NASA's Space Shuttle Endeavour Set for Evening Launch

NASA's shuttleEndeavour is poised to rocket into space this evening carrying six spaceflyersand teacher-turned-astronaut Barbara Morgan towards the International SpaceStation (ISS).

The spaceshuttle and its STS-118 crew are set to launch spaceward at 6:36 p.m. EDT (2236GMT), with weather forecasts promising an 80 percent chance of favorableliftoff conditions.

"Itlooks like we have a very good vehicle on the pad," said NASA's launch integrationmanager LeRoy Cain. "The crew is ready. The team is ready."

In additionto Morgan, Endeavour will ferry shuttle commander Scott Kelly, pilot CharlieHobaugh and mission specialists Tracy Caldwell, Rick Mastracchio, Alvin Drew,Jr. and Dave Williams - of the Canadian Space Agency - towards the ISS.

Theastronauts plan to haul 5,000 pounds (2,267 kilograms) of cargo, a loadedspare parts platform and a new starboard-side girder to the ISS during theirplanned 11-day mission. The spaceflight could be extended three extra days if anew station-to-shuttle power transfer system aboard Endeavour performs as expected.

Endeavour'splanned launch will mark the orbiter's return to flight status after nearlyfive years following a majoroverhaul.

"Thefolks that have worked on Endeavour are just feeling super right now,"NASA launch director Mike Leinbach has said. "They are just ecstatic athaving their ship so close to launch."

NASA'sSTS-118 mission is the agency's second shuttle flight in a turbulent year thathas included a now-former astronaut's arrest and recent allegations ofintoxicated spaceflyers allowed to fly on two occasions. ?

Launchday at last

For oneEndeavour astronaut, today's launch day has been a long time coming.

Morgan, aformer McCall, Idaho schoolteacher, has waited and worked through 22 years andtwo shuttle accidents for her planned evening launch aboard Endeavor. She firstjoined NASA in 1985 as the backup for New Hampshire high school teacher ChristaMcAuliffe, the first Teacher in Space who died with six other astronauts duringthe 1986Challenger tragedy.

"I seethis more of a continuation," Morgan said of her flight as it relates toMcAuliffe's. "I think the great thing about it is that people will be thinkingabout Challenger and thinking about all the hard work that lots of folks, overmany years, have done to continue their mission."

NASA calledMorgan back into its spaceflying fold in 1998, this time as a full-fledgededucator astronaut and mission specialist. She was assigned to Endeavour'sSTS-118 flight in 2002 after training to wield its robotic arm and speak forMission Control as spacecraft communicator, or CAPCOM, but had to stand downuntil NASA's return to flight following the 2003 Columbia accident.

"It isgreat to see Barbara up there ready to fly," NASA shuttle program managerWayne Hale said before today's launch attempt. "She's been working for along time to have her time, her day on orbit."

Morgan willsit in the middle seat of Endeavour's middeck, flanked by Williams and Drew.

"I'mcertainly going to squeeze the life out of her once we get to MECO and onorbit," Caldwell said of Morgan, referring to Endeavour's planned mainengine cut-off (MECO) at the end of launch.

Spacestation assembly

Endeavour'sSTS-118 mission is NASA's second shuttle flight dedicated to ISS construction thisyear and features up to four spacewalks to attach the new Starboard 5 (S5)truss and other hardware to the station's exterior.

A smallspacer truss, S5 will serve as the bridge between the stations newly-installed starboardsolar arrays and a new pair of solar wings set to launch next year. Endeavour'screw will also deliver an external spare parts platform for the ISS and replacea broken gyroscope in the outpost's U.S. attitude control system.

"I think as an engineering accomplishmentI think it's incredibly complicated," Mastracchio said of the ISS, addingso many of its components are built among many nations without ever seeing eachone another before flight. "I don't know about you, but that is amazing tome."

NASA is broadcasting the launch ofspace shuttle Endeavour live on NASA TV. Click here for STS-118 missionupdates and SPACE.com's NASA TV feed.

• VIDEO: Teaching the Future: Teacher-Astronaut Barbara Morgan
• VIDEO: Endeavour's STS-118 Launch Animation
• Complete Space Shuttle Mission Coverage