The first all-female spacewalk was a landmark event in space exploration history, occurring on October 18, 2019, when NASA astronauts Christina Koch and Jessica Meir stepped outside the International Space Station (ISS). This milestone addressed historical limitations in spacesuit design and marked a critical shift toward gender-neutral accessibility in extravehicular activities (EVAs) and upcoming lunar missions.
The Significance of All-Female Extravehicular Activities
The term "all-female spacewalk" refers to an Extravehicular Activity (EVA) where every astronaut outside the spacecraft is a woman. While women have been performing spacewalks since 1984, they were almost exclusively paired with male colleagues. The transition to all-female teams was not merely a symbolic gesture; it represented a resolution to long-standing logistical and technical barriers within NASA’s hardware inventory.
By 2026, the concept of the all-female spacewalk has evolved from a groundbreaking "first" into a recurring operational reality. As NASA prepares for the Artemis missions—which aim to land the first woman and first person of color on the Moon—the lessons learned from the initial all-female EVAs on the ISS continue to influence how suits are designed, how crews are trained, and how mission architecture is planned.
Historical Context: Breaking the Glass Ceiling in Orbit
To understand the weight of the all-female spacewalk, one must look at the history of women in space. Svetlana Savitskaya became the first woman to perform an EVA in 1984, followed closely by Kathryn D. Sullivan later that same year. Despite these early successes, the frequency of women participating in EVAs remained low for decades.
The primary bottleneck was not a lack of qualified female astronauts, but rather the physical equipment. The Extravehicular Mobility Units (EMUs) used on the ISS were designed in the 1970s. At that time, suit sizes were limited to medium, large, and extra-large. The "small" size was discontinued due to budget cuts, which effectively sidelined many women (and smaller-statured men) from EVA eligibility.
The March 2019 Suit Controversy
A significant turning point occurred in March 2019. NASA had initially planned an all-female spacewalk with Anne McClain and Christina Koch. However, after McClain’s first spacewalk in a different crew configuration, she realized that a "medium" torso was the only size that allowed her the necessary range of motion to work safely. Because the ISS only had one medium-sized torso ready for use at that moment, the crew assignments were changed, and a male astronaut took her place.
This incident sparked a global conversation about gender equity in engineering. It highlighted how the "default" male body type had dictated the design of critical life-support equipment. NASA’s subsequent efforts to prepare a second medium torso set the stage for the successful milestone later that year.
The Landmark Mission: October 18, 2019
On October 18, 2019, Christina Koch and Jessica Meir finally made history. The duo exited the Quest airlock to replace a failed Battery Charge/Discharge Unit (BCDU). This component is essential for regulating the amount of charge put into the batteries that collect energy from the station’s solar arrays.
Technical Objectives and Execution
The mission lasted seven hours and 17 minutes. While the primary task was the BCDU replacement, the astronauts also performed several "get-ahead" tasks, which are lower-priority maintenance items completed if time permits. The operation was managed by a diverse team on the ground, including NASA’s Mission Control in Houston, where astronaut Stephanie Wilson served as the primary communicator (CAPCOM) between the ground and the EVA crew.
The success of this mission proved that the operational hurdles were purely technical. Once the hardware—specifically the suit sizing—was addressed, the execution was flawless. Koch and Meir went on to perform two more all-female spacewalks in January 2020, solidifying their roles as pioneers in orbital maintenance.
Technical Requirements for All-Female Spacewalks
Performing a spacewalk is among the most physically demanding tasks an astronaut can undertake. It is often described as running a marathon while using only your hands. For women to lead these missions, several technical and physiological factors must be managed.
Anthropometry and Suit Fit
Spacesuits act as pressurized "mini-spacecraft." If a suit is too large, the astronaut must fight against the pressure of the suit to reach tools or move their arms, leading to rapid fatigue and potential injury.
- The Hard Upper Torso (HUT): This is the rigid core of the suit. Ensuring a variety of HUT sizes is critical for enabling women of various heights to maintain a proper center of gravity.
- Gloves: EVA gloves are custom-sized. Precise fit is vital because the hands do 90% of the work during a spacewalk. Lack of dexterity in a poorly fitted glove can lead to "fingernail delamination" and extreme bruising.
Physical Training and Conditioning
Astronauts train for years at the Neutral Buoyancy Laboratory (NBL) in Houston. The NBL is a massive pool containing a full-scale mockup of the ISS. Training in the pool simulates the microgravity environment. Women often utilize different biomechanical strategies than men to leverage their body weight and strength, focusing on core stability and precise tool placement to overcome differences in upper-body raw power.
