• World

Galileo’s Moon View

4 minute read

For those with a passion for rare books, delving into an original work of Galileo has always offered unparalleled insight. There is no more immediate way to bring his inquisitive spirit to life than to view an original printing of Sidereus Nuncius (Starry Messenger, 1610), in which he describes the contours of the moon as seen through his newly invented telescope, or to marvel at a first edition of Dialogue Concerning the Two Chief World Systems (1632), his challenge to the Ptolemaic view of an Earth-centered universe.

But what if we could actually see this founding father of modern science in the throes of discovery? Horst Bredekamp, a professor of art history at Berlin’s Humboldt University and author of a new book entitled Galilei der Künstler (Galileo the Artist), says we can. He and other experts in Germany and Italy have concluded that five watercolor sketches of a mustard-colored moon drawn in a printer’s proof of Sidereus Nuncius are by Galileo’s own hand. The first printing of the legendary treatise included copper engravings of the moon believed to be based on different (now lost) Galileo sketches. But the copy studied by Bredekamp, which was recently unveiled in the city of Padua, Italy, where Galileo made his initial lunar observations, includes the astronomer’s only known original drawings of the moon. They are the direct record of the budding astronomer, then 46, peering through his precious new telescope and sketching what he saw directly onto the page. “You can see that they were done quickly, but with incredible precision,” says Bredekamp. Galileo’s renderings revealed the moon’s shadows as craters, hills and valleys. Identifying such Earthlike topography in a heavenly body was an important step toward the conclusion that later put him at odds with the Catholic Church: that Earth was not the center of the universe.

The drawings, which historians say may be the most important Galileo find in more than a century, are in a specimen of Galileo’s volume that had long been secreted away in the collection of an anonymous South American. At the request of New York-based rare-books dealer Richard Lan, who now owns it, Bredekamp and his associates examined the drawings over the course of two years, dating paper and ink and comparing brushstrokes with other known Galileo sketches. Bredekamp believes that Galileo, who was overseeing the printing of Sidereus Nuncius, drew the moons on the pages of a proof of the work where copper engravings would subsequently be added for the first edition. Lan, who won’t divulge further details about the previous owner, says the original drawings make the specimen “an acquisition of a lifetime,” since “so little related to a personal aspect of Galileo is on the market.” The book will go on show at his Manhattan gallery for a week in September, says Lan, and will carry a price tag of at least $10 million. He notes that past Galileo volumes have sold there for anywhere from $5,000 to $1 million.

Though drawings featured prominently in Galileo’s work, his role as artist and draftsman has until now been little more than a footnote in accounts of his life. The native of Pisa, Italy, born in 1564, would eventually be celebrated (and castigated) for his controversial celestial discoveries, his advocacy for an experiment-based approach to the natural world, and his complicated and combative relationship with the Church. Yet his artistic bent was central to his life, too. William Shea, who holds the Galileo Chair in History of Science at the University of Padua, notes that as a teenager the future scientist received comprehensive training as a draftsman, and would eventually count prominent Renaissance artists and architects among his best friends. Late in life, Galileo told his assistant that if he could have pursued any profession, he would have been a painter. “There are so many official documents that are used to recount Galileo’s life,” says Shea, who has penned several Galileo biographies. “But he is at his most moving when he’s talking to artists.”

Bredekamp, a scholar of both art history and the history of science, says this latest find shows vividly how art and science worked together in Galileo’s mind. “It’s not that Galileo used drawing just to illustrate the ideas he had already discovered, but that through the movement of his hand he became aware of what he was seeing,” says Bredekamp. “Ideas come through drawing.” That is something any doodler knows well. But few drawings have ever yielded ideas as revolutionary as those of Galileo.

More Must-Reads from TIME

Contact us at letters@time.com