Two residents of the International Space Station ventured outside the complex Wednesday for a 5 hour, 38 minute spacewalk to reposition, deploy and relocate equipment, and to take a swing at a commercially sponsored activity.

With Flight Engineer Thomas Reiter inside to monitor systems, Expedition 14 Commander Mike Lopez-Alegria and Flight Engineer Mikhail Tyurin opened the hatch to the Pirs Docking Compartment airlock at 6:17 p.m. CST as the station flew over the Atlantic Ocean near the west coast of Africa. They wore Russian Orlan spacesuits for the 19th spacewalk conducted out of Pirs since it was mated to the Russian segment of the station in September 2001 during Tyurin's first flight as part of Expedition 3.

The start of the spacewalk was delayed more than an hour after Tyurin encountered a problem with a cooling hose for his spacesuit. He climbed out the suit to reposition the hose, and uninterrupted cooling for the suit was restored.

After setting up tools and equipment outside Pirs, Tyurin placed a three- gram golf ball on a spring-mounted tee and clamped it onto the ladder next to the Pirs hatch. Appearing uncomfortable with his feet planted on the ladder, Tyurin used a gold-plated six-iron to tap the golf ball safely away from the aft end of the Zvezda Service Module. Tyurin said he was pleased with his golf shot, and Russian flight controllers chose not to have him hit another ball so the crew could tackle other tasks.

Tyurin's golf shot was part of a demonstration for a commercially sponsored endeavor between a Canadian golf company and the Russian Federal Space Agency. The golf club and three balls were flown to the station on recent Russian Progress cargo ships. NASA's safety analysis showed that the balls will re-enter the Earth's atmosphere and burn up in about three days. The balls weigh only about as much as three one-dollar bills.

The two spacewalkers then moved to the end of Zvezda where the recently arrived ISS Progress 23 cargo ship is docked. Tyurin released a latch on one of the antennas for the craft's Kurs automated rendezvous system that failed to retract when the Progress docked on Oct. 26. Tyurin and Lopez-Alegria attempted to move the so-called "orientation" antenna back to its retracted and stowed position with their hands and with a prybar, but the antenna would not budge. Russian flight controllers also sent commands to drive the antenna to its retracted position, but that also failed.

The spacewalkers took a number of pictures to send to Russian engineers, who will evaluate options for freeing the stuck antenna on a future spacewalk. The engineers surmise something may be frozen in the linkage for the antenna's drive mechanism, preventing it from moving.

While at the aft of Zvezda, Tyurin and Lopez-Alegria spent a few minutes removing and repositioning one of several communications antennas previously installed around the module's docking port. This will assist the docking of the European Automated Transfer Vehicle that will be launched on an Ariane 5 rocket from Kourou, French Guiana next year.

In its previous location, the antenna partially blocked the opening of one of Zvezda's engine covers. The antenna was reinstalled less than a foot from its original position, out of the way of future operations with the engine.

Next, Lopez-Alegria and Tyurin moved to the top of the forward section of Zvezda to install an experiment called "BTN-Neutron" that will measure the volume of neutron particles emitted by solar flares that reach low Earth orbit. The crew wrapped up its work by jettisoning a pair of thermal covers for the experiment that will be tracked by flight controllers to ensure they pose no possibility of hitting the station or the shuttle Discovery that is scheduled for an assembly mission to the station in a few weeks.

It was the 73rd spacewalk in support of station assembly and maintenance totaling 444 hours and 14 minutes of time outside the outpost and the first of four scheduled during Expedition 14. The spacewalk was the sixth in Lopez- Alegria's career and the fourth for Tyurin.

FMI: www.nasa.gov/station