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. Wil...