Mission Control Center, Houston, Texas

HOUSTON - Focus today aboard the International Space Station and space shuttle Discovery was on spacewalk preparations and tests of the urine recycling unit - part of an overall system designed to regenerate waste water and urine into drinking water as the complex prepares to increase its crew size from three to six.

Station Commander Mike Fincke spent much of the day working with the Urine Processing Assembly now that it has a new distillation assembly delivered by Discovery's crew. Initially the system showed a lower than expected flow rate when attempts were made to fill the reservoir tank, but after a tank swap, the tank was filled.

A second “dry spin” of the unit is underway with a microphone strategically placed near the new Distillation Assembly to allow engineers on the ground to collect sound data in order to compare with that gathered before launch during the unit's ground certification testing. Fincke and former Flight Engineer now shuttle Mission Specialist Sandy Magnus reported that during the first “dry spin” the unit sounded quieter than the unit it replaced.

Following the sound measurements and data evaluation of the unit's operation, Fincke was given the go to begin the “wet spin” processing of the unit's first sample. A full run takes about four to five hours.

Mission Specialists Joe Acaba and Ricky Arnold prepared tools and equipment for their spacewalk tomorrow - the third and final planned during Discovery's visit to the station. They also began an overnight “campout” in the Quest airlock to condition their bodies ahead of the spacewalk set to begin at 10:43 Monday morning.

They plan to relocate an equipment cart from one side of the station's Mobile Transporter to the other; attempt to complete a deploy of a cargo carrier that exhibited a balky handle during the second spacewalk Saturday. They also will deploy a payload attach system and complete work to swap electrical relays to the station's gyroscopes. One last task will be to lubricate the latching end effector on the station's robotic arm - a routine maintenance task to prevent stickiness during latching procedures.

Magnus also continued her handover to Japanese astronaut Koichi Wakata, while Flight Engineer Yury Lonchakov attends to maintenance in the Russian section of the International Space Station.

The next status report will be issued Monday morning after wake up, or earlier if events warrant.

News from Commercial Space Watch