NASA astronauts Mike Hopkins and Victor Glover took a spacewalk Saturday outside the International Space Station to upgrade the lab’s communications and cooling systems. The walk, which took place about 250 miles above earth, lasted nearly seven hours.
Spacewalking astronauts had to take extra safety precautions after possibly getting toxic ammonia on their suits from the International Space Station’s external cooling system.
Victor Glover and Mike Hopkins had no trouble removing and venting a couple of old jumper cables to remove any ammonia still lingering in the lines. But so much ammonia spewed out of the first hose that Mission Control worried some of the frozen white flakes might have gotten on their suits.
The first task on the agenda was to safely vent the two ammonia jumpers, used for loading coolant in the station’s thermal control system and for helping track down leaks. The jumpers were located on the far left end of the lab’s solar power truss, a segment known as port 6, or P6.
Even though the stream of ammonia was directed away from the astronauts and the space station, Hopkins said some icy crystals may have contacted his helmet. As a result, Mission Control said it was going to “be conservative” and require inspections.
NASA did not want any ammonia getting inside the space station and contaminating the cabin atmosphere. The astronauts used long tools to vent the hoses and stayed clear of the nozzles, to reduce the risk of ammonia contact.
After confirming no contamination with ammonia ice crystals, the spacewalkers stowed one jumper on the P6 segment for any future troubleshooting that might be needed on that side of the station while the other was mounted outside the airlock for use if needed later on the right side.
Struggling with balky electrical connectors, Hopkins managed to plug in and secure three of four thick power and data cables needed by a European experiment platform during a challenging spacewalk, leaving one cable for additional troubleshooting.
An external experiment platform known as Bartolomeo was attached to the forward side of Columbus earlier, but spacewalkers had problems completing electrical connections during an earlier outing. Hopkins struggled to complete the job Saturday, but eventually succeeded with three of four cables.
Mission Control said the astronauts had already spent enough time in the sunlight to bake off any ammonia residue from their suits. Indeed, once Glover and Hopkins were back inside, their crewmates said they could smell no ammonia but still wore gloves while handling the suits.
Glover replaced a wireless camera transceiver and attached a stiffener to a flexible thermal cover on the Quest airlock’s outer hatch. He complained of an unusual irritation that briefly caused his right eye to tear up, but said repeated blinking seemed to help.
Hopkins also reconfigured a HAM radio antenna on the European Columbus module that failed to work correctly after a recent upgrade and both spacewalkers began work to route two Ethernet cables that eventually will be part of an expanded external Wi-Fi network.
The spacewalk came to an end at 3:01 p.m. for a duration of six hours and 47 minutes. Total station spacewalk time through 237 excursions now stands at 1,491 hours and 54 minutes, or 62.2 days.
NASA’s Shane Kimbrough and France’s Thomas Pesquet tackled the second in a series of powerful solar wings that should keep the space station running the rest of this decade, as space tourism ramps up with visitors beginning in the fall. Kimbrough and Pesquet are two months into a six-month mission. Two other Americans are aboard the space station, along with one Japanese and two Russians.