2006 Report #5 11:30 pm CST, Friday, February 3, 2006
Space station crew members released a spacesuit-turned-satellite
during the second spacewalk of their mission last night. Called SuitSat, it faintly
transmitted recorded voices of schoolchildren to amateur radio
operators worldwide for a brief period before it ceased sending
signals.
Expedition 12 Commander Bill McArthur and Flight Engineer Valery
Tokarev ventured outside for a five-hour, 43-minute spacewalk to
release SuitSat, conduct preventative maintenance to a
cable-cutting device, retrieve experiments and photograph the
station's exterior. Clad in Russian Orlan spacesuits, McArthur and
Tokarev opened the hatch to begin the spacewalk at 5:44 p.m. EST.
It was the fourth career spacewalk for McArthur and the second for
Tokarev.
After setting up tools and equipment, they positioned the
unneeded Orlan spacesuit on a ladder by the station's Pirs airlock
hatch. The suit reached the end of its operational life for
spacewalks in August 2004. It was outfitted by the crew with three
batteries, internal sensors and a radio transmitter for this
experiment.
The SuitSat (above) provided recorded greetings in six languages
to ham radio operators for about two orbits of the Earth before it
stopped transmitting, perhaps due to its batteries failing in the
cold environment of space, according to amateur radio coordinators
affiliated with the station program. The suit will enter the
atmosphere and burn up in a few weeks. Tokarev pushed the suit away
toward the aft end of the station as the complex flew 225 miles
above the south central Pacific Ocean. The suit initially drifted
away at a rate of about a half meter per second, slowly floating
out of view below the Zvezda Service Module and its attached
Progress cargo craft. The suit is now separating from the station
at a rate of about six kilometers every 90 minutes.
McArthur and Tokarev then moved from Pirs to the Zarya module
where they removed a hubcap-shaped grapple fixture adapter for the
Strela crane. They moved the adapter to Pressurized Mating
Adapter-3 on the Unity module. The Strela fixture was moved to
prepare Zarya for the future temporary stowage of debris
shields.
McArthur and Tokarev made their way to the center truss segment
of the station, where they tried and failed to securely install a
safety bolt in a contingency cutting device for one of two cables
that provide power, data and video to the Mobile Transporter rail
car. The transporter moves along the truss to correctly position
the Canadarm2 robotic arm for assembly work. The Trailing Umbilical
System cable on the nadir, or Earth-facing side of the transporter
was inadvertently severed by its cutter on Dec. 16.
After several attempts to drive the bolt with a high-tech
screwdriver, McArthur wire-tied the cable to a handrail instead.
That left the cable out of its cutting mechanism, disabling the
Transporter from further movement on the station's rail system for
the time being. The Transporter is not needed for assembly work
until the STS-115 mission to install additional truss segments.
The severed cable reel mechanism will be replaced during one of
the three spacewalks by Discovery crewmembers Piers Sellers and
Mike Fossum during the STS-121 shuttle mission later this year.
McArthur and Tokarev moved back to Pirs. Once at the Russian
airlock, they retrieved an experiment to study the effect of the
space environment on microorganisms.
As their final spacewalk task, the crew photographed the
exterior of Zvezda, including Russian sensors that measure
micrometeoroid impacts, handrails, propulsion systems and a ham
radio antenna. McArthur and Tokarev then returned to the Pirs
airlock and closed the hatch at 11:27 p.m. EST. It was the 64th
spacewalk in support of station assembly and maintenance, the 36th
staged from the station, and the 17th conducted from Pirs. In all,
station spacewalkers have accumulated 384 hours and 23 minutes
outside the facility since December 1998.
Meanwhile in Russia,
final preparations were made this week to ship the next Soyuz
spacecraft from Moscow to the Baikonur Cosmodrome launch site in
Kazakhstan. The spacecraft is scheduled to depart Monday and will
launch the 13th station crew in late March.
During the week, the station was maneuvered through a new
procedure using guidance and navigation computers in the Destiny
laboratory to request firings of the thrusters on the Zvezda module
while maintaining overall attitude control through the Control
Moment Gyroscopes.That saves time in handing orientation control of
the station between the U.S. and Russian systems.