate Steven Weinberg combines exceptional physical insight with his gift for clear exposition to cover exciting recent developments and new results. Emphasizing theoretical results, and explaining their derivation and application, this book provides an invaluable resource for physics and astronomy students and researchers. -- publisher's website.

The Universe in which we live is unimaginably vast and ancient, with countless star systems, galaxies, and extraordinary phenomena such as black holes, dark matter, and gamma ray bursts. What phenomena remain mysteries, even to seasoned scientists? Our Universe is a fascinating collection of essays by some of the world's foremost astrophysicists. Some are theorists, some computational modelers, some observers, but all offer their insights into the most cutting-edge, difficult, and curious aspects of astrophysics. Compiled, the essays describe more than the latest techniques and findings. Each of the ten contributors offers a more personal perspective on their work, revealing what motivates them and how their careers and lives have been shaped by their desire to understand our universe. S. Alan Stern is Director of the Department of Space Studies at Southwest Research Institute in Boulder, Colorado. He is a planetary scientist and astrophysicist with both observational and theoretical interests. Stern is an avid pilot and a principal investigator in NASA's planetary research program, and he was selected to be a NASA space shuttle mission specialist finalist. He is the author of more than 100 papers and popular articles. His most recent book is Pluto & Charon (Wiley, 1997). Contributors: Dr. John Huchra, Harvard University Dr. Esther Hu, University of Hawaii, Honolulu Dr. John Mather, NASA Goddard Space Flight Center Dr. Nick Gnedin, University of Colorado, Boulder Dr. Doug Richstone, University of Michigan, Ann Arbor Dr. Bohdan Paczynski, Princeton University, NJ Dr. Megan Donahue, Space Telescope Science Institute, Baltimore, MD Dr. Jerry Ostriker, Princeton University, New Jersey G.Bothun, University of Oregon, Eugene

In a unique effort, this book brings together, for the first time, scholarly analyses by eminent researchers of the historical, social, legal, and cultural influences on the young newcomers' lives as well as reports by practitioners in major aid organizations about the concrete work that their organizations have been carrying out.

This book grew out of the need to provide students with a solid introduction to modern fluid dynamics. It offers a broad grounding in the underlying principles and techniques used, with some emphasis on applications in astrophysics and planetary science. The book comprehensively covers recent developments, methods and techniques, including, for example, new ideas on transitions to turbulence (via transiently growing stable linear modes), new approaches to turbulence (which remains the enigma of fluid dynamics), and the use of asymptotic approximation methods, which can give analytical or semi-analytical results and complement fully numerical treatments. The authors also briefly discuss some important considerations to be taken into account when developing a numerical code for computer simulation of fluid flows. Although the text is populated throughout with examples and problems from the field of astrophysics and planetary science, the text is eminently suitable as a general introduction to fluid dynamics. It is assumed that the readers are mathematically equipped with a reasonable knowledge in analysis, including basics of ordinary and partial differential equations and a good command of vector calculus and linear algebra. Each chapter concludes with bibliographical notes in which the authors briefly discuss the chapter's essential literature and give recommendations for further, deeper reading. Included in each chapter are a number of problems, some of them relevant to astrophysics and planetary science. The book is written for advanced undergraduate and graduate students, but will also prove a valuable source of reference for established researchers.

The publication of this book is extremely timely, for the next major advances in manned space flight after Project Apollo will most likely be made in earth orbital operations. Manned exploration of the moon will certainly continue after the initial landing, but it will be performed essentially with the Saturn V launch vehicles and Apollo spacecraft developed in Apollo, especially in the early phases. Modifications to this basic hardware will increase operating capabilities to permit extensive lunar explo ration during prolonged stay times by the astronauts on the moon's surface. Manned orbital space stations have been studied for years, and NASA is already well along in development of its first attempt to provide more spacious accommo dations for astronaut-scientists in its Saturn Workshop program. While the Workshop is certainly not the ultimate space station of which our technology is capable, it is a workable, poor man's approach to the immediate need for using and expanding our present manned space flight capability without a de trimentalloss of momentum. The approach of converting a Saturn rocket stage into a manned laboratory and observatory in space is an improvisation that matches the use of the jerry-built Jupiter C back in 1958 to launch Explorer I. Let's hope that it can get the job done just as effectively.