Galileo was looking through a new telescope in 1610 when he noticed several bright objects flickering around the planet Jupiter. His discovery of moons around Jupiter was a huge blow to the idea that everything in the universe is in the same place.

The theory of a sun-centered solar system was proved thanks to the finding.

The University of Michigan Library describes a manuscript related to the discovery as one of the greatest treasures in its collection. The top is a draft of a letter signed by Galileo, and the bottom is a sketch of the moons around Jupiter.

If it were real, it would be. After Nick Wilding, a historian at Georgia State University, uncovered evidence suggesting the manuscript was a fake, the library investigated and determined that he was correct.

Donna L. Hayward, the interim dean of the university's libraries, said in an interview that it was "gut-wrenching" to learn Galileo wasn't actually a Galileo. Since the purpose of a library is to expand knowledge, the university decided to be transparent about its findings and announce the forgery. It's counter to what we stand for to clean it under the rug.

The author of a biography of Galileo found evidence that a Galileo work was a fake. While looking at an online image of the Michigan manuscript, he became suspicious. The letter forms and word choices seemed odd to him, and even though the top and bottom were written months apart, the ink seemed remarkably similar.

It jumps out as odd. There are two documents on a single sheet of paper. It's all the same brown.

Wilding, who teaches a summer course on forgery at the University of Virginia, discovered that there was no record of the Michigan document in Italian archives. After the death of the Detroit businessman who bought it, it was bequeathed to the university. In May, Wilding sent an email to the library asking for more information and requesting an image of the document's watermark, which can be seen when held to the light.

The curator at the library's Special Collections Research Center felt a sinking sensation when he saw Wilding's name on the email. He took a picture of the document's watermark, a circle with a three-leafed clover and the letter B.

The provenance information raised red flags, as the auction catalog said it had been verified by the late Cardinal Pietro Maffi. The documents were given to him by a notorious 20th century counterfeiter in Milan.

As soon as I heard the word 'Nicotra,' I got the feeling of a pony.

Amy Crist, the library's book and paper conservator, found that the ink and paper were consistent with the period and gave him hope that the document was legit.

The Galileo document at the Morgan Library & Museum in New York had a slightly different watermark than the one found in the Galileo document. The document was almost exactly the same as a letter Wilding found in Italian archives. He contacted them with his concerns.

Wilding found a reference work called "The Ancient Paper-Mills of the Former Austro-Hungarian Empire and Their Watermarks" with information on paper from the city. The Morgan and Michigan had copies. The answer was in the Morgan Library's department of literary and historical manuscripts.

The document in the reference book that dated to 1790 matched the document on the Morgan letter. It is highly unlikely that Galileo could have used the paper more than 150 years earlier because no other document with a "AS/BMO" watermark appeared before 1770.

It was a sad day for the man. He thought that was the end. The person is called a checkmate.

He felt responsible for not knowing about Michigan's document earlier. He lamented that he hadn't done what Galileo was actually doing.

Palmer said in an interview that he accepted Wilding's findings that the 1607 letter was not a genuine Galileo and that the library would update its catalog to state that it was once attributed to Galileo.

The revelation of forgeries doesn't change Galileo's discovery. The discovery that had appeared to show the scientist wrestling with his observations in real time was eliminated. The confusion of the forger, not the scientist, may be to blame for the mystery surrounding Galileo's sketches of the Michigan document. Wilding said that they had a simpler account. There is no need to explain the argument that doesn't fit.

The staff of the Michigan library is considering how to use the object to examine the methods and motives behind forgeries, which could make it the centerpiece of a future exhibit or symposium.

The forgery is a great one. This is a more interesting item due to the discovery.

The Italian is said to have started selling fake letters and musical manuscripts to support mistresses. An investigation into a dubious Mozart manuscript led the police to raid his Milan apartment in 1934, finding a virtual "forgery factory."

There are more than one false document in the collections that are waiting to be discovered.

Hannah Marcus, an associate professor in Harvard's department of the history of science, said there are more forgeries out there. She thinks Wilding has done a good job exposing fakes. She said that not everything has to be read with suspicion.