Three spacewalks are planned to hook up Kibo and handle other space station work, such as replacing an empty nitrogen gas tank and seeing how best to clean a jammed solar-wing rotary joint.
Bill Gerstenmaier, NASA's space operations chief, said it seems like these are simple tasks.
"But when you get into the details of what's actually involved ... it's an extremely complicated mission," he said.
Besides all that work, one of the Discovery astronauts, Gregory Chamitoff, will swap places with the space station's current U.S. resident, Garrett Reisman, who will return to Earth on the shuttle following a three-month stay. Chamitoff will spend six months on the station.
NASA decided to proceed with its shuttle mission as planned just last week, even as the Russians continue to investigate April's rocky landing by a Soyuz spacecraft carrying three astronauts home from the space station.
A Soyuz constantly is docked at the ISS for use as a lifeboat in an evacuation. (Related: "Space Station Escape Options Include Shuttle, Pod" [June 15, 2007].)
Milestone Mission
Discovery's flight will be a milestone for NASA in more than one way.
It will be the tenth shuttle mission since the 2003 Columbia tragedy and will leave just ten more shuttle flights before the fleet is retired in 2010. That will mark the end of space station construction.
Discovery's fuel tank is the first to incorporate all the post-Columbia changes from the start of construction instead of later in the construction phase.
While shuttle managers expect this fuel tank to be the best one yet—with minimal insulating-foam loss—a full inspection of the spaceship's thermal skin still will be required.
That inspection will occur much later in the flight than usual. That's because Kelly and his crew won't get their inspection boom until they arrive at the space station.
The 50-foot (15-meter) laser-tipped pole was left there in March by the previous shuttle visitors—it couldn't fit in Discovery's payload bay given the size of Kibo.
Another milestone for Discovery's upcoming mission: Astronaut Karen Nyberg, the lone woman on the crew, will become the 50th woman to fly in space.
She will be rocketing into orbit just a few weeks before the 45th anniversary of the first woman in space, Soviet cosmonaut Valentina Tereshkova, and the 25th anniversary of the first American woman in space, Sally Ride.
"What I'm really looking forward to is the time when we're not counting anymore," Nyberg said.
