STS-135 was the final mission of NASA's Space Shuttle program, launched on July 8, 2011. The mission's primary objective was to deliver the Raffaello multi-purpose logistics module to the International Space Station (ISS). This module contained supplies and equipment to support the station's crew. The Atlantis shuttle carried a crew of four astronauts, including commander Chris Ferguson and pilot Doug Hurley. STS-135 lasted 13 days, with the shuttle returning to Earth on July 21, 2011. This mission marked the end of an era in human spaceflight, concluding 30 years of Space Shuttle operations.