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Crew may do extra ISS spacewalk Second ISS spacewalk completed
(about 8 hours later)
The Discovery crew may have to perform an unscheduled spacewalk to fix a stuck solar panel on the International Space Station (ISS). The Discovery crew has successfully completed a second spacewalk to rewire the International Space Station (ISS).
Astronauts Robert Curbeam and Christer Fuglesang began the five-hour excursion at 1441 EST (1941 GMT) on Thursday.
To prepare for the work, flight controllers on the ground powered down half of the station's systems.
A third spacewalk is planned for Saturday, but astronauts may also perform a fourth, unscheduled outing to fix a stuck solar panel on the ISS.
The array, which needs to be folded away to make room for new solar 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 solar panels, jammed as the astronauts attempted to retract it by remote control.
Nasa officials are considering the possibility of an extra spacewalk to carry out a hands-on repair. 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since the 35m (115ft) wing, which has served as the space station's primary power source, was deployed and it has not been retracted during that period.
A second spacewalk to rewire the ISS has been completed, Nasa says. New solar panels, fitted in September, will take over the job of powering the ISS, boosting its power by about 50%.
Mission specialists Robert Curbeam and Christer Fuglesang, who performed the first spacewalk of the mission, began work at 1541EST (1941 GMT). The team spent hours grappling with the panel, comparing the process to folding up a road map, before finally admitting defeat after the system stuck.
Before the duo began the spacewalk, flight controllers on the ground powered down half of the station. A solar panel on the space station failed to retract
An extra spacewalk would take the total number during the mission to four.
New panels
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since the 35m (115ft) panel, which has served as the space station's primary power source, was deployed and it has not been retracted during that period.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.
During the first spacewalk, the astronauts spent hours grappling with it, comparing the process to folding up a road map, before finally admitting defeat after the system jammed.
The solar array needs to be folded away to make way for new panels
ISS resident Michael Lopez-Alegria told Houston: "We all tried as much up here as you guys did on the ground and it just wasn't going to work for us today.ISS resident Michael Lopez-Alegria told Houston: "We all tried as much up here as you guys did on the ground and it just wasn't going to work for us today.
"But that stuff happens and I'm sure we'll get through it.""But that stuff happens and I'm sure we'll get through it."
They will begin to rewire the station to enable it to use the power produced by new solar arrays. On Friday, the team will attempt to wiggle the panel free from inside the ISS.
This should boost the ISS's power by about 50%. However if this fails, Nasa officials are considering the possibility of an extra spacewalk to carry out a hands-on repair, which would take place on Sunday or Monday.
In preparation for the spacewalk, the two astronauts are "camping out" in the station's airlock.
The third space walk is scheduled for Saturday, after which the fourth unscheduled walk may take place.
Night flightNight flight
The mission is taking place to finish the $100bn (£50bn) station. At least 14 more missions are needed.
Discovery blasted off from Florida at the weekend in the first night launch of a space shuttle for four years, after being delayed for two days because of bad weather.Discovery blasted off from Florida at the weekend in the first night launch of a space shuttle for four years, after being delayed for two days because of bad weather.
The first spacewalk took place on Tuesday Discovery's launch left a fiery trail in the Florida sky
The landing date is set for 21 December back at the Kennedy Space Center.The landing date is set for 21 December back at the Kennedy Space Center.
It is as yet unclear whether an additional spacewalk would prolong the trip which is scheduled to last 12 days.It is as yet unclear whether an additional spacewalk would prolong the trip which is scheduled to last 12 days.
Discovery's crew consists of Commander Mark Polansky, pilot William Oefelein and mission specialists Robert Curbeam, Joan Higginbotham, Nicholas Patrick, Sunita Williams and the European Space Agency astronaut Christer Fuglesang.Discovery's crew consists of Commander Mark Polansky, pilot William Oefelein and mission specialists Robert Curbeam, Joan Higginbotham, Nicholas Patrick, Sunita 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.
One of crew, US astronaut Sunita Williams, will stay on at the ISS when Discovery heads home, taking German Thomas Reiter back to Earth.One of crew, US astronaut Sunita Williams, will stay on at the ISS when Discovery heads home, taking German Thomas Reiter back to Earth.
At least 14 more missions are needed to finish the $100bn (£50bn) station.