The first of two spacewalks planned during the STS-133 mission is at the heart of today's activities in space. Space shuttle Discovery's crew, now onboard the International Space Station, began their day with a wake-up call from Mission Control in Houston at 5:23 a.m. CST.
"Oh What a Beautiful Morning" by Davy Knowles & Back Door Slam was played for mission specialist Nicole Stott, who will choreograph the day's extravehicular activity (EVA) from inside the complex.
"It is once again a beautiful morning here in space," radioed Stott. "We're looking forward to EVA 1."
After an overnight campout in the station's Quest airlock, spacewalkers Steve Bowen and Alvin Drew will venture outside to begin their six and a hour EVA at 10:18 a.m. Bowen, as the lead spacewalker, will wear a suit with red stripes and Drew will wear an all-white spacesuit.
The spacewalk's objectives include installing an extension cable, a pump module vent tool, a camera wedge and extensions to a mobile transporter rail. The two spacewalkers will also store a failed pump module, relocate a tool stanchion and participate in an experiment to be exposed to space.
During the spacewalk, pilot Eric Boe will work to transfer more cargo from Discovery's middeck to the station. With over 2,000 pounds of equipment and supplies to move in total, these transfers began almost immediately after the shuttle arrived and will continue throughout the docked part of the mission until complete.
Running about 30 minutes ahead of schedule, astronauts Stephen Bowen and Alvin Drew switched their spacesuits to internal battery power at 9:46 a.m. CST, marking the official start to the first spacewalk of the STS-133 mission.
Bowen, starting his sixth career extravehicular activity (EVA), exited the International Space Station's Quest airlock first. As lead spacewalker, he is wearing the spacesuit with red stripes.
Drew, wearing an all-white spacesuit, is making his first spacewalk. He is the 200th person in history to work in the vacuum of space.
Credit: NASA TV
The spacewalkers first task is to run an extension cable, which will clear the way for the installation of the Permanent Multipurpose Module (PMM) delivered by space shuttle Discovery.
The J612 cable, which provides power to secondary airlock heaters, will be inaccessible after the PMM is installed. The extension cabe will make any future replacements of the system easier.
Installing the cable will take Bowen and Drew about 30 minutes. To do so, Bowen will remove dust caps from the cable and release some wire ties currently holding the J612 cable in place. Then, he will disconnect the original cable from the Unity node and connect the extension cable in its place, before tying down the extension cable.
Drew, meanwhile, will connect the extension cable to the original cable, which runs to the Quest airlock. He will also work to secure the cables in place.
Just before the spacewalk began, Bowen and Drew spoke with astronaut Tim Kopra, who originally was to have led today's EVA. Injured in a bike accident last month, Kopra was replaced by Bowen on Discovery's crew. Kopra helped re-plan the spacewalk for Bowen and is in Mission Control to lend his experience as needed.
"I'm really looking forward to working with you guys," radioed Kopra. "I'm sitting side saddle with [capcom Stan Love] and helping out where I can."
"Thanks Tim!" replied Bowen, while still inside the Quest airlock.
"Good to hear your voice Steve," said Kopra.
"It should be the other way around though," responded Bowen.
"You're a good man for the job," Kopra answered.
"All your good work coming to fruition here Tim," added Drew.
Spacewalkers Stephen Bowen and Alvin Drew completed their first task, installing an extension to the J612 power cable outside the Unity module. Without the extension, the cable would have been inaccessible after the Permanent Multipurpose Module delivered by space shuttle Discovery is installed to the International Space Station on Tuesday.
Next the spacewalkers will finish up work started by Expedition 24 flight engineers Tracy Caldwell Dyson and Douglas Wheelock moving a failed pump module to a more permanent storage location on the space station.
Credit: NASA TV
Riding the end of the space station's robotic arm, Bowen will move to the Payload Orbital Replacement Unit Accommodation, or POA, which is one of the robotic arm's "hands" used to temporarily store equipment. In this case, the equipment is the pump module that failed over the summer.
To remove the pump module from the POA, Bowen will install a handle on the module and then have Mission Control release the POA's hold on it. He'll then carry the module back to the stowage platform, which will be its long-term storage location.
While Bowen retrieves the module, Drew will collect from the port truss crew equipment and translation aid (CETA) cart a tool that will be used to remove remaining ammonia from the pump module.
Bowen and Drew will then work together to secure the module. Four bolts will be installed to hold it in place. They will also install the tool that Drew retrieved — called the vent tool — for use during the second spacewalk.
