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Extraterrestrial

The First Sign of Intelligent Life Beyond Earth

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Extraterrestrial

By: Avi Loeb
Narrated by: Robert Petkoff
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About this listen

 The world's most eminent scientist of space explains why he believes in extraterrestrial life

'VISIONARY' Stephen Greenblatt

Harvard's top astronomer lays out his controversial theory that our solar system was recently visited by advanced alien technology.

In late 2017, scientists at a Hawaiian observatory glimpsed a strange object soaring through our inner solar system. Astrophysicist Avi Loeb conclusively showed it was not an asteroid; it was moving too fast along a strange orbit, and leaving 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 theory and its profound implications: for science, for religion, and for the future of 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.

(P) 2021 Houghton Mifflin Harcourt©2021 Avi Loeb Astronomy Astronomy & Space Science Science Solar System Technology Interstellar

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Critic reviews

I have a lot of time for Loeb. He has a joy in conjecture and an omnivorous spirit of inquiry that are more reminiscent of 20th-century thinkers such as Freeman Dyson or Carl Sagan than most of his peers. His readiness to stake his reputation on such an unconventional hypothesis is a mark of uncommon bravery . . . [Carl] Sagan would have liked this book (Oliver Moody)
Compelling . . . The book is not so much a claim for one object as an argument for a more open-minded approach to science - a combination of humility and wonder
An astronomical Sherlock Holmes . . . You don't have to share his conviction to be impressed by the breadth of his argument
In this passionately argued, visionary book, astrophysicist Avi Loeb urges us to abandon the arrogant fantasy that we are the only sentient life form in the universe. The clues are fascinating, and still more are Loeb's arguments for what they might reveal to us about our own brilliant, blinkered, and quite possibly doomed civilization (STEPHEN GREENBLATT, Pulitzer prize-winning author of THE SWERVE)
A serious scientist makes a serious argument for the hypothesis that our solar system was visited by an object from an extraterrestrial civilization. Is the hypothesis right? Who knows. But let's try to find out! (ERIC MASKIN, Nobel laureate in Economics)
It's good to be sceptical of audacious ideas. But it's also important to be open to audacious possibilities. Loeb's sumptuously written book will provoke you to think about the possibility of intelligent life elsewhere in the universe in new and stimulating ways (SEAN CARROLL)
An exciting and eloquent case that we might have seen a sign of intelligent life near Earth - and that we should search further. World-renowned scientist and innovative thinker, Avi Loeb opens your mind to some of the most important questions facing us as humans: scientific curiosity is key to our future success (ANNE WOJCICKI, CEO and co-founder, 23andMe)
A provocative and thrilling account of the search for extraterrestrial intelligence . . . Professor Loeb asks us to think big and to expect the unexpected (ALAN LIGHTMAN, author of EINSTEIN'S DREAMS)
One of the more imaginative and articulate scientists around . . . half memoir, half soaring monologue
A persuasive scientific argument about 'Oumuamua's otherworldly origins, and delves into why his peers have been so hostile to the idea of life outside of Earth
In publishing his theory, Loeb has certainly risked (and suffered) ridicule . . . Still, it's thrilling to imagine the possibilities
Have aliens ever been to our solar system? A quick trawl of the internet will reveal any number of people who think that they have, but when the suggestion comes from a distinguished Harvard astrophysicist, maybe it's time to sit up and take notice (4-star review)
All stars
Most relevant
Great story and well thought out. First heard Avi on Lex Friedman podcast and loved it

fascinating

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This was a superb account of an event from a purely scientific point of view based on the data. no conjecture pure facts. I really enjoyed that Avi interwove stories of his life in between the more science based parts, it kept it engaging and gave it a human touch.

Inspirational stuff. A beacon of hope.

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Very interesting open minded. This guy is addictive to listen to if you have a thirst for knowledge

Compelling

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I bought this book on account of hearing Loeb being interviewed and having been fascinated by ‘Oumuamua in 2017 (if you’ve read Rendezvous With Rama by Arthur C Clarke then ‘Oumuamua will not have passed you by unnoticed!).

I’m not a scientist but the fundamental questions in this book fascinate me and I appreciated hearing more about ‘Oumuamua alongside Loeb’s personal and professional views on the bigger picture (one might even describe it as Life, the Universe, and Everything...views of a Harvard Professor).

I recently read ‘The Precipice: Existential Risk and the Future of Humanity’ by Toby Ord and these two books complement each other really well, they share common ground.

This book has been published in 2021 and I hadn’t appreciated that the search for extraterrestrial life is still regarded as a less credible career path for young academics, and that it still does not compete well for resources versus other areas of scientific discovery. I hope this book goes some way to changing that.

Brilliant read, thought-provoking, hope it inspires (and helps!) future generations of scientists

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I only bought this book as tendering for an animation project around the subject of Astrophysics and Dr Loeb’s name came up.

Well written and thought provoking. I do hope this inspires a while new era of discovery.

Amazingly thought provoking read!

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