Crew Preparing For Spacewalk, Station's Attitude Adjusted
Space Station crewmembers marked their 100th day in space
Friday, ending a workweek focused on preparations for their first
spacewalk, planned for Wednesday, January 26.
Expedition 10 Commander and NASA ISS Science Officer Leroy Chiao
and Flight Engineer Salizhan Sharipov are scheduled to leave the
Pirs Docking Compartment airlock at 0125 CST. Most of their
spacewalk tasks involve outfitting the outside of the Zvezda
Service Module.
They will install a work platform, mount a robotics experiment,
check vents on systems that help control the Station’s
atmosphere and install a scientific experiment.
After completing the work outside Zvezda, they will move back to
Pirs. There, outside the docking compartment, they will
install an experiment that examines the impact of spaceflight on
microorganisms. They are expected to re-enter Pirs and close the
hatch about 0700.
Sharipov and Chiao completed one spacewalk prerequisite Friday
morning. Both did the required cardiovascular evaluation exercise
using one of the Station’s bicycle-like devices. They also
did leak, valve and pressure checks on their Orlan spacesuits and
the Orlan interface units in Pirs, completed suit communications
checks and did a review of the spacewalk plan with flight
controllers in Moscow.
Spacewalk activity earlier in the week included spacesuit
battery charging beginning Tuesday, as well as preparation of
spacewalk hardware and tools that day. They spent three hours
staging equipment and tools on Wednesday, and on Thursday they
activated and tested the suits.
Both suits will have red stripes. Chiao will be distinguishable
by the United States flag on his shoulder.
The spacewalk will be broadcast live on NASA Television,
beginning at 0000 CST on January 26. Coverage will continue through
the end of the spacewalk.
In other activities during the past week, flight controllers on
January 15 raised the Station’s altitude by about 5.5 statute
miles in a 20-minute reboost using engines of the ISS Progress 16
cargo craft docked at the rear of Zvezda. That was done to put the
Station in the proper orbit for the arrival of ISS Progress 17
spacecraft, scheduled for launch February 28 and docking March
2.
For much of the week, flight controllers conducted vibration and
current tests on one of the 600-pound control moment gyros (CMGs)
that control the orientation of the Station in space. The CMGs
normally operate at 6,600 rpms, but can be operated at 15 other
speeds. The test involved running CMG 2 at each of those speeds for
four hours.
The CMGs use solar power. Three of the four on board are
functioning, though the Station’s attitude could be
controlled with two. The CMG which failed in mid-2002 is to be
replaced on the next Shuttle mission.