Phillips also conducted work with a viscosity measurement experiment that collects information on the behavior of liquids in microgravity that have different thickness, or viscosity. The experiment may provide insight to researchers designing new hardware for space travel and could have industrial applications on Earth.
Phillips and Krikalev spent part of Tuesday practicing photography techniques with digital cameras in the Zvezda Service Module. The techniques will be used to capture high resolution imagery of the condition of Discovery's heat shield at a distance of 600 feet as the Shuttle approaches for docking on the third day of the STS-114 mission.
The crewmembers will use 400 millimeter and 800 millimeter lenses from two windows in Zvezda to focus on Discovery's thermal protection tiles and the reinforced carbon-carbon shield.
Discovery Commander Eileen Collins will fly Discovery through a backflip as it approaches the Station, allowing Krikalev and Phillips to document all sides of the vehicle. They will shoot as many frames as possible during the minute and a half Shuttle flip. Those images will be transmitted to the ground for analysis.
For the second week, the crew activated solid fuel oxygen generating canisters in Zvezda to replenish the cabin atmosphere. The canisters, one of multiple oxygen supplies that remain available onboard, are being used following the depletion of oxygen reserves in tanks in the Progress cargo vehicle and in the absence of an operating Elektron oxygen-generation system.
The next Progress cargo ship to launch to the Station in mid-June will carry new supplies of oxygen tanks and solid fuel canisters as well as electronic components for the Elektron. Oxygen supplies onboard and those on upcoming cargo vehicles can accommodate the crew into next year.
Earlier today, Krikalev tested the voltage of some of the Elektron's existing components to help Russian specialists in their ongoing troubleshooting efforts. Krikalev confirmed that the electrolyzer unit, part of a system that splits water into hydrogen and oxygen, showed no voltage readings and is presumed to have failed.
Krikalev also worked on a procedure to bypass one of the cables in the Russian segment condensate removal system that has developed a blockage.
The crew is scheduled for a light duty weekend, including routine housekeeping tasks and family conferences.