Space Shuttle Atlantis (Orbiter Vehicle designation: OV‑104) is a Space Shuttle orbiter vehicle which belongs to NASA, the spaceflight and space exploration agency of the United States. Atlantis was manufactured by the Rockwell International company in Southern California and was delivered to the Kennedy Space Center in Eastern Florida on April 1985. Atlantis is also the fourth operational and the second-to-last Space Shuttle built. Its maiden flight was STS-51-J made from 3 to 7 October 1985.

Atlantis embarked on its 33rd and final mission, also the final mission of a space shuttle, STS-135, on 8 July 2011. STS-134 by Endeavour was expected to be the final flight before STS-135 was authorized in October 2010. STS-135 took advantage of the processing for the STS-335 Launch on Need mission that would have been necessary if STS-134's crew became stranded in orbit. Atlantis landed for the final time at the Kennedy Space Center on 21 July 2011.

By the end of its final mission, Atlantis had orbited the Earth a total of 4,848 times, traveling nearly 126,000,000 mi (203,000,000 km), which is more than 525 times the distance from the Earth to the Moon.