So that’s what was in the attic. For the first time in 40 years, Amsterdam’s van Gogh museum unveiled a new painting by the master, which will be on exhibit starting on September 24. Titled “Sunset at Montmajour,” the work is believed to have been painted in Arles in 1888—and completely unknown to literature. The painting has been in the private collection of a family (after being shuttered in a Norwegian attic for years), and the museum would not release any more information due to privacy concerns. But it was brought to the museum two years ago for authentication, and researchers have been examining it ever since. It first entered the museum in 1991, but no one had recognized it as van Gogh’s work then. Whoops.