The Expedition 10 crew of the International Space Station completed another productive week of their mission last week, focusing on science experiments, Progress undocking preparations and robotic arm operations.
Both crew members are of Asian decent, and commemorated a New Year as they passed their four-month mark in space. Commander and NASA Station Science Officer Leroy Chiao and Flight Engineer Salizhan Sharipov delivered a special message in honor of the Chinese Lunar New Year celebrated last Tuesday. The message included greetings in Russian and Mandarin, which Chiao speaks fluently.
Chiao and Sharipov began the workweek with a checkout of the onboard defibrillator as well as continued preparation and packing of items to be transferred to Space Shuttle Discovery’s Multipurpose Logistics Module during the Shuttle Return to Flight mission, designated STS-114, scheduled for May or June. The preparations included several hours early in the week with stowage and audit activities of spacesuit equipment in the Quest Airlock, including inventory of tool and maintenance kits.
Other technical tasks completed last week included installation of a Navigation Receiving Module in the Russian segment for Station attitude determination. Chiao continued work in the Quest, regenerating two Metal Oxide or METOX canisters for use in U.S. spacesuits. Those canisters “scrub” air exhaled into the spacesuit system of carbon dioxide, and recharge the oxygen.
The crew also deactivated the Russian Elektron oxygen generation system last Wednesday. The planned deactivation allows the use of oxygen from the docked Progress cargo spacecraft. It also reduces Progress to the weight necessary for its undocking scheduled for Feb. 27. Two repressurizations are planned. The first repress, of about 10mmHg, is scheduled for Feb. 15, and the second, about 15mmHg, for Feb. 25. The Elektron is scheduled to be reactivated in early March.
After a successful preplanned attitude transition maneuver last Tuesday, return of attitude control was interrupted when one of the Control Moment Gyroscopes (CMG) became saturated, or overwhelmed, and lost its ability to control the Station’s orientation.
Attitude control was automatically taken over by the Russian Attitude Control System thrusters for about one orbit, using about 14 kilograms of propellant. The CMG saturation was the result of an incorrect ground command. The ground team recognized the source of the error and issued the command to properly reposition the CMG. The CMGs then resumed control and the thrusters were turned off. The crew’s workday was unaffected by the events.
Friday night, the Station’s toilet in the Zvezda Service Module stopped working. The crew, with the support of Russian ground controllers, replaced virtually all major toilet components this weekend with spare parts aboard the Station. Most of the original components had been nearing the estimated end of their operational life. The crew also replaced the toilet’s control panel on Sunday. The work has restored the toilet to full normal operations. While the Station toilet system repairs were under way this weekend, the crew used the toilet aboard the docked Soyuz spacecraft.
Along with their technical tasks and maintenance activities, the crew supported almost 14 hours of science and medical experiments. Sharipov worked on the Cardio-Cog experiment and Plasma Crystal, a Russian experiment that studies plasma dust crystals and fluids in microgravity. Chiao captured still photos documenting the progress of the Binary Colloidal Alloy Test, which looks at the long-term behavior of colloid particles suspended in fluids, such as ink, paint and milk.
Both crewmembers participated in continued studies as part of the ADUM, or Advanced Diagnostic Ultrasound in Microgravity, experiment. After some computer-based proficiency training earlier in the week, last Friday, they performed scans with Chiao serving as the test subject. This experiment could have applications on Earth by assisting in the diagnosis of patients in rural or remote areas.
Also highlighting the crew’s week was a live education event with Crossroads Elementary School, a NASA Explorer School in Saint Paul, Minn. Last Tuesday the crew also had a special conference call with Anatoly Perminov, Head of the Russian Federal Space Agency (Roscosmos), and Edelhard Bulman, the German Minister of Education and Science, who were discussing future German/Russian space cooperation ventures.
Information about crew activities on the Space Station, future launch dates and Station sighting opportunities from Earth is available on the Internet at:
http://spaceflight.nasa.gov/