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Astronauts prepare for final walk Astronauts make final spacewalk
(1 day later)
The crew of the space shuttle Discovery are preparing for a fourth spacewalk, to fix a jammed solar panel at the International Space Station (ISS). The crew of the space shuttle Discovery have embarked on a fourth spacewalk, to fix a jammed solar panel at the International Space Station (ISS).
Nasa approved the spacewalk when astronauts Robert Curbeam and Sunita Williams struggled to fix the panel after rewiring electrical systems.Nasa approved the spacewalk when astronauts Robert Curbeam and Sunita Williams struggled to fix the panel after rewiring electrical systems.
The spacewalk is scheduled for Monday, and will delay the shuttle's return to Earth by a day. The unscheduled spacewalk means that the shuttle's return to Earth will be delayed by a day.
Nasa said the ISS rewired system was now powered up and operating normally.Nasa said the ISS rewired system was now powered up and operating normally.
The rewiring was delayed after the 2003 Columbia disaster and will provide a power upgrade to support extra equipment.The rewiring was delayed after the 2003 Columbia disaster and will provide a power upgrade to support extra equipment.
Mr Curbeam is an experienced spacewalker who has taken part in all three spacewalks on Discovery's mission to the ISS, and will lead the effort to unjam the solar panel. Mr Curbeam, an experienced spacewalker who has taken part in all three spacewalks on Discovery's mission to the ISS, is leading the effort to unjam the solar panel.
A fourth spacewalk would be a record for an astronaut on a single shuttle mission. A fourth spacewalk is a record for an astronaut on a single shuttle mission.
"Really, if anyone can do it, it's Beamer [Curbeam]. He is rock solid," said Nasa's spacewalk officer Tricia Mack."Really, if anyone can do it, it's Beamer [Curbeam]. He is rock solid," said Nasa's spacewalk officer Tricia Mack.
In an interview on Sunday, Mr Curbeam said: "Probably the most important thing is for us to keep in mind is that since it's my fourth - and you tend to get more and more comfortable as you go along - just to make sure we don't make any mistakes."
The astronauts ventured outside in their spacesuits shortly before 1410 EST (1910 GMT) on Monday.
Panel stuckPanel stuck
The crew were woken up by the Beach Boys track Good Vibrations: "Good morning, Discovery," mission control astronaut Shannon Lucid radioed up.
"We sort of thought that the wake-up music this morning summed up our hopes for the day."
In Saturday's spacewalk, Mr Curbeam left the ISS ahead of Sunita Williams, who was beginning her first mission.In Saturday's spacewalk, Mr Curbeam left the ISS ahead of Sunita Williams, who was beginning her first mission.
"Bye-bye Bob," she said as he exited the station."Bye-bye Bob," she said as he exited the station.
"Welcome to the club, Suni," he replied when she emerged a few minutes later."Welcome to the club, Suni," he replied when she emerged a few minutes later.
A solar panel on the space station failed to retract"It's great to have some good on-orbit electricians working for us," said Stephen Robinson from Nasa Mission Control in Houston, Texas, after the spacewalk was completed. A solar panel on the space station failed to retractAfter several attempts at fixing the jammed solar panel on the ISS, Nasa decided to halt the spacewalk as the astronauts' spacesuits were running short of supplies.
During the spacewalk the astronauts relocated debris shield panels, attached a grapple fixture and performed a test on the partially retracted solar array.
After several attempts at fixing the jammed solar panel on the ISS, Nasa decided to halt the spacewalk as the astronauts' spacesuits were running short of supplies.
The array, which needs to be folded away to make room for new panels, jammed as the astronauts attempted to retract it by remote control.The array, which needs to be folded away to make room for new panels, jammed as the astronauts attempted to retract it by remote control.
It has been six years since the 35m (115ft) wing, which has served as the space station's primary power source, was deployed and it has not been retracted during that period. It has been six years since the 35m (115ft) panel, which has served as the space station's primary power source, was deployed and it has not been retracted during that period.
New solar panels, fitted in September, will take over the job of powering the ISS, boosting its power by about 50%.New solar panels, fitted in September, will take over the job of powering the ISS, boosting its power by about 50%.
Night flightNight flight
The mission is taking place to finish the $100bn (£50bn) station. At least 14 more missions are needed.The mission is taking place to finish the $100bn (£50bn) station. At least 14 more missions are needed.
Discovery blasted off from Florida last weekend in the first night launch of a space shuttle in four years, after being delayed for two days because of bad weather.Discovery blasted off from Florida last weekend in the first night launch of a space shuttle in four years, after being delayed for two days because of bad weather.
Discovery's launch left a fiery trail in the Florida skyThe landing date is now expected to be 22 December back at the Kennedy Space Center.Discovery's launch left a fiery trail in the Florida skyThe landing date is now expected to be 22 December back at the Kennedy Space Center.
Discovery's crew consists of Commander Mark Polansky, pilot William Oefelein and mission specialists Mr Curbeam, Joan Higginbotham, Nicholas Patrick, Ms Williams and the European Space Agency astronaut Christer Fuglesang.Discovery's crew consists of Commander Mark Polansky, pilot William Oefelein and mission specialists Mr Curbeam, Joan Higginbotham, Nicholas Patrick, Ms Williams and the European Space Agency astronaut Christer Fuglesang.
A British-born astronaut, Nicholas Patrick, is among Discovery's crew. For five of the seven astronauts, this is their first shuttle flight.A British-born astronaut, Nicholas Patrick, is among Discovery's crew. For five of the seven astronauts, this is their first shuttle flight.
Ms Williams will stay on at the ISS when Discovery heads home, taking German Thomas Reiter back to Earth.Ms Williams will stay on at the ISS when Discovery heads home, taking German Thomas Reiter back to Earth.