Space Shuttle Solid Rocket Booster design or replacing them altogether with liquid "flyback" boosters using either Atlas V or Delta IV EELV technologies. The 5-segment SRB, which would have required little change to the current shuttle infrastructure, would have allowed the space shuttle to carry an additional of payload in an International Space Station-inclination orbit, eliminate the dangerous "Return-to-Launch Site" (RTLS) and "Trans-Oceanic Abort" (TAL) modes, and, by using a so-called "dog-leg maneuver", fly south-to-north polar orbiting flights from Kennedy Space Center. After the destruction of "Columbia", NASA shelved the five-segment SRB for the Shuttle Program, and the three surviving Orbiters, "Discovery", "Atlantis", and "Endeavour"
Space Shuttle Endeavour 299 days in space. During "Endeavour's" last mission, the Russian spacecraft Soyuz TMA-20 departed from the ISS and paused at a distance of 200 meters. Italian astronaut Paolo Nespoli took a series of photographs and videos of the ISS with "Endeavour" docked. This was the second time a shuttle was photographed docked and the first time since 1996. Commander Mark Kelly was the last astronaut off "Endeavour" after the landing, and the crew stayed on the landing strip to sign autographs and pose for pictures. STS-134 was the penultimate space shuttle mission; STS-135 was added to the schedule in January