Ending 30 years of space shuttle flights, NASA named its final crew on Tuesday, assigning four veteran astronauts to train for a standby rescue mission that NASA hopes will turn into a bonus station cargo delivery run.

Chris Ferguson, Doug Hurley, Sandra Magnus and Rex Walheim will begin a year-long training program with no guarantee of flying again.

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“The normal training template for a shuttle crew is about one year prior to launch, so we need to begin training now in order to maintain the flexibility of flying a rescue mission if needed, or alter course and fly an additional shuttle mission if that decision is made,” NASA’s spaceflight chief Bill Gerstenmaier said in a statement.

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Since losing the shuttle Columbia crew in 2003, NASA has been preparing a shuttle and crew for a rescue flight in case a sister ship becomes too damaged during launch or while in orbit to safely return to Earth. The last official flight on NASA’s manifest is the February 2011 mission aboard shuttle Endeavour to deliver the Alpha Magnetic Spectrometer particle detector to the space station.

If that crew couldn’t come home aboard Endeavour, it would seek shelter aboard the station until Ferguson and his crew, launching aboard shuttle Atlantis, arrived in June.

NASA also is holding out hope Congress will turn Atlantis’ mission into an actual flight to deliver cargo and spare parts to the station. If approved, Ferguson and his crewmates would fly NASA’s 135th and final flight.

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NASA’s current next-to-last flight is scheduled for launch Nov. 1 aboard shuttle Discovery. The ship is due to be rolled out to the launch pad at Kennedy Space Center in Florida next week. It will carry spare parts, a prototype robot and a storage pod that will be left behind at the station.

Image: Chris Ferguson, commander of shuttle to nowhere — at the moment. Credit: NASA