Decoding the Heavens: A 2,000-Year-Old Computer--And the Century-Long Search to Discover Its Secrets

Having read a review of this book in SCIENTIFIC AMERICAN I could do no less than read it. It is an entirely fascinating tracing of history through guesses, principles of mechanics, the workers in scientific theory and their dogged pursuit of the how and why of the Antikythera mechanism. It is a lovely book from first to last.

This book traces the history of the antikythera mechanism and the ultimate decoding of it. It is a fascinating read. It feels like reading a detective novel as the researchers uncover its secrets. There is also a wonderful cast of ancient characters,

In 1900 an ancient shipwreck was discovered off the coast of the Greek island of Antikythera. Divers quickly brought up statues and other readily recognizable pieces, along with, almost as an afterthought, a strange lump of something metallic which at first seemed worthless. Then startled archaeologists and scientists noticed gears and cogs and realized that something far more interesting than any statue had been uncovered. The Antikythera mechanism was to perplex and intrigue investigators throughout the twentieth century and into the twenty-first. Jo Marchant, a science writer for Nature and other scientific journals, has the gift of writing clearly and excitingly about subjects which might seem impenetrably obscure to laymen. Decoding the Heavens is her account of the long process of determining what the Antikythera Mechanism was designed to do, how it actually functioned, and who might have been its original designer. She is able to give life to the succession of highly intelligent and sometimes irascible and eccentric investigators who spent much of their lives on the Antikythera Mechanism. She is also able to explain the complexities of modern technological developments which enabled the investigators to finally unravel the secrets of the Mechanism. I really enjoyed Decoding the Heavens, particularly the parts in which Marchant speculates on who might have been the Mechanism's original designer. While I wish a map of the eastern Mediterranean had been included to help pinpoint Antikythera, Rhodes, Corinth, Syracuse, and the many other places mentioned in the book, I have no hesitation in recommending this book to anyone interested in the Greek and Roman world or in ancient and modern technology.

This is a book that contains just about everything: adventure, exploration, archaeology, ancient technology, detective work, science, astronomy, ancient history and modern technology pushed to its limits. The author has done an excellent job of recounting the history and ongoing saga of the Antikythera mechanism by weaving all of the above ingredients together, along with plenty of excitement, intrigue, frustration and some deception. The important roles of the key people who have been involved with this device since its discovery at the turn of the twentieth century are all very prominently described. Unfortunately, a few errors have crept in. On page 30, reference is made to "0 AD". This must surely be a misprint since there was never a year 0 (let alone 0 AD). On page 99, some statements about Rutherford and Einstein are incorrect. Rutherford never split the atom nor did he use accelerators (he used alpha emitting radionuclides to probe the structure of the atom). And Einstein did not rely on experimental results to develop his famous mass-energy equivalence formula; he developed it on purely theoretical grounds as part of his Special Theory of Relativity published in 1905. On page 134, ten lines from the bottom, thulium-170 has one more neutron than thulium-169, not an extra proton as stated here. On page 227, near the middle, a description of X-ray production is given. However, what is described is the production of fluorescence X-rays. These are not energetic enough for X-Tek's purposes. The much more energetic X-rays that were used are bremsstrahlung X-rays; these are produced directly from the high energy electrons in the initial beam and are thus much more energetic and penetrating. Despite the fact that these errors may be misleading and occasionally annoying, they do not detract from the main essence of this fascinating story. For that reason, I still gave the book five stars. The writing style is clear, friendly, accessible and very engaging. This book can be enjoyed by anyone, but ancient history/technology/astronomy buffs will likely relish it the most.

The "Antikythera Mechanism" has baffled archeologists and scientists for more than a century. Discovered in an ancient Greek shipwreck in 1901 near the Greek island of Antikythera, between Kythera and Crete, it is the first known mechanical computer in human history. It is rumored to have been used to calculate astronomical positions, and probably dates to the first century before the Common Era (BCE). The "Antikythera Mechanism" was remarkable in that its many gears betray a complexity not found elsewhere in the ancient Mediterranean world. Not until the high Medieval era would technological artifacts of similar complexity be found. With more than 30 gears, there is some difference of opinion on the number, it had the potential to enter a date and the mechanism could calculate the position of the Sun, Moon, or the other planets. It also had the capability to predict lunar and solar eclipses. Jo Marchant, a well-known journalist and the editor of "New Scientist," has written a fascinating account of the discovery of this remarkable relic, its reconstruction, and the process of discovery of scientists gradually coming to understand its use. Made of bronze and found in pieces on the sea floor, it took considerable time to put it back together and to get it to work. Hundreds of scholars have investigated the "Antikythera Mechanism," and employed high-technology analysis to understand the artifact. Even so, it took a century to unlock its secrets. Michael Wright, curator at the Science Museum in London, worked for more than two decades to build a working model of the artifact, using only tools and methods known to have been available in ancient Greece. Roger Hadland, an engineering entrepreneur, invested heavily to develop high-technology instruments, including a special X-ray machine, to image the object. These and others contributed to a long-term effort to learn the nature of this remarkable ancient machine. Part detective story as well as a record of remarkable and diligent scientific investigation, "Decoding the Heavens" is a wonderfully researched and written exploration of efforts in the modern era to learn more about activities of the ancient world.