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Spacewalk aims to fix solar panel Spacewalk begins to repair panel
(about 8 hours later)
Astronaut Scott Parazynski will attempt a tricky spacewalk on Saturday to try to fix a damaged solar panel on the International Space Station (ISS). A US astronaut has begun a dangerous spacewalk to try to fix a damaged solar panel on the International Space Station (ISS).
The energy-collecting wing developed a rip when it was being unfurled at the port end of the platform on Tuesday.The energy-collecting wing developed a rip when it was being unfurled at the port end of the platform on Tuesday.
Parazynski will ride the end of an extension boom to install home-made "cufflinks" to the broken section. Scott Parazynski is riding the end of an extension boom to install home-made "cufflinks" to the broken section.
If the patch job is a success it will enable the wing to be fully deployed and properly locked in position.If the patch job is a success it will enable the wing to be fully deployed and properly locked in position.
The spacewalk is due to begin at 1028GMT. It will be a testing few hours for Mr Parazynski, who will be supported from a nearby girder by spacewalking colleague Douglas Wheelock.
It will be a testing few hours for Parazynski, who will be supported from a nearby girder by spacewalking colleague Douglas Wheelock. 'Fix it'
Parazynski's suit and tools will have been insulated to ensure he does not get shocked as he tries to fix the damaged panel. The torn solar panel could give a powerful shock if touched.
"We're upward of over 100 volts DC power on that array" commented astronaut David Wolf at the US space agency's Johnson Space Center in Texas. "Go out and fix that thing for us," station commander Peggy Whitson said, as the men left the station more than 200 miles (320 km) above the Earth.
Cufflinks: Engineers have developed a repair solution"It's not the kind of thing that would burn you, but we could get conduction through the heart, let's say, or mild shocks. This is not going to happen. We have very good techniques to insulate and control the array." The outcome of the repairs is of vital importance to future shuttle flights.
Nasa officials say the 35m (115ft) wing probably snagged on a guidewire or guidewire support as it was being unfurled, but until Parazynski gets a close look at the damaged area he will not know precisely what needs to be done to fix it. If the wing is not extended fully, it may not be able to withstand the loading put on the platform when the orbiter docks.
He will go with a collection of tools that can be put to different uses. Mr Parazynski's suit and tools have been insulated to ensure he does not get shocked as he tries to fix the damaged panel.
The panel must be lashed together where it has come apart
Nasa officials say the 35m (115ft) wing probably snagged on a guidewire, or guidewire, support as it was being unfurled, but until Mr Parazynski gets a close look at the damaged area he will not know precisely what needs to be done to fix it.
He is carrying a collection of tools that can be put to different uses.
The cufflinks will be inserted to support the hinges in the retractable panel.The cufflinks will be inserted to support the hinges in the retractable panel.
"They'll also be looking at the snags and the guidewires to see if there is any fraying and then they'll probably cut pieces off that need to be removed so that the [panel] can be folded back properly," said ISS flight director Heather Rarick.
Columbus is Europe's main contribution to the space station projectThe outcome of the repairs is of acute importance to future shuttle flights. If the wing is not extended fully, it may not be able to withstand the loading put on the platform when a 2,000-tonne orbiter docks.
The next shuttle, due in December, is supposed to deliver Europe's main contribution to the ISS project - its Columbus laboratory.The next shuttle, due in December, is supposed to deliver Europe's main contribution to the ISS project - its Columbus laboratory.
Failure to sort the solar panel problem on Saturday would leave Nasa no choice but to delay the December flight while it worked through possible, alternative solutions. That would keep the already much-delayed Columbus sitting on the ground even longer.Failure to sort the solar panel problem on Saturday would leave Nasa no choice but to delay the December flight while it worked through possible, alternative solutions. That would keep the already much-delayed Columbus sitting on the ground even longer.
The ISS is currently being visited by space shuttle Discovery. Astronauts from the orbiter have already attached the new Harmony module to a temporary location on the station. The unit will be moved into a permanent site once the orbiter has left.The ISS is currently being visited by space shuttle Discovery. Astronauts from the orbiter have already attached the new Harmony module to a temporary location on the station. The unit will be moved into a permanent site once the orbiter has left.
Harmony will act as a passageway between three science laboratories: The existing US Destiny lab, and the soon-to-launch European Columbus and Japanese Kibo experimental units.Harmony will act as a passageway between three science laboratories: The existing US Destiny lab, and the soon-to-launch European Columbus and Japanese Kibo experimental units.