Shuttle Endeavour docked to the infant International Space Station in December 1998 as seen in top photo. Columbia will still retain its internal airlock shown in bottom view, which also shows the payload bay through the open airlock hatches. Photos: NASA and Spaceflight Now

Will Columbia ever get to visit the International Space Station, the next chapter in the human exploration of space?

That is a question that does not yet have an answer.

Presently, NASA can't use Columbia because of its extra weight. Even though it will shed some pounds in Palmdale, the shuttle still will be too heavy to lift the massive sections of the station into the high orbit needed.

However, the space agency is leaving the door open to send Columbia to the outpost for other potential reasons, and any weight saved during this tune-up just adds to the possibility of the shuttle flying to the station.

Boeing is currently completing some provisions to allow the shuttle to travel to ISS, such as "scarring" the shuttle for possibly installation of a docking port to connect with the station and other electrical, structural and communications enhancements.

"We are laying in some wiring with minimal supporting structure and plumbing so that in the event a decision was made to get (Columbia) ready for ISS missions, we could do so a bit faster by not having to access certain areas to accomplish what we're currently doing."

Columbia, however, still will not be outfitted with a new external airlock in the payload bay like its sisterships, which is needed for space station missions. Columbia is retaining its old internal airlock, keeping the 60-foot long payload bay empty for any large cargoes that need a shuttle ride into space.