STS 134 (NASA) STS 134 refers to the final mission of Space Shuttle Endeavour, launched by NASA on May 16, 2011. This spaceflight, lasting 16 days, was part of the Space Transportation System (STS) program and its primary objective was to deliver scientific payloads to the International Space Station (ISS) and to perform close-range studies of the Moon using the Alpha Magnetic Spectrometer-2 (AMS-2). The mission also marked the end of NASA's space shuttle program, which had been in operation for over three decades. This event highlighted the transition phase from reusable winged spacecraft to newer means of human spaceflight exploration.