McArthur and Tokarev left the station unoccupied for about half an hour as they relocated the Soyuz TMA-7. Tokarev unodocked the Soyuz at 2:46 a.m. CST while the station orbited 225 miles above the south Atlantic just east of South America. They redocked to the Earth-facing port of the nearby Zarya module at 3:05 a.m. As they docked, the station was over the Sahara Desert as the recently installed Port 1 Truss television camera provided dramatic views of the operation.
The Soyuz move will allow the Pirs Docking Compartment to be used as an airlock for an upcoming Russian spacewalk. That spacewalk, to be the second of three possible spacewalks during their mission, currently is scheduled for Dec. 7. However, managers are reviewing the schedule and the spacewalk may be delayed to early next year to ease the crew's workload. McArthur and Tokarev must finish unpacking the ISS Progress 19 cargo ship now docked to the complex, prepare it for undocking and get ready for the Dec. 23 arrival of the next Progress supply ship.
Today, Tokarev, in the center seat of the Soyuz, disengaged hooks and latches holding the craft to Pirs and backed it about 80 feet away from the complex. With McArthur seated to his left, Tokarev piloted the Soyuz forward along the station about 45 feet. He then rotated the capsule to align it with Zarya’s docking port. A few minutes after the Soyuz linked up to Zarya, hooks and latches engaged, establishing a firm connection. The crew is scheduled to re-enter the station just before 9 a.m., after a series of leak checks are completed.
The Soyuz will be the crew's ride home at the end of its six-month stay on the orbiting laboratory. It also serves as a lifeboat in the event the crew must evacuate the station.
Earlier this week, McArthur spent several hours photographing samples of colloids that had been undisturbed in the station’s microgravity environment for more than a year. The work is part of an experiment called the Binary Colloidal Alloy Test. The behavior of these supercritical fluids is important because they combine the properties of liquids and gases. A better understanding of their reaction in the weightless environment of space could help in the development of new drugs, cleaner power and interplanetary transportation.
The crew will begin an extended sleep period at about 11:30 a.m. and will awaken about midnight Saturday to begin a weekend of light duty.