CAPE CANAVERAL, Fla. – In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, NASA management waits for the launch of space shuttle Discovery on the STS-119 mission. From left are (standing) Director of NASA's Marshall Space Flight Center Dave King, Center Director Bob Cabana, Director of NASA's Johnson Space Center Michael Coats, (seated) Space Shuttle Program Manager John Shannon, NASA Associate Administrator for Space Operations William Gerstenmaier and NASA Acting Administrator Chris Scolese. Launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the space station and Discovery's 36th flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, Center Director Bob Cabana watches the brilliant launch of space shuttle Discovery on the STS-119 mission. Launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the space station and Discovery's 36th flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, Center Director Bob Cabana (with microphone) congratulates the mission management team after the successful launch of space shuttle Discovery on the STS-119 mission. Launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the space station and Discovery's 36th flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, Flow Director for space shuttle Discovery Stephanie Stilson, Assistant Launch Director Pete Nickolenko and Shuttle Launch Director Mike Leinbach check the computers for follow-up images of the launch of space shuttle Discovery on the STS-119 mission. Launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the space station and Discovery's 36th flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, Flow Director for space shuttle Discovery Stephanie Stilson (center) and Shuttle Launch Director Mike Leinbach applaud the mission management team for the successful launch of space shuttle Discovery on the STS-119 mission. Launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the space station and Discovery's 36th flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, Center Director Bob Cabana watches the brilliant launch of space shuttle Discovery on the STS-119 mission. Launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the space station and Discovery's 36th flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – In Firing Room 4 of the Launch Control Center at NASA's Kennedy Space Center in Florida, Shuttle Launch Director Mike Leinbach, Assistant Launch Director Pete Nickolenko and Flow Director for space shuttle Discovery Stephanie Stilson applaud the successful launch of space shuttle Discovery on the STS-119 mission. Launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the space station and Discovery's 36th flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Photo credit: NASA/Kim Shiflett