I still can’t see it. I go outside at night and watch the stars spinning around the north star, I watch the sun come up, move across the sky, go down. On early autumn mornings in my backyard, I keep checking to see when I will get that first glimpse of the just-rising stars of Orion, knowing that, when I finally see them, winter is truly on the way. But from where I stand and watch, it’s all happening far over my head. I try to feel the earth spinning beneath my feet and to picture the globe rushing around the sun, but I just can’t.
If I had been an astronomer back when Nicolaus Copernicus first proposed that the sun, not the earth, was the center of the cosmos, I like to think that I would have immediately recognized the simplicity and elegance of this idea and intuitively known it to be correct. But I suspect the opposite. I would probably have just joined the clamor of dismissive voices that simply knew Copernicus couldn’t be right. How could he be? Every one of the senses that I use to observe the world below me and the sky around me tell me a single irrefutable fact: The earth is absolutely stationary.
Somehow Copernicus himself made the leap. How? Dava Sobel describes his life and his legacy in her enjoyable “A More Perfect Heaven,” but even she never says — because no one knows — how he first jumped to his conclusion. What we get is a delightful immersion into tumultuous times: At the beginning of the 16th century in Catholic Poland, Teutonic knights rampaged, bishops intrigued, and Lutherans threatened. Five hundred years later, records of many of Copernicus’s quotidian public interactions are remarkably well preserved, and Sobel weaves them together to follow Copernicus while he leads an almost ordinary life as a church canon, a physician and a bureaucrat. He oversees peasants’ land transactions, attends to bishops, defends against marauders, and writes a treatise on monetary policy. In addition to his official duties, however, he also observes the skies, charting the positions of the sun, moon and planets, and precisely refining the startling new heliocentric theory of the universe that he has been working on since his early 30s. By age 65, Copernicus has completed much of the work on his theory, but, perhaps frightened of the likely consequences of publication, seems to have become resigned to keeping the details to himself.
All this history is just the background for the heart of Sobel’s book: the meeting of the aged Copernicus with the young German mathematician Georg Joachim Rheticus, who had heard of Copernicus’s ideas and traveled to Poland for a first-hand account. Rheticus stayed, helped Copernicus finish his treatise and, four years later, shepherded it through its first printing.
What did Rheticus say to convince the reluctant Copernicus to risk the ridicule and censure that the book surely would (and did) receive?
Once again, no one knows. But this moment in astronomical history is so clearly pivotal and dramatic that Sobel turns to dramatic fiction to help capture how it might have been. The center of her book is a two-act play imagining the first meeting of the two men, the reawakening of Copernicus’s desire to explain his ideas to the world, and the final rush to print. The play closes as Copernicus, lying on his death bed, receives the first printing of “On the Revolutions of the Heavenly Spheres” and promptly expires, which seems a melodramatic flourish except that the event actually appears in the historical record.
Though he didn’t live to see it happen, Copernicus’s book was both scorned and admired, sometimes by the same person. Even if setting the earth spinning was too much for some, his meticulous observations and tabulations of the positions of the planets were such an improvement over the 1600-year-old work of Ptolemy that had been, up until then, the standard, that no one who cared about the skies could afford to ignore him. And a lot of people cared about the skies, from court astrologers eager to know precise celestial positions, to the Catholic Church, which declared “On the Revolutions” suspended until corrected but still needed its calculations to date Easter more precisely.
In a coda, Sobel directly traces the influence of Copernicus by describing inscriptions and annotations made by later astronomers in their copies of his treatise. Galileo hand censored his own copy, as the church required, perhaps to keep himself out of trouble (it didn’t seem to have helped). Kepler inked in tiny questions at crucial points and may have even received a little inspiration for his great discovery about the shapes of planetary orbits when he read a one-word marginal note someone else had written in Greek: “ellipse!.” Halley had a copy lying around while he was trying to connect the orbit of the comet that now bears his name. Hubble had one nearby as he proposed the expansion of the universe.
We’ll never know precisely how Rheticus convinced Copernicus to finally set it all in print, but, as Sobel shows, we certainly owe him gratitude, for these manuscripts are treasures of our world, tracing our first steps out into an understandable cosmos.
A MORE PERFECT HEAVEN
How Copernicus Revolutionized the Cosmos
By Dava Sobel
Walker. 273 pp. $25