Two astronauts walked outside the confines of the International Space Station (ISS) this Friday, marking the first of three spacewalks that are scheduled to take place in 2017. European Space Agency astronaut Thomas Pesquet began the spacewalk, which started at 7:22 a.m. EDT (1122 GMT), and NASA astronaut Shane Kimbrough followed. The astronauts parted ways, and each of them conducted a different task orbiting the ISS.
The spacewalk was live streamed, and people were able to see the astronauts performing their tasks. Pesquet, who is also a flight engineer was busy the entire spacewalk, while Kimbrough, commander of the station’s Expedition 50 crew, had more time to spare.
Spacewalks will prepare dock for commercial spacecraft
The goal of the first spacewalk was to prepare the ISS for the upcoming docking of commercial spacecraft, including SpaceX’s Crew Dragon and Boeing’s CST-100 Starliner. The next spacewalk is scheduled for March 30, and the astronauts will continue preparing the space station for the docking. During the second spacewalk, Pesquet and NASA astronaut Peggy Whitson – who assisted the two astronauts on Friday’s journey – will connect PMA-3 to the Harmony module. The Harmony module is the location where NASA wants to install another International Docking Adapter in 2018, for commercial spacecraft only.
“PMA-3 provides the pressurized interface between the station modules and the docking adapter,” said NASA in a statement, according to Space.
Kimbrough’s tasks during the spacewalk started by replacing an old external backup computer dubbed Multiplexer-Demultiplexer (MDM) with a new one in the Starboard-0 (S0) truss. The new computer is called the Enhanced Processor and Integrated Communications (EPIC MDM). The EPIC MDM has an upgraded software, able to sustain the new docking adapter. The astronaut replaced both computers and had time to drop them off at the airlock on the space station before going to PMA-3. Kimbrough is also scheduled to replace another old MDM computer with a new EPIC MDM on March 30.
Pesquet’s task was a little different. He was in charge of performing maintenance to the space station, unrelated to PMA-3. Firstly, he took a foot restraint placed on an external stowage platform. After taking the foot restraint, he headed to the P1 truss, to look into a suspected ammonia leak, located in a radiator valve in the cooling system.
“We’ve been tracking a small rate of leakage from that ammonia system over the last year or so, and our external robotic systems have determined a most likely location where the system may be leaking,” explained NASA Flight Director Emily Nelson at the news conference, according to Space. “It’s time to get crewmember eyeballs on the area and get a human evaluation to determine whether we have any damage to the system.”
Pesquet spent two hours looking for the ammonia leak but found no signs. The astronaut took a Go-Pro to film the P1 cooling system The second, so ground crews can investigate if there is a leak and consequently, the source. He had pushed the hoses of the radiator valve in the cooling system to let loose any flakes of frozen ammonia.
The second spacewalk is scheduled for March 30
After the flight engineer had found no sign of ammonia, they went on to the station’s Special Purpose Dexterous Manipulator (Dextre). Dextre is an extension of the robotic arm named Canadarm2. The robotic arm was in need of maintenance, and Pesquet rubbed lubricant to the latching end effector (LEE). LEE is the hand of the robotic arm. He spent four hours applying the lubricant to LEE. Whitson, who was inside the space station, controlled Dextre and brought it closer to Pesquet, who was having trouble reaching the robotic arm even with the extended foot restraint he took from the stowage platform.
Kimbrough’s tasks allowed him to manage his time better, and he assisted Pesquet’s work by grabbing a bag of tools and taking them to his colleague. That action saved precious time for Pesquet, who was too busy with the maintenance of the robotic arm. Kimbrough also made a trip to the Japanese Kibo module and replaced two cameras that had broken lights. The lights can still be used in the future, once they are fixed inside the station.
The two astronauts headed back to the International Space Station at 1:58 p.m EDT (1758 GMT) after concluding their assigned tasks. With Friday’s spacewalk, Kimbrough has finished five spacewalks and has a total of 32 hours doing extravehicular activities (EVAs). Pesquet has completed two spacewalks – counting Friday’s – and has 12.5 hours of EVA hours.
NASA marked the mission as a success, despite a few mishaps. On the March 30 spacewalk, Kimbrough will add more hours to his EVAs, and Whitson will join him. Pesquet will assist them from inside the ISS.