June 2, 2006

Joe Pally
Headquarters, Washington

James Hartsfield
Johnson Space Center, Houston



The residents of the International Space Station ventured outside
their orbital home Thursday night to conduct a 6-hour, 31-minute
spacewalk to repair, retrieve and replace hardware on the U.S. and
Russian segments of the complex.

Clad in Russian Orlan spacesuits, Expedition 13 Commander Pavel
Vinogradov and NASA Flight Engineer and Science Officer Jeff Williams
opened the hatch to the Pirs Docking Compartment airlock at 6:48 p.m.
EDT to begin the 65th spacewalk devoted to station assembly and
maintenance. It was the sixth spacewalk for Vinogradov and the second
for Williams. The spacewalk began as the station flew 220 miles over
southern Asia.

After setting up tools and tethers outside Pirs, Vinogradov and
Williams used the telescoping boom, designated Strela, attached to
the airlock to transport them to the forward area of the Zvezda
Service Module that connects to the Zarya Module. There, Vinogradov
installed a new nozzle to a valve that helps vent hydrogen into space
from the Elektron oxygen-generator in Zvezda. Elektron uses the
process of electrolysis to separate hydrogen and oxygen from water in
the system. Oxygen is circulated into the cabin atmosphere while
hydrogen is vented overboard. An existing nozzle on the hull of
Zvezda used for that purpose had become clogged, reducing Elektron’s
efficiency, forcing Elektron to use the same vent line currently
employed by a contamination monitoring device.

Two weeks ago, Vinogradov rigged a vent line inside Zvezda as the
precursor to the installation of the new vent valve nozzle on the
exterior of the module. The refurbished Elektron is scheduled to be
reactivated on Monday.

Next, the two moved to the aft end of Zvezda where they took pictures
of one of several antennas designed to provide navigational
information for the unpiloted docking of the European Automated
Transfer Vehicle (ATV), scheduled to make its maiden flight next
year. Russian engineers suspect the antenna’s cable may have
prevented a cover on one of Zvezda’s reboost engines from opening
during an aborted test firing earlier this year.

Later, Vinogradov took up cable slack from another ATV navigation
antenna and took pictures for technicians to study.

While on the Russian segment of the station Vinogradov removed a
device called Kromka from Zvezda’s hull has collected jet thruster
residue while Williams retrieved the third in a series of three
canisters from the outside of Pirs in an experiment called Biorisk
that studied the effect of the space environment on microorganisms.
Both Kromka and Biorisk were brought inside and will be returned to

Williams also collected a contamination monitoring unit from Pirs and
returned it to the cabin for later analysis.

With the crew slightly behind schedule, a decision was made to extend
the maximum time for the spacewalk. Following that decision, control
of the spacewalk was handed from the Russian flight control team at
the Russian Mission Control Center outside Moscow to the U.S. flight
control team at Mission Control, Houston, as planned.

Vinogradov and Williams maneuvered themselves on the Strela to the
juncture of the Russian and U.S. segments of the outpost, and then
moved to the station’s truss. They removed a video camera on the
Mobile Base System that sits upon a rail car that moves up and down
the truss to position the station’s robotic arm for assembly work.
They replaced the camera that failed in February 2005 with a new one.

Russian flight controllers reassumed responsibility for the spacewalk
as Vinogradov and Williams used Strela to move back to the Pirs
Docking Compartment. They re-entered the station and closed the hatch
at 1:19 a.m. EDT to conclude their excursion.

The crew will reactivate station systems early this morning and open
up the internal hatches between the U.S. and Russian segments before
beginning a sleep period that will extend into Friday afternoon.
Vinogradov and Williams will enjoy a few days of relaxation through
early next week.

The next station status report will be issued Friday, June 9. For more
about the crew’s activities and station sighting opportunities,