Project Mercury was the first human spaceflight program of the United States, initiated by NASA in 1958. Its primary goal was to send an astronaut into orbit around the Earth and safely return them. The program aimed to gather data on human spaceflight and develop the necessary technology for future missions. The first successful manned flight of Project Mercury occurred on May 5, 1961, when astronaut Alan Shepard flew aboard the spacecraft Freedom 7. This mission lasted about 15 minutes and marked a significant milestone in the Space Race between the United States and the Soviet Union.