NASA's final shuttle mission, known as STS-135, took place in July 2011. The mission was carried out by the Space Shuttle Atlantis, which launched on July 8, 2011. Its primary objective was to deliver supplies and equipment to the International Space Station (ISS) and to bring back experiments and materials from the ISS. During the mission, the crew of four astronauts successfully completed their tasks, including the delivery of the Raffaello multipurpose logistics module. After spending 12 days in space, Atlantis returned to Earth on July 21, 2011, marking the end of the Space Shuttle Program that had been in operation since 1981.