Stock Photo - The four crew members of the Atlantis STS-135 mission pose for a picture on the spacecraft's flight deck. On the front row are NASA astronauts Doug Hurley (left) and Chris Ferguson, pilot and commander respectively. In the rear are NASA astronauts Sandy Magnus and Rex Walheim, both mission specialists. The U.S. flag pictured was flown on the first space shuttle mission, STS-1, and flew on this mission to be presented to the space station crew. It will remain onboard the station until the next crew launched from the U.S. will retrieve it for return to Earth. It will fly from Earth again, with the crew that launches from the U.S. on a journey of exploration beyond Earth orbit.