Set to launch October 23rd on a 13-day mission, Discovery will carry with it a key piece of the International Space Station, what's known as the Harmony module, a pressurized segment that's been in the works for almost a decade. This is lead shuttle flight director Rick LaBrode.
"This is a very significant flight for the continual assembly of the International Space Station, mainly due to the fact that when we bring the Harmony Node 2 module and put it in its final resting place, it's going to allow us to bring our international partner's modules on, specifically the Columbus module later this year and the Japanese modules earlier next year."
The Harmony module, known as "Node 2", was built by an Italian company and is about the size of a large bedroom, 23 feet long and about 14 feet tall. Launch package manager Steve Huning says the module is the first new pressurized component to be added to the ISS since 2001.
"Internally, Node 2 provides a pressurized passageway between the elements. It adds about 2700 cubic feet of volume to ISS. It includes internal secondary structure, four stowage racks, the six hatches. There's ten regular and two emergency lights inside Node 2 and it has portable breathing apparatus for emergencies."
Responding to a question about whether there has been continued pressure from NASA administrators to get the Harmony Module installed, Lead Station Flight Director Derek Hassman says there has been no unsafe rush to get the key segment in place.
"It's treated as the next step in the assembly sequence with an understanding that we have an end-goal out there of retiring the shuttles in 2010. I don't see any of the same type of emphasis if you will or kind of focus on just this mission. I think it's very much treated as another step in the sequence and if there's anything that we need to stop and talk about, if there's any issues that need to addressed, then I'm confident that we'll go do that."
In addition to installing the Harmony Module, astronauts will also move a major truss holding solar arrays to a new location on the ISS. Hassman says this is one of the more complicated missions, with more than just one major project.
"On this mission we're doing the Node 2 delivery and then we're taking on something that hasn't been done before, which is a detachment of a truss segment then a relocation to a different part on the space station, so I'll just say that there's a lot going on."
This will be the 23rd shuttle mission to the ISS and will include five space walks.