The Evolution of Spacesuit Technology into 2026
As of 2026, the hardware limitations of the 1970s are being phased out. The development of the Axiom Extravehicular Mobility Unit (AxEMU) has revolutionized the ability for all-female crews to operate in space.
| Feature | Legacy EMU (ISS) | AxEMU (Artemis/Modern ISS) |
|---|---|---|
| Size Range | Limited (M, L, XL) | Highly modular; fits 90% of the population |
| Mobility | Rigid joints; difficult to walk | Enhanced hip and knee joints for lunar walking |
| Entry Method | Waist-entry (two pieces) | Rear-entry (allows for easier donning/doffing) |
| Maintenance | Requires ground-based refurbishment | Designed for long-duration, in-situ maintenance |
| Primary Use | Microgravity (ISS) | Lunar Surface and Microgravity |
The AxEMU, designed by Axiom Space in collaboration with NASA, uses a modular design that allows the torso, limbs, and boots to be swapped out easily. This ensures that no astronaut is ever excluded from a mission due to a "medium" or "small" suit shortage.
Challenges and Safety Protocols in Deep Space EVAs
As we look toward the Artemis missions in 2026 and beyond, the risks associated with all-female spacewalks (and all EVAs in general) shift from the ISS environment to the lunar environment.
Radiation Exposure
Women generally have lower lifetime limits for radiation exposure than men, primarily due to the higher risk of certain cancers, such as breast and ovarian cancer. However, recent NASA studies have moved toward a more individualized and equitable "universal limit" of 600 millisieverts (mSv) for all astronauts. This change ensures that female astronauts have equal opportunities for long-duration missions to the Moon and Mars without being restricted by outdated physiological models.
Dust Mitigation
On the lunar surface, "all-female moonwalks" will face the challenge of lunar regolith—microscopic, glass-like dust. This dust is abrasive and can degrade suit seals. The modern suits used in 2026 feature specialized coatings and "suit ports" that minimize the amount of dust brought into the pressurized habitat.
The Psychological and Cultural Impact
The visibility of all-female spacewalks serves a dual purpose. First, it normalizes women in high-stakes technical leadership roles. Second, it inspires a new generation of scientists and engineers. When Christina Koch and Jessica Meir spoke to students from orbit during their 2019 walk, they emphasized that their success was a testament to decades of work by women who came before them.
In 2026, we see the results of this "representation effect." Enrollment in aerospace engineering programs has seen a marked increase in female students, and the current astronaut corps is more demographically balanced than at any point in NASA's history.
Frequently Asked Questions
Why did it take 35 years after the first woman walked in space for an all-female spacewalk to happen?
The delay was primarily due to hardware limitations. The Extravehicular Mobility Units (EMUs) used on the ISS were built decades ago and were not optimized for smaller frames. Additionally, the pool of female astronauts was smaller in previous decades, making the statistical likelihood of an all-female pairing lower. It wasn't until NASA expanded suit-sizing availability and increased the diversity of its astronaut classes that an all-female EVA became operationally feasible.
Was the 2019 all-female spacewalk a publicity stunt?
No. The spacewalk was a critical maintenance mission required to repair the ISS power system. While the timing of the pairing was notable, the tasks performed—replacing a failed BCDU—were essential for the continued operation of the space station. NASA crews are assigned based on training, readiness, and technical proficiency; the all-female pairing was a result of having two highly qualified astronauts ready for the task.
How long does an all-female spacewalk typically last?
Most ISS spacewalks, regardless of the crew's gender, last between 6.5 and 8 hours. The duration is limited by the life-support capabilities of the spacesuit, including oxygen supply, battery power, and the capacity of the Carbon Dioxide removal system. The 2019 all-female spacewalk lasted 7 hours and 17 minutes.
What is the most difficult part of a spacewalk for female astronauts?
The most significant challenge is often the physical toll on the hands and forearms. Because the suit is pressurized, every time an astronaut closes their hand to grab a tool, they are fighting against the internal air pressure of the glove. Because women often have smaller hands, getting a perfect glove fit is essential to prevent injury and maintain the stamina needed for an 8-hour shift.
Are there more all-female spacewalks planned for 2026?
With the ISS still operational through 2030 and the Artemis program in full swing, all-female pairings have become a standard part of crew rotations. As of 2026, NASA and its international partners (ESA, JAXA, CSA) regularly assign crews based on specific mission needs, and all-female EVAs are now viewed as a routine operational capability rather than a rare event.
Future Outlook: From Orbit to the Lunar Surface
The success of all-female spacewalks on the ISS has paved the way for the ultimate goal: the first woman on the Moon. As of 2026, the Artemis program is the primary driver of EVA innovation. The lessons learned about suit fit, ergonomics, and crew dynamics during the Koch and Meir missions are directly influencing the design of the lunar habitats and the lunar terrain vehicles.
Space exploration is moving toward a future where "all-female" is no longer a qualifier, but a standard configuration. The focus has shifted from whether women can do the job—which was proven decades ago—to ensuring that the technology and systems they use are designed to maximize their performance.
Practical Recommendation: For those interested in tracking current and upcoming spacewalks, the NASA EVA Management Office provides live updates and technical briefings. If you are a student or professional in a STEM field, consider exploring the NASA SuitUp Challenge, which invites public participation in solving the very design problems that once hindered female participation in spacewalks.
