While moviegoers are fawning over Oppenheimer, armchair critics have spotted an interesting and subtle historial blooper. A scene set in 1945 features an American flag… with 50 stars. Of course, that's incorrect as it wasn't until 1959 that Hawaii was admitted as the 50th in the Union and President Eisenhower signed the executive order establishing the design of the new flag. The 50-star US flag was first flown the following year, on July 4, 1960.
But in another scene set in the same year , the correct American flag flies behind Oppenheimer.
One Twitter user had a theory: "I can argue that this is done intentionally as the colored scenes were from Oppenheimer's perspective, while the black and white scenes were from another. This would be a memory of Oppenheimer from his present day memory which does have 50 states on the flag."