[KevinDavis]

Shuttle commander Rick Sturckow, a 48-year-old Marine colonel who grew up on a ranch outside of San Diego, California, leads this voyage of Discovery. It will be his fourth spaceflight to the International Space Station, having been a pilot on STS-88 and -105 and commander on STS-117.

He is the first astronaut to board the shuttle this evening, taking the forward-left seat on the flight deck.

[KevinDavis]

Nicole Stott, the station-bound astronaut set to join the Expedition 21 crew living aboard the outpost, serves as Discovery's mission specialist No. 5 for the launch. The 46-year-old from Clearwater, Florida attended Embry-Riddle Aeronautical University before going to work as a structrual design engineer at Pratt & Whitney. She then became a Kennedy Space Center worker on space shuttles and station hardware.

Once at the space station, she will exchange places with astronaut Tim Kopra, who then will return to Earth on the shuttle to conclude a month-and-a-half in space.

Stott just crawled through Discovery's hatch to take the right-hand seat on the middeck.