Mike Fincke, commander of the , and Flight Engineer Yury Lonchakov spent five hours and 38 minutes on their space walk. As part of an investigation into the steeper than normal re-entries into the earth's atmosphere of the of the Expedition 15 and Expedition 16 Soyuz spacecraft, space station engineers will use the electromagnetic energy measuring device, dubbed the Langmuir probe, to calculate the energy's effects on bolts that are suspected to a cause of the problem, according to .

Last March, the crew of the space shuttle Endeavour carried the makings of a with a 30-foot wingspan to the International Space Station. The robot, named Dextre by its makers at the Canadian Space Agency http://www.asc-csa.gc.ca/eng/missions/sts-123/default.asp in Saint-Hubert, Quebec, is designed to take on most of the maintenance jobs required outside of the space station, cutting back on the number of dangerous space walks the astronauts must make.

Although and awaiting an assignment, it was not used in this week's outside work.

Dextre isn't the only recent high-tech addition to the space station.

Earlier this month, an electronic nose onto the facility. The ENose, which has an array of 32 sensors, is designed to sniff out dangerous chemicals like ammonia, mercury, methanol and formaldehyde, that could escape into the air in the space station.