The launch of the STS-118 mission is scheduled for August 7. It will be the 22nd flight to the International Space Station (ISS) and the first flight for Endeavour since 2002.
The NASA spokeswoman said the crew would start training at the Kennedy Space Center on Wednesday and conduct a simulated launch countdown with the launch team on Thursday.
Endeavour, which has been modernized and equipped with a new system designed to let the shuttle use electrical power from the space station, will deliver a new truss segment, a Spacehab module, and an external stowage platform to the ISS, which is planned to be completed by 2010.
NASA said that during an 11-day mission the U.S. astronauts would conduct three space walks. An electrical boost from the space station could allow the mission to be extended for three extra days, and an additional spacewalk could be added.
U.S. Astronaut Scott J. Kelly, who is also a naval pilot, will lead the seven-person crew of STS-118.
NASA said the mission would mark the first space flight of an "Educator Astronaut," whose role is to "help lead NASA in the development of new ways to connect space exploration with the classroom, and to inspire the next generation of explorers, while ensuring a successful mission."
Mission specialist Barbara Morgan, who joined the NASA Teacher in Space Program in 1985, has been waiting for 22 years to get a chance to see the Earth from space.
A teacher-turned-astronaut, Morgan was originally selected among 11,000 candidates to be Christa McAuliffe's backup in the 1986 Challenger mission. After a lift-off accident, which killed McAuliffe and six other astronauts on board the space shuttle, Morgan returned to teaching in Idaho.
In 1998, she was selected by NASA as a mission specialist and reported to the Johnson Space Center.
Morgan, 55, who has most recently served in the Robotics Branch of NASA's Astronaut Office, will operate the shuttle's robotic arm during the upcoming mission.
