NASA reschedules ISS spacewalk after astronaut experiences 'spacesuit discomfort'

NASA has picked a new date for the spacewalk that was postponed last weekend due to "spacesuit discomfort."

NASA astronauts Tracy Dyson and Matt Dominick were set to perform the International Space Station's (ISS) 90th extravehicular activity (EVA 90) on June 13, and had already been outfitted with the majority of their spacesuits when the cancellation call came through about an hour before egress. "When Matt was suited, he experienced some discomfort in the suit," said NASA's ISS program manager Dana Weigel, during a press call Tuesday (June 18).

"We couldn't resolve it that day," Weigel said. She explained that potentially needing to cancel the EVA once already underway could leave work outside the station in an unfinished configuration, and posed an unnecessary risk to astronaut safety. Now, Dyson is scheduled to suit-up for the same EVA on June 24, but this time with NASA astronaut Mike Barratt.

EVA 90 was the first in a series of three EVAs scheduled for this summer, but last week's delay means ISS Expedition 71 crew members will now have to complete the work in only two EVAs. According to Weigel, the station's oxygen supply was allocated for three spacewalks, but nearly a full EVA's worth of oxygen was consumed during the crew's preparations last week. "You use a lot during the beginning portion of an EVA, as you're doing the pre-breathe activities," she explained.

Related: NASA calls off spacewalk at International Space Station due to 'spacesuit discomfort'

As for the switch from Dominick to Barratt, "[NASA] had already planned for Mike (Barratt) to go out, so we had a suit ready for him," Weigel said on the call, adding, "instead of taking the extra time with all the other activities going on onboard around Starliner, we decided it just made sense to go ahead and use Tracy and Mike, who were going to do EVAs anyway in this series."

Among the many goings-on aboard the ISS is Boeing Starliner's Crew Flight Test (CFT), with NASA astronauts Butch Wilmore and Suni Williams. The pair were supposed to return to Earth a week after their June 6 arrival to the space station, but the return date has now been shifted several times, in part because of the station's busy schedule. NASA had originally pushed back Starliner's departure to June 22 to accommodate EVA activities, but is now targeting now earlier than (NET) June 26 for the mission's return.

Dyson and Barratt's June 24 EVA will complete the tasks planned for last week's spacewalk, which included retrieving a failed S-band RF group communications box and swabbing exterior station surfaces to collect samples for a study of microorganisms in extreme microgravity environments. The second EVA of the summer's series is scheduled for July 2, and will focus on replacing the station's gyroscope assembly, relocating an antenna, and completing preparatory tasks for upcoming enhancements to the Alpha Magnetic Spectrometer (AMS).

EVA 90, with Dyson and Barratt, is scheduled for 8:00 a.m. EDT (1200 GMT) on June 24, and will be covered live on the Space.com homepage, courtesy of NASA, and live on the space agency's website, beginning at 6:30 a.m. EDT (1030 GMT). Crewmember selection for the second EVA, according to Weigel, will take place only after the completion of the first, and is scheduled for 9:00 a.m. (1300 GMT) July 2, with coverage that day beginning at 7:30 a.m. EDT (1130 GMT).