Christina Koch and Jessica Meir are NASA astronauts living aboard the International Space Station. They were the 14th and 15th women, respectively, to conduct a spacewalk.

Astronaut Jessica Meir on the first all-female spacewalk Oct. 18. (NASA)

LOW-EARTH ORBIT — It’s tough being smaller in a big-suit world.

Aerospace is an industry that innovates with every leap, but what makes it so worth pursuing also makes it an endeavor with long development times. So when NASA designed new spacesuits in the 1970s after the Apollo missions, there were tradeoffs. Very few astronauts required a small suit, so given limited resources, the result was a spacesuit fleet that best fit larger bodies — typically male bodies.

But six years ago, before our astronaut class — the first class ever to be half women — stepped into our first spacewalk lesson, NASA made one thing very clear: Failure was not an option. We would be spacewalkers, and that meant all of us. Last month, that mantra rang true as the two of us embarked on the first spacewalk to be conducted with only women.

Meir outside of the International Space Station, with Earth 250 miles below. (NASA)

Nothing could have fully prepared us for what it would be like to float outside the space station. And even on one’s 23rd — or 217th — day orbiting the Earth, as was the case for us, the vast expanse of the cosmos is still a wonder.

The close quarters of the spacewalking suit are another story. The current suit is challenging to operate even when it fits perfectly. Its pressure resists movement, its bulkiness precludes dexterity, and its inertia demands significant upper body strength. When it is too big, these woes amplify. Not surprisingly, this drove persistent underrepresentation of women in spacewalking.

Although the first spacewalk by a man happened in 1965, it took until 1984 for a woman to step out into the vacuum of space. Since then, a total of 15 women have ventured into it. Of the 221 spacewalks at the International Space Station, 37 have included a woman, and now, just one has included two.

Those women who did break through before us became our heroines. As the sentiment and demographics of the astronaut corps moved toward gender equality, the range of suit sizes remained an anachronism tethered to the era of its birth by technical constraints and long redevelopment timelines. In this instance, the ramifications of a different epoch of space exploration diminished slowly because of technology, not intention.

Meir, left, and Christina Koch just before their joint spacewalk. (NASA)

We received nothing but support in our training at NASA. Mentors of all sizes lent their expertise. Classmates guarded against biases that any one set of physical characteristics was inherently better for spacewalking than any other. We knew that together, we could break down the faulty stereotypes built up by decades of limited-size spacesuits. Everybody was on board, from technicians who suited us up for practice runs to the leaders who prioritized our training. It was in their eyes, their work, their high-fives.

Yet we found that echoes of a bygone era could still stack the deck against smaller astronauts. Last spring, though two fully certified female spacewalkers were ready to go out the hatch to make history, suits that would allow them to do so were not. The sign of progress, however, was that this hitch resulted from a delayed cargo launch followed by an aborted crew launch — not from any lack of will.

In the same spirit that greeted our astronaut class at the door, NASA set to work reconfiguring the on-board suit fleet. When it was time for our spacewalks, two medium suits awaited us in the airlock.

One could say that the first all-female spacewalk was worth celebrating simply because it overcame history. It was the story of two girls who gazed at the stars with an improbable dream, who as women were given the “go” to egress the airlock. But there’s more than that.

Koch prepares to leave the airlock. (NASA)

The real achievement is the collective acknowledgment that it is no longer okay to move forward without everyone moving together. NASA’s mission is to answer humanity’s call to explore. If there is any part of humanity that’s not on that journey, we are not achieving our mission. The efforts to equalize exploration are what really ought to be celebrated.

NASA is in the habit of small steps and giant leaps. Our spacewalk was one; another will play out when the first woman and the next man set foot on the moon as part of the Artemis program in the 2020s. They will be wearing spacesuits designed with enhanced mobility and a size range that’s more extensive than ever before. With these suits, astronauts’ achievements will at last rely only on their own hard work and dedication.

We are entering a new era where we must commit to go boldly only if that means we all go, an era in which any person who dares to dream will have the opportunity to contribute. Our successes will be greater because not a single innovative idea will be turned away — that is what diversity and inclusion mean. And that is why a long-overdue all-female spacewalk so captivated the world it served.

Read more:

50 astronauts, in their own words

Mary Robinette Kowal: If space is the future, that future needs to include everyone

Lori Garver: Forget new crewed missions in space. NASA should focus on saving Earth.

Robert Gebelhoff: NASA’s latest gamble might not pay out. But it’s worth it anyway.

Robert Zubrin and Homer Hickam: We can build a colony on the moon. Let’s do it.