Lopez-Alegria, who will make his sixth spacewalk, and Tyurin, with three previous spacewalks to his credit, climbed into Russian Orlan spacesuits Friday to test all systems and communications gear. This ended a week during which the spacewalkers also installed U.S. lights on their suit helmets, reviewed procedures for the extravehicular activity and performed leak checks on the Progress 22 craft currently docked to the Pirs airlock.
The six-hour spacewalk includes a commercial golf demonstration by Tyurin. Under a commercial agreement between the Russian Federal Space Agency and a Canadian golf company, Tyurin will hit a golf ball into space from a spring-mounted tee on the ladder next to the hatch of Pirs. The ball will be tapped over the back of the station's Russian segment so that the ball travels away from the complex. NASA flight controllers have calculated that it will burn up in the atmosphere in about three days. The ball weighs much less than the standard 45 gram golf ball. The ball used for this demonstration weighs three grams, approximately the weight of three paper clips.
During the spacewalk, Tyurin will examine part of the ISS Progress 23 cargo ship. One of the antennas for the Progress' automated docking system may have failed to fold back when the spacecraft approached the aft port of the Zvezda Service Module on Oct. 26. If it's necessary, Tyurin will manually retract that antenna.
Also, Lopez-Alegria and Tyurin will reposition a communications antenna on the aft end of Zvezda associated with next year's docking of the European Automated Transfer Vehicle, check restraining bolts on one of two Russian cargo cranes attached to Pirs and deploy an experiment to measure solar flares.
Wednesday marked the first live high-definition television broadcast from space. It featured Lopez-Alegria, with Reiter serving as camera operator. The broadcasts were conducted by NHK Television in Japan and the Discovery HD Theater. Known as the Space Video Gateway, the HD system onboard transmits high bandwidth digital television signals to the ground through a computer. Previously, high-definition video was recorded and then returned to Earth for viewing.
Flight controllers this week continued to test one of the station's four control moment gyroscopes (CMGs). CMG-3 exhibited high vibrations and electrical currents in the past and was shut down Oct. 9. The recent test results will be compared to a previous series of tests to provide additional data on the state of the gyroscope's accelerometer, lubricant and lubrication of the spin bearings.
CMG-3 is scheduled to be removed and replaced on the STS-118 shuttle mission, targeted for launch in June 2007. The gyroscope will be stowed and returned to Earth on the STS-122 mission next fall. The station continues to function on three healthy CMGs without affecting operations.
Reiter also continued work this week on a suite of European Space Agency science experiments, including one called CASPER. Its objective is to develop ways to help astronauts sleep better during long-duration missions. Alteino Long Term Monitoring of Cosmic Rays or ALTCRISS is another experiment Reiter performed. It is allowing scientists to study the effects of shielding on cosmic rays. The information gained may help engineers better understand the radiation environment and how to provide efficient shielding against it.