What the book's about...
- French astronomer Jean-Baptiste Chappe d'Auteroche
- British naval officer James Cook
- Hungarian priest Maximilian Hell (Reviewer's Note: A decidedly unfortunate last name for a priest.)
These three expeditions, as well as those of many others around the world, resulted in a collection of astronomical data which allowed scientists to map out the distance of objects within the solar system to a level of precision never before achieved. While this may seem an esoteric and purely academic concern to us today, this was of immensely practical concern to navigation at the time, because it provided ships with a more precise means of using astronomical observations to determine their current longitude location while at sea. This allowed the ships to better map out their location and courses to their destinations, resulting in notable benefits to both warfare and trade, which take the whole thing from academic concerns to things that governments care about immensely and are willing to pay immensely to support.
I'll confess that this isn't exactly my sort of book, which is why I only gave it 4 stars. It was perfectly enjoyable and, for readers who enjoy historical travelogues, I would highly recommend it. It was well written and certainly did a good job of portraying the challenges these adventurers faced.
The Science of the Book
The transit of Venus is scientifically relevant because it is possible to use this motion to calculate the distance of the Earth to the sun and, according to the book, "knowing the distance to the sun allowed scientists to locate the orbital path of every planet." These orbital paths could be calculated by applying Kepler's three laws of planetary motion.
The majority of the book is told in the form of a straight human drama about the expeditions themselves, and can be read without any deep understanding of the science or mathematics involved. However, for those who want to delve deeper into the subject, the book also contains a 10-page Technical Appendix which walks through the relevant calculations and answers the questions: "How, specifically, can one use the Venus transit to find the distance to the sun? And why wasn't there an easier way?"
To consider the significance assigned to this enterprise by the scientific community of the day, according to the book "instrument maker and popular science author Benjamin Martin wrote in 1761" (when there was another transit of Venus, only 8 years prior to the 1769 transit) that "If we make the best use of [the Venus transits], there is no doubt that astronomy will, in ten years time, attain to its ultimate perfection." [Emphasis added]
Publication Date: May 8, 2012
Publisher: Da Capo Press
- 280 pages
- 14 Chapters
- Technical Appendix (10 pages)
- Notes (27 pages)
- 4 pages of historical illustrations (11 total images) from the time period
- A 2-page map featuring the major locations discussed