Space shuttle Discovery roars toward space as it lifts off Launch Pad 39A at NASA's Kennedy Space Center.

Atop a column of fire, space shuttle Discovery roars toward space as it lifts off Launch Pad 39A at NASA's Kennedy Space Center in Florida on the STS-119 mission. The launch was on time at 7:43 p.m. EDT. The STS-119 mission is the 28th to the International Space Station and the 125th space shuttle 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/Sandra Joseph, Kevin O'Connell