Endeavour, on the newly modified Pad 39-B, with the lightning towers built for the Ares rockets. Endeavour was designated as STS-400, the Launch-On-Need (LON) vehicle, in case a rescue mission needed to be launched for STS-125, Atlantis (hence, two Shuttles simultaneously on the Pads). Since no rescue mission was needed, Endeavour returned to her STS-127 designation, a mission to the ISS in June 2009. She is currently scheduled to be moved to Pad 39-A on May 30th.