Spacewalkers Stephen Bowen and Alvin Drew completed stowing a failed ammonia pump module, the most time consuming activity planned during their six and a hour spacewalk.
Assisted by robotic arm drivers Scott Kelly and Michael Barratt, Bowen and Drew attached the 800-pound ammonia pump module to External Stowage Platform 2 on the outside of the Quest airlock. The failed pump module will remain there until it can be returned to Earth for engineering analysis at a future date.
The spacewalkers also installed a tool to vent the remaining ammonia from the pump module into space.
The pump module failed in July 2010 and was removed from its original truss location during an Aug. 11, 2010, spacewalk by Douglas Wheelock and Tracy Caldwell-Dyson. It had been temporarily stored on the mobile base system payload orbital replacement unit accommodation (POA) for about six and a half months.
With the pump module stowed, Bowen will climb off the station's robotic arm as Drew moves to a segment of the station's truss near the center of the system, the Z1 segment, where he'll fold back two flaps of insulation on a remote power control module, relocate a tool stanchion and retrieve another foot restraint, this one to store inside the airlock.
Credit: NASA TV
Afterward, Bowen and Drew will come back together to install a camera wedge on a video camera on the first starboard segment of the station's truss. The wedge will provide the camera the added clearance that it now needs given last Saturday's addition of the ExPRESS Logistics Carrier 4 (ELC4) nearby.
To install the camera wedge, Drew will remove the camera's stanchion by removing a bolt. The wedge will be secured to the truss using a bolt, and then the stanchion bolted back on the wedge. The task should take about an hour.
If time allows, Bowen and Drew will then move further down the starboard truss to the solar alpha rotary joint at the starboard three (S3) segment. There, they will install two extensions to the station’s mobile transporter track, which will allow the mobile transporter to travel the entire length of the track with the Crew Equipment Translation Aid (CETA) cart and still reach all worksites. Each extension (one on either rail of the track) will be secured by two bolts.
Credit: NASA TV
During the earlier pump module activities, the robotics work station in the space station's Cupola shut down, temporarily halting the work of station arm operators Scott Kelly and Michael Barratt. Rather than spend up to 30 minutes "rebooting" the system, Kelly and Barratt relocated to another work station in the Destiny lab to continue their support of the spacewalk.
The first spacewalk for space shuttle Discovery's STS-133 mission came to an end six hours and 34 minutes after it began at 4:20 p.m. CST.
Spacewalkers Steve Bowen and Alvin Drew, back inside the International Space Station's Quest airlock, completed all the tasks set out for them. They installed an extension cable clearing the way for the addition of the Permanent Multipurpose Module; stowed a failed ammonia pump module; installed a camera wedge; added extensions to a mobile transporter rail; and relocated a tool stanchion.
Bowen and Drew wrapped up their spacewalk with JAXA's "Message in a Bottle" educational experiment, exposing a metal cylinder to the vacuum of space in an effort to return some of space to the ground.
This was Bowen's sixth career spacewalk, bringing his total time working outside in space to 41 hours and four minutes. He now ranks 19th on the list of all worldwide astronauts and cosmonauts by time spacewalking.
Drew, completing his first spacewalk, became the 200th person in history to work in the vacuum of space since Russian cosmonaut Alexei Leonov made the first spacewalk in March 1965.
Today's excursion was the 154th spacewalk devoted to station assembly and maintenance, bringing that total to 967 hours and 39 minutes. It was also the 243rd spacewalk by U.S. astronauts.
Space shuttle Discovery has gained one more day in space before it will leave the International Space Station and return to Earth for the last time.
For now, that extra day — which becomes a new Flight Day 10 — will be used by the crew to set up the Permanent Multipurpose Module (PMM) delivered by Discovery. The astronauts are scheduled to attach the PMM to the station's Unity node on Tuesday.
That bonus day however, may permit for an historic "family portrait" to be taken of the station with its full fleet of international visiting vehicles — Discovery included. The plan for that photo opportunity, which calls for a Russian Soyuz to undock and back away while the station rotates below it, is still under review.
"We just wanted to let you know that for the mission plan your plus-one docked day is approved," radioed spacecraft communicator, or capcom, Stan Love in Mission Control to STS-133 commander Steve Lindsey and station commander Scott Kelly.
"The focus of that [extra day] will be PMM outfitting. We are still awaiting a formal decision on the [photo opportunity] flyaround. We expect that to come out of the Flight Day 6 mission management team meeting," added Love.
Discovery will now depart the space station on March 6, and land back at the Kennedy Space Center in Florida around 10:35 a.m. CST on March 8.
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