The first U.S. atom bomb explodes during a test in Alamogordo, N.M., July 16, 1945. The cloud went 40,000 feet in the air, as viewed by an automatic camera six miles away from the site. A new film on J. Robert Oppenheimer's life and his role in the development of the atomic bomb as part of the Manhattan Project during World War II opened in theaters on Friday, July 21, 2023. AP Photo