369 DAY IN THE LIFE: WHEN MAJOR ANOMALIES OCCUR CHAPTER 20 issues that were resolved and what will be done on the EVA had been summarized. However, some overhead in preparing is needed to frame the situation for the public, just as any presentation takes some work (Figure 10). Figure 10. A press conference held December 18, 2013, prior to the first spacewalk. From left to right: NASA moderator Josh Byerly, ISS Program Manager Mike Suffredini, Flight Director Dina Contella, and Lead EVA Officer Allison Bolinger. An ISS Mission Management Team (IMMT) meeting was held on Friday to determine the readiness to proceed with the spacewalks (aka, a “Go or no Go” poll). The Team 4 lead flight director briefed the IMMT on all the completed work and conclusions they had reached, and the international partners and representatives from all of the key organizations reported on their readiness and agreement. The IMMT then decided how to proceed forward. The EVA timeline of events was ready to go. Mastracchio would “ride the arm” (i.e., put his boots into a foot restraint on the robotic arm) and be the one to work with the difficult fluid QDs. If the QD operations went smoothly, he could move on to tasks planned for the second spacewalk to remove the massive failed Pump Module and temporarily stow it on the Mobile Remote Servicer Base System. Hopkins was going to “free float,” moving himself by grasping handrails and assisting Mastracchio. Wakata was the primary robotic arm operator, with Kotov helping him at the Robotic Workstation. As the EVA approached, a concern surfaced that the Interface Heat Exchanger for the Columbus module (similar to the Lab version, shown in Figure 2) might have been accidentally exposed to freezing temperatures that could result in an ammonia leak into the internal thermal cooling system after activation of the new Pump Module during repressurization of the external loop. The concern was raised based on thermal analysis, not actual temperature telemetry, so the team was trying to work through whether this was a real concern or if something was slightly wrong or overly conservative in the analysis. The team was also working on a Loop A repress procedure that accounted for this potential problem with the Columbus heat exchanger. However, everyone agreed that a solution would be found and the EVAs should continue. The ISS Mission Management team agreed on Friday morning that everything was ready and the team was Go for the EVA on Saturday. To prevent fatigue during the critical EVAs, almost everyone working in the control center for Saturday’s EVA was encouraged to take Friday off to rest. Saturday, Dec 21, 2013— The First EVA (ISS EVA 24) The moment had arrived for the first EVA. The night before, the lead EVA officer and flight director for the spacewalk marked up their procedures with notes such as “discuss EMU consumables” at various points, to agree in advance how often they would make standard calls and generally study what information exchange would be necessary. The team was fairly well rested and ready to go. The crew worked efficiently that morning in “EVA prep” and prebreathe, with Wakata and Tyurin helping to suit up Mastracchio and Hopkins and allow them to purge the nitrogen from their blood by breathing pure oxygen before depressing the airlock (see Chapter 17). The EVA crew members tethered themselves