HOUSTON -- Two spacewalking astronauts will staple a space blanket and help fold a stubborn solar array Friday to repair part of the Atlantis orbiter and prime a space station power truss for relocation.
Atlantis astronauts Jim Reilly II and Danny Olivas are due to step outside the International Space Station (ISS) at 1:38 p.m. EDT (1738 GMT) today on a spacewalk primarily aimed at securing a torn heat shield blanket on the space shuttle Atlantis and forcing an old solar array into its storage boxes at the pinnacle of the orbital laboratory.
“We are set to go tomorrow,” Reilly told Mission Control late Thursday.
Reilly and Olivas are slated to spend more than six hours working outside the ISS on what will be the third spacewalk of NASA’s STS-117 shuttle mission aboard Atlantis. Commanded by veteran spaceflyer Rick Sturckow, the shuttle’s seven-astronaut crew has delivered a new crewmember, starboard trusses and two expansive new solar arrays to the ISS during their planned 13-day mission.
Aboard the space station, the three-astronaut crew of Expedition 15 will spend much of the early part of Friday working with Russian flight controllers in work aimed at recovering a critical set of computers responsible for Russian segment ISS systems.
Shuttle blanket surgery
First up for Olivas will be the shuttle blanket repair, an ad hoc heat shield fix requiring the use of medical staplers, a dental tool and wire pins.
The 4-inch by 6-inch (10-centimeter by 15-centimeter) triangular flap of a protective blanket on Atlantis’ left Orbital Maneuvering System (OMS) tore loose during Atlantis’ June 8 launch.
While not a risk to the shuttle crew, the tear did expose a section of the OMS pod’s internal structure prompting concerns that it could be damaged during reentry and require a lengthy repair back on Earth that could be avoided.
From a perch at the tip of Atlantis’ robotic arm, Olivas is expected to pat down the uplifted blanket, secure it to an adjacent blanket with two rows of medical staples, and then anchor it into nearby heat-resistant tiles by using the dental tool to poke holes for the pins.
“We feel that’ll be a great repair and bring Atlantis home safely,” STS-117 mission specialist Patrick Forrester told the television station KUSA TV Thursday on NASA TV.
While Olivas repairs the blanket, Reilly will install a vent valve for a U.S. oxygen generator to NASA’s Destiny laboratory at the ISS.
More solar array retraction
The bulk of today’s spacewalk is reserved for the space station’s starboard-reaching solar wing extending from the top of the outpost’s mast-like Port 6 (P6) truss.
For the third day in a row, astronauts will work in concert to try and retract the recalcitrant array.
Atlantis astronauts Patrick Forrester and Steven Swanson poked and prodded snagged areas on the 115-foot (35-meter) array to clear it for retraction during a Wednesday spacewalk, but fell short of a full furling. Attempts to reel in the array via remote also made some progress, though jammed grommets held it fast at about halfway retracted.
Like Forrester and Swanson, Reilly and Olivas will carry orange tape-wrapped tools - including an L-shaped piece dubbed the “hockey stick” - to nudge the array’s individual pleats to ensure they fold away properly.
Because the P6 array, known as P6-2B, initially crossed over the new starboard solar arrays, it had to be retracted clear of them so those new solar wings could rotate and track the Sun. Atlantis crew reached that benchmark on Wednesday, but now must furl the array completely so the P6 truss can be relocated to its final position at the end of the station’s portside in a later shuttle flight.
“The whole team comes together for our third spacewalk,” Sturckow said Thursday. “We’re expecting big things tomorrow.”
NASA is broadcasting the space shuttle Atlantis' STS-117 mission live on NASA TV. Click here for mission updates and SPACE.com's video feed.
- SPACE.com Video Interplayer: Space Station Power Up with STS-117
- STS-117 Power Play: Atlantis Shuttle Crew to Deliver ISS Solar Wings
- Complete Shuttle Mission Coverage