DETROIT — A Galileo Galilei document that has been one of the University of Michigan library's treasures turned out to be a forgery, a development that an expert on the famed 15th-century Italian astronomer has praised the university for acknowledging.
The fake was discovered by Nick Wilding, a history professor at Georgia State University who had uncovered other counterfeit Galileo works. He contacted UM officials in May about his concerns about Galileo's supposed original notes on the orbits of Jupiter's four moons. Galileo invented the telescope that helped him discover Jupiter's moons.
Wilding reached out to the UM's special collections library and curator Pedro Alvarez, who provided materials that led to the confirmation that the notes, previously thought to be the first observational data on objects orbiting a celestial body other than Earth, were a forgery.
After an internal investigation, the university acknowledged that what it called "the Galileo document" is "a 20th-century fake." It will no longer be "considered one of the jewels of the library’s collection," and its place in the collection will be reassessed with an eye toward keeping it for research in "the arena of fakes, forgeries, and hoaxes, a timeless discipline that's never been more relevant," according to the UM library's statement.
"This document came to the University of Michigan in 1938," Alvarez said. "I inherited an artifact already, sort of, venerated by the scholarly community, venerated institutionally."
Despite this, Alvarez said he still feels responsible for not detecting the forgery.
"For me, the main learning experience is that we have to ask questions all the time. We cannot accept, you know, what other people told us," Alvarez said. "We have to think about how we acquire material, and from whom."
Wilding said the UM's handling of the situation was exemplary and that he appreciated how transparent university officials were.
"No special collections wants someone like me to come along and say, 'I think, you know, that really precious thing might be worthless,'" said Wilding, who in 2012 found evidence that a special edition of Galileo's "Sidereus Nuncius," or "Starry Messenger," a book touted as the find of the century, was a fake.
"There's no shame on this," he added about the UM document. "It was a damn good forgery."
Albert Van Helden, a professor of the history of science at the University of Utrecht in the Netherlands, has published several books and papers on Galileo, some of which cited UM's document.
"The forgery discovery does little to change the story about the discovery of Jupiter's moons," Van Helden said in an email. "What it does do is teach historians once again not to take the authenticity of their manuscript sources for granted — especially not those ascribed to famous people."
Alvarez said there are no plans to review other documents in the university's special collections library, as there are too many and too few resources.
Suspicions first surface
The forged Galileo manuscript has been one of the UM library's treasures since 1938. It is a one-page document containing a draft of a letter sent to the Doge of Venice in 1609, explaining the uses of a telescope Galileo had built and notes about the orbits of Jupiter's moons.
Galileo's observations with the telescope led him to support the theories of 14th-century astronomer Nicolaus Copernicus, who rejected that the Earth was the center of the universe and advocated the universe revolved around the Sun.
Galileo's celestial observations were presumed to have been documented using the telescope and thought to have been written several months after the letter was drafted.
UM's Alvarez said his job as the library's special collections curator is to purchase manuscripts and books from the Middle Ages through the 18th century. To ensure that the university doesn't buy forged documents, he only deals with trusted vendors and always investigates each item's provenance.
But the Galileo document was donated to the University of Michigan in the late 1930s, so Alvarez inherited the purported notes after they had been initially vetted.
Wilding was doing research for a biography on Galileo and was well aware of the UM's document. He had even cited it in previous articles.
"It's a beautiful document, and it's all on one page as well, so it photographs really nicely," Wilding said. "It's been reproduced plenty of times, it's almost something you don't notice anymore."
But Wilding said he began to notice contradictions in satellite positions and other information when comparing the Ann Arbor document to manuscripts and logbooks of Galileo's notes in the National Library in Florence, Italy.
Historians previously said the UM document was a first draft that Galileo later copied into his logbooks. Contradictions and errors were explained as mistakes Galileo made in dating the materials, according to Wilding.
"I just thought, 'I don't understand what it is that I'm looking at really,'" he said. "'So maybe that's not my problem.' Maybe that's the document's problem."
"I started noticing things like, it looks as though it's written in a single sitting. The ink has a kind of consistency of color," Wilding said.
Since Galileo had to make his own ink and cut new quills frequently, day-to-day variations in ink color and writing are very noticeable in his documents, the Georgia State professor said. The consistency in the writing and ink used for the letter draft at the top of the UM document and the notes on the bottom, presumably written months apart, struck Wilding as odd.
Prior to being donated to the UM in 1938 by manuscript collector Roderick Terry, the document was purchased at an auction in the United States in 1934. At the auction, a note written by Cardinal Pietro Maffi, head of the Vatican observatory in the 1920s and a collector of Galileo's writings, authenticated the document. Maffi had compared the document with his own Galileo writings and found them to be similar.
Maffi's Galileo documents were given to him by Tobia Nicotra, an infamous forger in the 1930s of not only Galileo's work but manuscripts by Wolfgang Amadeus Mozart, Richard Wagner and other classical music composers, Wilding said.
"Cardinal Maffi compared it (the University of Michigan's document) to his documents and they look the same, and I figured well, probably because they were written by the same person — Nicotra," Wilding said. "To me, it seemed pretty damning, but not enough to actually say 'this is fake' with any degree of certainty."
The forgery's smoking gun
Wilding then reached out to UM's Alvarez, who provided him with an image of the watermark on the university's Galileo document, which contained two monograms, AS and BMO.
"I have a fair degree of familiarity with the paper that Galileo used, and it didn't look right," Wilding said. "It looked like the kind of watermark that I've only seen on 18th-century letters and books."
He eventually found that BMO signified the paper was made in Bergamo, a city in Italy. Denoting the source of the paper as Bergamo using the BMO monogram only became a practice in the second half of the 18th century.
Wilding found the same monograms on a letter by Galileo in the Morgan Library in New York. Further investigation into the Morgan document's watermark revealed that it could be precisely dated to 1790, confirming that both it and UM's document were forgeries.
"Presumably what happened is the forger was going through library books, cutting out the endpapers, which are the protective non-printed papers put into old books," Wilding said. "Wherever he was getting his paper, he was using stocks of Bergamo paper."
Without the hard proof of the watermark, Wilding said he would have had suspicions but lacked the confidence to air them. While the Galileo forgery was good, particularly the handwriting, Wilding said he noticed some red flags such as the lack of contractions and incorrect shorthand abbreviations.
"As soon as you know that the whole thing is an anachronism, the page the thing is written on is 200 years too late, then you can start spotting the other stuff," Wilding said.
———
