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Spacewalk, Harmony installation on tap BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: October 26, 2007 Astronauts Scott Parazynski and Doug Wheelock are gearing up for a six-and-a-half hour spacewalk today to help install the new Harmony module on the international space station. They also plan to retrieve an S-band antenna assembly for return to Earth and prepare a solar array truss segment for relocation later in the mission. The astronauts spent the night in the space station's Quest airlock module at a reduced pressure of 10.2 pounds per square inch to help purge their bloodstreams of nitrogen in preparation for work in NASA's low-pressure spacesuits. The excursion was scheduled to begin around 6:30 a.m., but the crew was running a half hour ahead of schedule earlier today and the spacewalk could begin early. This will be the 93rd spacewalk devoted to station assembly and maintenance since construction began in 1998, the 16th so far this year and the first of five planned for Discovery's mission. Going into today's EVA, 72 astronauts and cosmonauts from the United States, Russia, Canada, Japan, Germany, France and Sweden had logged 567 hours 59 minutes of spacewalk time building the international lab complex. For identification, Parazynski (call sign EV-1) will be wearing a spacesuit with red stripes around the legs. He is a veteran of three previous spacewalks. Wheelock (EV-2), making his first EVA, will be in an all-white suit. The space station's robot arm, or SSRMS, will be used to move the Harmony module from Discovery's cargo bay to a temporary attachment point on the left side of the central Unity module. The SSRMS will be operated by Discovery flight engineer Stephanie Wilson and newly arrived space station flight engineer Dan Tani. "Doug Wheelock and I will go out the hatch together," Parazynski said in a NASA interview. "It will be Doug's first spacewalk. I'm looking forward to seeing him have that experience. Our first activity right off the bat will be to transfer an S-band antenna that will be returned to the ground for servicing and then flown back up, on a future flight as a spare. The reason we have to do it so early in the flight - it's not our highest priority activity - it's just that's the only time the robotic arm is available and in position to support this activity. So we'll pluck this off of the Z1 truss through a handoff, we call it a leap frog maneuver. Doug will hand the SASA antenna to me; it's about 10 feet, 8 to 10 feet in length. I'll hold on to it, then he'll jump into the space station robotic arm, I'll hand it back to him, then he'll take a beautiful ride down to the payload bay, while I translate hand over hand, to support him in installing that on the side wall of the orbiter for return to Earth. "Then we really get into the meat of our assembly activities. We'll activate the Node 2 or Harmony module in the payload bay," Parazynski said. "First we'll be translating a payload and grapple fixture that's on a side wall in the payload bay, and we'll temporarily stow it on the front end of the node. And I'll get a free ride to its installation location. So we'll just tether it in place up on the front of the node and then we'll go to the back of the payload bay and we'll move some protective covers on the seals that we'll mate to the Unity module. We'll also work with some power connectors, the launch activation cable on the front of the module and some other cables on the back of the node." Harmony, providing an additional 1,230 cubic feet of habitable volume, will be temporarily attached to the left side of the station's central Unity module, which connects the U.S. and Russian segments of the complex. After Discovery departs, Whitson, Tani and Expedition 16 flight engineer Yuri Malenchenko will use the station's robot arm to detach the lab's main shuttle docking port so it can be bolted onto Harmony. Then Harmony will be detached and permanently mounted on the front end of the U.S. Destiny laboratory module. European and Japanese research modules will be attached to Harmony's left and right ports in December and early next year. While Wilson and Tani begin pulling Harmony from the cargo bay with the station's robot arm, Parazynski and Wheelock will float up to the central Z1 truss and begin work to prepare the P6 solar array truss for relocation later in the mission. "While we're outside, preparing the P6 for its move, inside