NASA Pushes 97th Spacewalk to August 18

The spacewalk originally planned for this week has been pushed to Tuesday, August 18. NASA announced the new date on August 7, a day after astronauts Jessica Meir and Anil Menon spent 6 hours and 27 minutes outside the International Space Station. The reason: a carbon dioxide sensor in Menon’s spacesuit produced an unexpected reading near the end of the excursion.

We covered the preparations for that spacewalk when NASA announced work on the station’s seventh solar array and the S6 segment. Everything on that task list got done. What wasn’t on anyone’s list was rearranging the rest of August’s schedule once the suits came off.

What Meir and Menon did outside

The excursion wrapped up at 3 p.m. Eastern. It was Meir’s sixth spacewalk; for Menon, it was his first. By NASA’s count, it was the 281st spacewalk in the station’s assembly, maintenance and upgrade history, a tally that stretches back to the late 1990s.

The task was preparatory: the pair readied power channel 3B for a future roll out solar array, which NASA designates IROSA. The arrays themselves go up later, during one of the upcoming spacewalks.

Why the station needs more power

The IROSA arrays aren’t going up because the station is short on power for its experiments. NASA’s statement lists two purposes: powering critical systems, and a safe, controlled deorbit of the station.

That second point is what ties this seemingly routine job to the laboratory’s end of life. The solar arrays being prepared now need to keep working even once the station is guided downward, a phase in which losing power is not an option.

Does the reading mean the suit is faulty?

Not based on what’s been released so far. Menon reported no other issues during the excursion, and the sensor returned to normal readings as soon as the suit came off. Engineers on the ground are expected to spend the coming days assessing whether the suit needs to be swapped out before the next spacewalk.

NASA has not said what caused the reading, or whether the cause lies in the sensor itself, in the carbon dioxide removal system, or somewhere else. The decision on replacing the suit is also what will determine how much further the schedule slips.

The new schedule and the rest of the week

The next spacewalk, the 97th overall, is now set for August 18, with the crew swapping out an antenna used for communication with the ground, the one that carries high speed data between mission control and the station. Who will go out hasn’t been announced yet. The third spacewalk of the month remains scheduled for August 25 for now, leaving seven days between the second and third outings.

The rest of the crew kept to their usual work. Jack Hathaway practiced operating the Canadarm2 robotic arm, which supports spacewalks. European Space Agency astronaut Sophie Adenot trained in the EasyMotion-2 suit, which uses electrical impulses to trigger muscle contractions, then moved to the Columbus module to work with the E4D device, whose usefulness for long duration missions researchers are still evaluating.

The three cosmonauts of Expedition 75 had their own assignments:

• Andrei Fedyaev measured blood flow parameters using cuffs on his arm, wrist and fingers
• Pyotr Dubrov set up automated Earth photography and tested artificial intelligence tools
• Anna Kikina photographed potential equipment stowage sites from the Zarya module

None of this points to a problem with the spacesuit fleet as a whole. It comes down to one reading, on one suit, that stopped as soon as the suit came off. NASA said it will release more details on upcoming spacewalks early next week, and only then will it be clear whether August 18 is the final date.