Heat from space shuttle Endeavour's auxiliary power units can be seen at the back of the shuttle near the tail.

Heat from space shuttle Endeavour's auxiliary power units (APUs), which provide hydraulic control, can be seen at the back of the shuttle, near the vertical tail. Endeavour landed for the final time on the Shuttle Landing Facility's Runway 15 at NASA's Kennedy Space Center in Florida, marking the 25th night landing of the Space Shuttle Program. Main gear touchdown was at 2:34:51 a.m. EDT, followed by nose gear touchdown at 2:35:04 a.m., and wheelstop at 2:35:36 a.m. On board are STS-134 Commander Mark Kelly, Pilot Greg H. Johnson, and Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and the European Space Agency's Roberto Vittori.

STS-134 delivered the Alpha Magnetic Spectrometer-2 (AMS) and the Express Logistics Carrier-3 (ELC-3) to the International Space Station. AMS will help researchers understand the origin of the universe and search for evidence of dark matter, strange matter and antimatter from the station. ELC-3 carried spare parts that will sustain station operations once the shuttles are retired from service. STS-134 was the 25th and final flight for Endeavour, which has spent 299 days in space, orbited Earth 4,671 times and traveled 122,883,151 miles. Photo credit: NASA/Tom Farrar