The historic all-female spacewalk has been cancelled. NASA announced earlier this week that Anne McClain, who was going to float outside the International Space Station with Christina Koch, will be replaced by Nick Hague. The problem? The space agency said that there aren’t enough spacesuits onboard the ISS to fit both women
While it may seem like a mistake that could have easily been fixed, the issue is much more complicated. When NASA began launching astronauts to space, women weren’t wearing them. In the 1960s, spacesuits were custom-made for astronauts, all of whom were male. However, tailoring was expensive and time-consuming: in the 1970s, NASA switched to a cookie-cutter approach by developing separate pieces for the arms, legs and torsos, to be mixed and matched. The spacewalking suits, called extravehicular mobility units, came in five sizes, ranging from extra-small to extra-large.
Problem solved, right? Not exactly. “Some groups initially assumed that women could fit in the same sizes as small men—or at worst, that some of the men’s sizes would have to be scaled down proportionately to fit women,” wrote NASA design engineer Elizabeth Benson in a 2009 paper on spacesuit design.
The approach did not take into consideration the differences in body shapes of men and women. “For the same height and weight, women can have significantly wider hips and narrower shoulders than men,” Benson wrote. “If, for example, a one-piece coverall designed for a man is meant to fit at the shoulders and the hips, then one of these fit areas is likely to be compromised for a woman.”
While a piece of clothing that is too large is not a hindrance on Earth, having extra room in a spacesuit makes moving about more difficult. “As a woman, doing spacewalks is more challenging mostly because the suits are sized bigger than the average female,” said NASA astronaut Peggy Whitson, who completed an unprecedented number of spacewalks – ten in total – by a female astronaut.
In the 1990s, amidst budget cuts, extra-small and small sizes were eliminated. And while most astronauts could fit in a size medium or large, some faced a problem. “People my size are in fourth grade. Literally, I mean, some fourth graders are bigger than me,” said five-foot-tall NASA astronaut Nancy Currie in a 2006 interview. These restrictions affected the type of work astronauts could do on the ISS. After the US shuttle program ended in 2011, more restrictions followed: in addition to qualifications and experience, physical size of astronauts become a factor.
Back to this week’s conundrum: the ISS currently has six people on board, alone with six spacesuit torso pieces: two in medium, two in large, and two in extra-large. Only some of them are ready for spacewalks. McClain had trained on the ground in both medium and large, and during last week’s spacewalk with Hague, she wore the medium torso. Incidentally, it was the same size Koch had planned to use.
“We do our best to anticipate the space-suit sizes that each astronaut will need, based on the space-suit size they wore in training on the ground, and in some cases—including Anne’s—astronauts train in multiple sizes,” said NASA spokesperson Brandi Dean. “However, individuals’ sizing needs may change when they are on orbit, in response to the changes living in microgravity can bring about in a body. In addition, no one training environment can fully simulate performing a spacewalk in microgravity, and an individual may find that their sizing preferences change in space.”
Making adjustments to the spare medium torso would take a lot of prep work, so NASA changed the spacewalk lineup instead.
NASA’s inspector general reported in 2017 that the spacesuits “have far outlasted their original 15-year design life.” In fact, astronauts still use spacesuits that are 40 years old, as NASA has not made any changes since they were first designed. While the agency has spent nearly $200 million on spacesuit development for future missions, those suits will be different because they need to adapt to the specific conditions of the moon and Mars.
In the meantime, the agency is still “years away from having a flight-ready spacesuit capable of replacing the EMU or suitable for use on future exploration missions,” according to the report. With more female astronauts than ever, it seems only logical that NASA should allocate some of the funding to developing updated, well-fitting spacesuits available for its astronauts.
Photo credit: NASA