Decoding the Heavens: A 2,000-Year-old Computer and the Century Long Search to Discover Its Secrets by Jo Marchant is an exploration of the history and significance of the Antikythera Mechanism (/ˌæntɪkɪˈθɪərə/ an-ti-ki-theer-ə), an ancient mechanical calculator (also described as the first known mechanical computer) designed to calculate astronomical positions. Technological artifacts of similar complexity did not reappear until a thousand years later.
Marchant approaches the mystery of the mechanism in a narrative that begins with the discovery of the Antikythera wreck in 1901 and includes a primer on the development of scuba gear in the 19th century. Throughout the book, Marchant weaves ancient history with the lives and travails of the handful of contemporary scientists who bucked conventional wisdom with their belief that the mechanism embodied technological and mathematical expertise thought to be impossible for its time. It is believed to have been built about 150–100 BC and yet the delicate bronze clockwork it embodies would not be known to Europe until the Middle Ages.
A work of caution. The story involves complicated descriptions of astronomical theory. Large amounts of detail on mechanical parts. And digressions on analytical instruments. These are all impossible to understand without drawings. I listened to the audio book. As such huge amounts of technical detail were lost. It plods along at a glacial pace. Personally, I got more out watching a documentary on the mechanism.