As NASA continues to juggle funding issues with the impending retirement of the space shuttle program, the agency has moved forward with officially designating Atlantis to fly the year's anticipated third mission. It will be the 135th and final flight of the 30-year shuttle era.

Atlantis' STS-135 mission is targeted for launch on June 28 from NASA's Kennedy Space Center in Florida.

Shuttle managers this week baselined the flight, which enabled the program to begin training and preparations. Originally, Atlantis' flight number was STS-335. The change to STS-135 converted the mission from a potential “launch on need” one to a formal additional flight.

“If we want to be ready to fly the mission this summer, we need to begin the work," said Stephanie Schierholz, a spokesperson at NASA headquarters in Washington, in an interview Friday. "So we are stepping ahead in full faith that it will be funded.”

STS-135's 12-day mission to the International Space Station will carry the Raffaello multipurpose logistics module to deliver cargo. The orbiter will also fly a system to investigate the potential for robotically refueling existing spacecraft, and return a failed ammonia pump module for NASA to study.

The four-member crew includes commander Chris Ferguson, pilot Doug Hurley, and mission specialists Sandy Magnus and Rex Walheim.

The two other remaining shuttle missions will also fly to the space station. Discovery's STS-133 is scheduled for launch Feb. 24, Endeavour's STS-134 for April 19.

However, Atlantis' final mission can still become a rescue mission for Endeavour if needed, Schierholz said.

NASA will continue to conduct missions on the space station through at least 2020 after the orbiters retire. The agency will rely on Russia's Soyuz spacecraft for crew transportation to the space station at least until U.S. commercial companies can provide the services.

 

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