At 6:54 a.m. CDT Monday, Garrett Reisman and Steve Bowen switched their spacesuits to battery power, signifying the start of their planned 6.5 hour spacewalk, the mission's first of three. Atlantis' pilot Tony Antonelli inside the International Space Station (ISS) is choreographing the two spacewalkers' activities and communications between them and Mission Control in Houston.
The space shuttle crew awoke at 2:20 a.m. to Matt Maher's "Alive Again" for mission specialist Mike Good.
"Hey, good morning Houston," radioed Good, the STS-132 mission's third spacewalker. "It's great to wake up here in space again. We're looking forward to another beautiful day docked to the International Space Station."
Good's fellow two spacewalkers are focusing today on the installtion of a back-up communications antenna and a work platform onto the station's Canadian-built robot.
Credit: NASA TV
The first task of the spacewalk is the installation of a back-up Ku-band antenna known as the SGAnt or Space-to-Ground Antenna. Reisman's and Bowen's work begins at the mobile transporter to remove the SGAnt, then Reisman will hand carry the boom and antenna to its installation point on the Z1 truss.
Bowen will meet Reisman there to attach the antenna, connect its power and data cables, and remove insulation. During that time, Reisman will travel on the station's robotic arm, driven by STS-132 mission specialist Piers Sellers, to retrieve the antenna dish and bring it to the worksite for installation. Time permitting, Bowen will install a heat shield and remove position locks on the antenna.
Reisman will then again return to the Integrated Carrier Cargo to collect the Canadian robot Dextre's storage platform. He and Bowen will meet at Dextre's worksite atop the Destiny laboratory to attach the platform to the robot. If possible, they will also install a maintenance tether and connect two electrical fuses.
The final task will have Bowen traverse to the end of the port, or left side, truss, to loosen bolts on the six batteries that will be replaced in the later spacewalks, a task originally scheduled for the STS-131 mission in April but deferred due to the possibility of an electric shock hazard involving the mini work stations attached to the spacewalkers' suits. Bowen's and Reisman's mini work stations have been insulated to avoid the risk.
Lead for this spacewalk, Reisman is wearing a spacesuit with no stripes. Bowen' spacesuit is marked with a red stripe.
Just as spacewalkers Steve Bowen and Garrett Reisman completed their installation of a back-up antenna boom, the failure of one of the station's three command and control (C&C) computers, or as they are sometimes referred to, MDMs for multiplexer-demuliplexer, caused the astronauts to pause their work.
"We can't have [Bowen] do the Z1 connectors until we verify that the inhibits are still in place. We need the C&Cs back to do that," capcom Steve Swanson advised, referring to the antenna's power connectors that Bowen was next to attach. "For everyone inside, the rack power switches are inop[erational] at this time and it should be about five more minutes for the video system to be back up and operational so we can get robotics going."
The C&C computers are configured such to automatically transition in the case of a failure from the primary computer to a backup. That transition caused a temporary loss of power to some station systems, including the rack power switches and video from the robotic arm. Mission Control was ensuring protective measures were still in place before the spacewalkers connected the cables to the new Space-to-Ground Antenna.
Credit: NASA TV
During the down time, pilot and spacewalk choreographer Tony Antonelli assured Mission Control he had the spacewalkers occupied.
"I've got plenty for 'Steve-O' [Bowen] and I am keeping 'Big G' [Reisman] entertained out the window."
After about 30 minutes, with the robotic arm's video re-routed and power inhibits verified, the spacewalkers resumed their work. The cause of the MDM transition is yet unknown.
Five hours into their planned six-and-a-half-hour spacewalk, Steve Bowen and Garrett Reisman installed a new SGAnt or space to ground antenna, backing up the Ku-band system first attached to the International Space Station during STS-92 in 2000, but ultimately had to leave antenna bolted and tethered due to concerns by Mission Control over its stability.
After adding a boom to support the new antenna and taking a pause due to a command and control computer transition inside the station, Bowen began hooking up power connectors while Reisman retrieved the new six- foot dish from the Integrated Cargo Carrier launched by Atlantis.
At one point, Bowen had nothing to do but wait for Reisman to arrive with the dish.
"I don't know what else I can do," said Bowen.
"You should enjoy being in outer space, on a spacewalk, with a camera and a view," advised Tony Antonelli, the IVA or spacewalk choreographer.
"I guess I could do that," replied Bowen with a chuckle.
Credit: NASA TV
The spacewalkers were soon both busy though, working on attaching the dish to the antenna's boom. Even after the two assemblies were bolted, the astronauts reported seeing a gap between the dish and boom.
While Mission Control assessed the gap, Bowen and Reisman worked to latch a stubborn power connector.
After trying to force the connector's halves together and reporting seeing fine metal shavings floating away, the spacewalkers proposed waiting for the sun to warm and expand one half while the other was kept shadowed by a glove.
"Okay, here comes the sun," said Bowen.
"There it is," he announced minutes later, as the connector latched. "Woo-hoo!"
"Good work everybody," radioed Mission Control. "That's a good job waiting for the Sun, too. That was a good plan."
Bowen next wrapped the boom with a small insulating blanket and began to loosen gimbal locks, the last of the tasks before the antenna could be activated, when the decision was made to have him re-engage the bolts and further tether the antenna to the station's truss in light of the loose fit between the dish and the boom.
Running about two hours behind schedule but with a one-hour extension possible, Reisman turned his attention to retrieving a tool platform for the Canadian Dextre robot while Bowen returned to the airlock to recharge his oxygen supply. He then joined Reisman outside the Destiny laboratory to install Dextre's enhanced orbital replacement unit temporary platform.
Spacewalkers Garrett Reisman and Steve Bowen completed the first of three spacewalks planned for the STS-132 mission, beginning the Quest airlock's repressurization at 2:19 p.m. CDT, 7 hours and 25 minutes after their planned 6.5-hour excursion got underway.
Following their installation of a new back-up space-to-ground antenna for the station, the two astronauts focused on bolting down a tool platform on the Canadian robot Dextre. The two were able to tighten three of the ORU platform's four bolts; the stubborn fourth was ultimately deemed fine as-is by Mission Control.
Reisman finished by cleaning up the Destiny laboratory's Dextre worksite while Bowen traversed to the end of the port, or left, side truss to loosen the solar array batteries that will be replaced on the mission's second and third spacewalks.
The spacewalkers then took inventory of the tools they brought with them outside and made their way back into the airlock.
Credit: NASA TV
This was the 237th spacewalk conducted by U.S. astronauts, the 144th supporting station assembly and maintenance, the second for Reisman and the fourth for Bowen.
As STS-132 mission specialists Garrett Reisman and Steve Bowen were wrapping up their seven hour, 25 minute spacewalk, the first of three planned extravehicular activities (EVAs) for the mission, flight controllers reported that space shuttle Atlantis' arm had successfully grappled the Russian Mini-Research Module-1 (MRM-1) in the payload bay. The 19.7- foot module, named Rassvet, is scheduled to be installed on Tuesday on the International Space Station's Zarya service module.
Atlantis' astronauts went to sleep at 5:50 p.m. CDT. They're scheduled to begin Flight Day 5 at 1:50 a.m. Tuesday.