Stephanie and Dan will be working, very, very hard with the robotic arm," Wheelock said. "(Pilot) George Zamka will be operating our common berthing mechanism, the actual physical mechanism that connects the two modules together. So they're very busy inside and out, during EVA 1." Designed as the sixth and final segment of the port, or left, side of the station's main power truss, P6 was mounted at the center of the station in December 2000 to provide power to the U.S. segment during the initial stages of assembly. Now, with identical solar panels in place on the left and right sides of the main power truss, NASA needs to move P6 to its permanent position on the far left end of the beam. The 35,000-pound segment's huge arrays, stretching 240 feet from tip to tip, were stowed during shuttle missions last December and June. "Once we're completed with all our work in the payload bay, we'll translate back up to the airlock and drop off some gear, and then we'll head up to the P6 truss," Parazynski said. "Again, these are all independent, closely choreographed, tasks. I'll begin demating the (ammonia) cooling umbilicals that have been connected between P6 and the Z1 truss for almost seven years now. So I'll have to close those valves very carefully and stow them back on the Z1 truss. We're hoping for no leaks, but since the valves have been operational for so long, that's one area of concern that we don't want to get any contamination. "While I'm doing that, Doug will be up on the P6 truss about 10 or 15 feet higher than me, and he'll be deploying a blanket over the radiator there. I will join him for the final activities associated with that radiator blanket. And then we'll go to the top of the world, the top of the P6 truss, and we'll be installing two protective thermal blankets on sequential shunt units. They're basically large power boxes, associated with each of the large P6 solar arrays. So we'll put those blankets on, probably take a few pictures, I imagine, because that vantage point up there is just spectacular. And that will be the completion of our first spacewalk." Here is a timeline of today's activity (in EDT and mission elapsed time; includes revision B of the NASA TV schedule): EDT........DD...HH...MM...EVENT 01:38 AM...02...14...00...STS/ISS crew wakeup 02:13 AM...02...14...35...EVA-1: 14.7 psi repress/hygiene break 03:23 AM...02...15...45...EVA-1: Campout EVA preps 04:43 AM...02...17...05...ISS: Tani pressure suit leak checks and drying 04:53 AM...02...17...15...EVA-1: Spacesuit purge 05:08 AM...02...17...30...EVA-1: Spacesuit prebreathe 05:58 AM...02...18...20...EVA-1: Crew lock depressurization 06:33 AM...02...18...55...EVA-1: Airlock egress 06:53 AM...02...19...15...EVA-1: S-band antenna retrieval 07:33 AM...02...19...55...EVA-2: EV2-: S-band antenna stow 07:43 AM...02...20...05...EVA-1: EV-1: Node prepped for unberthing 08:08 AM...02...20...30...EVA-1: EV-1: S-band antenna stow 08:43 AM...02...21...05...EVA-1: EV-1: Node prepped for unberthing 08:48 AM...02...21...10...EVA-1: EV-2: Node prepped for unberthing 10:23 AM...02...22...45...Station arm (SSRMS) grapples Harmony (node 2) 10:23 AM...02...22...45...EVA-1: EV-1: Disconnect Z1/P6 fluid lines 10:43 AM...02...23...05...SSRMS unberths Harmony 10:53 AM...02...23...15...EVA-1: EV-2: P6 aft radiator shroud 11:38 AM...03...00...00...EVA-1: EV-1: P6 shroud 11:53 AM...03...00...15...EVA-1: Sequential shunt unit shroud 12:28 PM...03...00...50...EVA-1: Airlock ingress 12:33 PM...03...00...55...Harmony attached to Unity leftside port 01:08 PM...03...01...30...EVA-1: Airlock repressurization 01:18 PM...03...01...40...Spacesuit servicing 01:28 PM...03...01...50...SSRMS ungrapples Harmony 02:23 PM...03...02...45...Harmony/Unity leak checks 03:00 PM...03...03...22...Mission status briefing on NASA TV 05:00 PM...03...05...22...Post-MMT briefing on NASA TV 05:38 PM...03...06...00...STS/ISS crew sleep begins 06:00 PM...03...06...22...Daily video highlights reel on NASA TV 10:30 PM...03...10...52...Flight director update on NASA TV "EVA is the ultimate astronaut experience, I think," Parazynski said. "But to be perfectly honest, celebrating a job well done, mission success, I think one of our perpetual fears is not doing the job well, to not get the job done. So I'm very focused when I'm outside doing a spacewalk, I'm in the zone. But every once in a while you can take a look up and take it all in and enjoy the experience."
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