STS-134 was a Space Shuttle mission to the International Space Station (ISS) flown by Space Shuttle Endeavour. The mission launched on May 16, 2011, and was the thirty-fifth and final shuttle mission to visit the ISS. The primary objective of the mission was to deliver and install the Alpha Magnetic Spectrometer (AMS), a particle physics experiment that would search for evidence of dark matter and antimatter, and to perform maintenance and repair work on the station. The mission also included the delivery of supplies and equipment to the ISS and the rotation of the crew of the ISS.
The STS-134 crew consisted of six astronauts, led by Commander Mark Kelly. The crew also included Pilot Gregory H. Johnson and Mission Specialists Andrew Feustel, Michael Fincke, Greg Chamitoff, and European Space Agency astronaut Roberto Vittori.
During the mission, the crew of Endeavour successfully delivered and installed the AMS on the ISS and delivered more than 8,000 pounds of supplies and equipment to the station. They also performed maintenance and repair work on the ISS and rotated the crew of the ISS, bringing back the Expedition 26 crew and delivering the Expedition 27 crew to the station. The mission included four spacewalks to perform maintenance and repair work on the ISS.
The STS-134 mission was considered a success and helped to further the scientific research capabilities of the ISS. It marked the final mission of the Space Shuttle program and the end of an era in space exploration.