As Pirs linked up to the Zvezda module, Expedition Three Commander Frank Culbertson said, "We really felt that", describing the new component settling into its new home.
The docking went according to plan, with the automated docking system controlling a Progress-style instrumentation and propulsion system attached to the rear of the Pirs compartment itself. The 16-foot-long, 8,000-pound module approached the station from below and behind, beginning its automated docking sequence shortly after 5:30 p.m. About 20 minutes later, the station's thrusters moved it to the proper orientation for docking. The station's large solar array wings were positioned to eliminate contamination from the jets on Pirs as it made it final approach.
After the probe-and-drogue docking system completed capture of the incoming module and pulled the two spacecraft together, 12 active latching hooks were driven to their closed position, locking the module securely in place.
After docking, the Expedition Three crew checked to make sure there was a good seal between the station and its new module, then began to equalize pressure between the two craft prior to the first opening of the hatch to Pirs, which was scheduled later this evening. The aft instrumentation and propulsion system locked onto the docking compartment itself will be jettisoned next month to set the stage for spacewalks by the crew to install and activate key systems for the compartment's future operation. Pirs, which is the Russian word for pier, was launched on a Soyuz rocket at 6:35 p.m. CDT Friday. The new Russian component is an additional docking port for future Russian vehicles arriving at the station, an added stowage area and an airlock for the Russian segment. Three space walks are to be conducted in October and November from Pirs by the Expedition Three crew - two by Pilot Vladimir Dezhurov and Flight Engineer Mikhail Tyurin and one by Culbertson and Dezhurov - to electrically mate the Docking Compartment to Zvezda and install more equipment on the outside of the module.
The International Space Station (ISS) is orbiting at an average altitude of 240 statute miles (385 km).