Galileo confirmed as author of pseudonymous 17th century astronomy text
Enlarge / Portrait of Galileo Galilei by Justus Sustermans, 1636. Uffizi Museum, Florence. (credit: Public domain)
In August, we reported that a letter presumably written by Galileo Galilei-part of the collection of the University of Michigan's library-was actually a forgery, along with a similar document in the Morgan Library in New York City. Now that investigation has led to another discovery. An Italian historian has concluded that Galileo authored a 17th century treatise on astronomy under a pseudonym.
The Michigan letter purported to be a draft of an August 24, 1609, letter that Galileo wrote to the doge of Venice describing his observations with a telescope (occhiale) he had constructed. (The final letter is housed in the State Archives in Venice.) But Georgia State University historian Nick Wilding became suspicious of the manuscript's authenticity while working on a biography of Galileo. Wilding has exposed Galileo-related forgeries in the past, most notably a copy of Sidereus Nuncius in the possession of a New York City rare-book dealer.
Michigan's conservation laboratory determined that the ink and paper of its manuscript were consistent with the period when Galileo made his observations, but any hope of authenticity was dashed after Wilding's investigations into the watermark. It matched documents dating back to 1790-150 years after Galileo made his discoveries.