The Station is now orbiting at an altitude of 222 statute miles, nearly two miles higher than at the start of the week, following a Russian ground-commanded reboost of the complex Wednesday using the engines of the Russian Progress resupply ship docked to the Zvezda Service Module. While the engine firing to raise the Station's altitude lasted the planned duration of 9 minutes and 9 seconds, the use of fuel from one of the Progress' two fuel tanks rather than the fuel tank on Zvezda resulted in a slightly lower performance of the engines, leaving the Station slightly below its expected final altitude from the reboost.
While the lower altitude does not impact operation of the Station, a team of Russian system experts has been set up to investigate the cause and determine if any action will be required to compensate for the lower altitude. Options under consideration include a second reboost early in December or a possible one-day change in the launch of the next resupply ship, ISS Progress 16, scheduled to lift off Dec. 23 from the Baikonur Cosmodrome in Kazakhstan.
Also during the week, Expedition Commander and NASA Science Officer Leroy Chiao and Flight Engineer Salizhan Sharipov conducted science experiments, checked Russian Orlan spacesuits and performed routine Station housekeeping activities.
On Monday, the crew completed ultrasound scans as part of the Advanced Diagnostic Ultrasound in Microgravity experiment (ADUM). This experiment, first performed during Expedition 5, is designed to determine the ability of astronauts in space to conduct exams using this onboard medical device. If successful, the experiment may have widespread applications in emergency and rural health care on Earth.
A second experiment was conducted this week in the Destiny Laboratory. Known as the Serial Network Flow Monitor (SNFM), the experiment uses crew-installed software to monitor communications and analyze the amount of data flowing between payloads. In other science work, Sharipov collected samples for the PLANT experiment and participated in two Russian programs: a medical operations test dubbed HEMATOKRIT that measures red blood cell count and SPRUT, a study of human body fluids.
Throughout the week, Sharipov also worked on two Russian Orlan spacesuits. He removed parts from one suit that has exceeded its lifetime on orbit and will be discarded next month when the ISS Progress 15 cargo ship is undocked for disposal. He also tested a new Orlan suit that he will wear during a pair of spacewalks with Chiao in January and March.
On Tuesday, the crew talked with students at a middle school in Gaithersburg, Md. The event was held with the Department of Education to highlight the benefits of international relationships and cooperation during the fifth annual International Education Week.
Both crewmembers conducted routine Station maintenance activities including a cleaning of an atmosphere scrubbing system electronics box and the experiment rack areas of the Destiny Lab. Chiao also installed fireport labels and both took part in crew medical officer skills training. Chiao spent time Friday taking inventory of U.S. items that also will be disposed in the Progress resupply ship next month.
The crew wrapped up the week with a ham radio pass with students in Mare, Italy. Over the weekend, the crew will enjoy some off-duty time, private family conferences and a few small tasks such as battery charging and routine housekeeping.
Next Wednesday, the thrusters on the ISS Soyuz 9 return craft mated to the Pirs Docking Compartment will be test-fired in advance of the planned undocking of the vehicle by the crew on Nov. 29 for its redocking to the Zarya module. The brief relocation flight will free up Pirs for sole use as an airlock for the two spacewalks early next year.