The iconic spacesuit worn by Neil Armstrong when he took his "one small step" on the moon was far from a simple garment. This meticulously crafted piece of technology was a vital lifeline, protecting the astronaut from the harsh conditions of space and the lunar surface. Its development, however, was a long and arduous process.
Before Armstrong set foot on the moon, the suit underwent numerous modifications and tests, travelling back and forth between Delaware and Houston. Just two weeks before launch, a zipper was even replaced. This highlights the immense effort and meticulous attention to detail involved in designing a spacesuit.
"It's very exciting to incorporate new ideas, but designing a spacesuit is truly an iterative process," explains Cathleen Lewis, curator of International Space Programs and Spacesuits at the Smithsonian Institution's National Air and Space Museum. "You don't want to take bold risks at the expense of human life."
Every spacesuit is essentially a miniature spacecraft, designed to provide communication, life support, and physical protection. Lunar spacesuits were particularly unique, needing to shield astronauts from extreme temperature fluctuations and the sharp lunar surface. They required flexibility for walking and collecting samples, along with portable life support systems. They even had to protect astronauts from microscopic meteorite particles travelling at incredible speeds.
The early spacesuits worn by Soviet cosmonaut Yuri Gagarin and American astronaut Alan Shepard in the 1960s were more like pressure suits, intended for emergency use only. The first true spacesuits, designed for extravehicular activity (EVA), were worn by cosmonaut Alexei Leonov and astronaut Edward White. These suits were painted a stark white to reflect the intense solar radiation.
"Both sides had tested these suits under the best simulated conditions they could create on Earth," says Lewis. "But things change in space."
The Apollo spacesuit was a complex creation, comprising over 20 layers and 12 different materials, including rubbery materials similar to those used in women's underwear for the joints. Many of these materials were readily available and had been used in various applications long before space exploration became a reality, such as Teflon, invented in 1938.
"Spacesuit engineers tend to be very conservative," says Lewis. "This is about preserving life, and they test their materials meticulously."
The development of spacesuits involved not just material selection but also ensuring their compatibility. Early suits combining brass zippers with rubber gaskets caused premature degradation. While Kevlar provided protection from space debris, it proved insufficient to prevent astronaut gloves from tearing on the sharp handholds of the International Space Station (ISS).
The tragic Apollo 1 test mission highlighted the limitations of the fabric used at the time, as it had a low melting point. This incident led to a change in material selection and emphasized the importance of testing every aspect of the suit.
"They stick to what they know and what works," Lewis says. "They make iterative changes using new combinations of materials."
Every new material undergoes rigorous testing, including microscopic inspections, X-ray analysis, and even simulated projectile impact testing. After the spacesuits are constructed, manufacturers like ILC even employ human testers to put them through their paces, "giving it a workout that it would get over its lifetime," according to Lewis. This involves a range of movements like flexing, lunging, and squatting.
"It's consistency and constant vigilance," says Lewis. "It's not as dramatic as someone jumping into a spacesuit and just leaping out into space."
As NASA prepares for its return to the moon after more than 50 years, it continues to refine its spacesuits, incorporating lessons learned from its long history. One focus is on creating suits that can be adapted to fit and function for everyone, regardless of their size.
"This doesn't mean they'll all be the same," Lewis clarifies. "But the essential operations of the suit will be consistent across the board."
Another significant challenge NASA faces is the rising cost of space exploration. This becomes more complex as NASA navigates the market with new contractors, such as Axiom and SpaceX.
Even seemingly simple challenges remain, such as the gloves worn by astronauts. While NASA has addressed the problem of tearing gloves, it has yet to create a glove that perfectly protects and insulates astronauts' hands while allowing for free movement. This is a problem that has plagued engineers for generations.
"We haven't figured out a way to replicate in a spacesuit glove what is so essential to us as human beings, and that's the ability to use our hands," says Lewis. "Whether we'll be able to do it, I don't know. The magic of obtaining the right material may still come."
The development of spacesuits is an ongoing journey of innovation and meticulous testing. Each new generation of suits represents a leap forward, pushing the boundaries of what is possible in space exploration. As humans venture further into the cosmos, these protective garments will continue to evolve, ensuring the safety of astronauts and paving the way for new discoveries.
