The space shuttle Atlantis, designated as mission STS-135, was launched from Kennedy Space Center in Florida. This mission marked the end of NASA's Space Shuttle Program, which had been active since 1981.

STS-135 was a 12-day mission to the International Space Station (ISS) to deliver supplies, equipment, and experiments. The mission was commanded by astronaut Christopher Ferguson and carried a crew of four. The primary objectives were to resupply the ISS and ensure that it had enough resources to support its operations after the retirement of the space shuttles.

The decision to retire the space shuttle program was made in order to shift NASA's focus to future deep space exploration missions, such as the planned missions to Mars. After the final shuttle mission, NASA relied on Russian Soyuz spacecraft and, eventually, commercial spacecraft like SpaceX's Crew Dragon for crew transportation to the ISS.

The space shuttle program was a significant part of NASA's history, with numerous missions that included scientific research, satellite deployment, and the construction of the ISS. The retirement of the program marked the end of an era and the beginning of a new chapter in human space exploration.