"Space Technology Enriches Our Lives": An Expert Unpacks the Evolution and Future of Space Suits

Set for mid-2027, the Artemis program is an international project aiming for the first crewed lunar landing since the Apollo era. Two Japanese astronauts are slated to join the mission. The key to its success? A state-of-the-art space suit designed to protect the astronauts from the harsh lunar environment.

How are space suits designed and how have they evolved behind the scenes?

To find out more, we sat down with Ayumu Tokaji, a 'space development evangelist' who also supervised the special exhibition 'Deep Space Exhibition,' currently running at Miraikan (The National Museum of Emerging Science and Innovation) in Tokyo. He gave us the inside scoop on everything from the history of space suits and the latest cutting-edge developments to their potential applications in our everyday lives.

Extravehicular Space Suits: Built to Withstand Extreme Temperatures and High-Speed Dust

First off, what exactly is a space suit?

As the name suggests, it's a suit worn in space. There are two main types: 'extravehicular activity (EVA) suits' for working outside the spacecraft, and 'intravehicular activity (IVA) suits,' which are pressurized suits worn inside the spacecraft.

EVA suits are worn when performing missions outside the spacecraft. They include a backpack with a life support system that supplies oxygen, power, and other necessities.

On the other hand, the intravehicular suit, also known as a 'pressure suit,' is worn during rocket launches and re-entry to Earth. It doesn't have its own life support system; instead, the spacecraft provides life support, and the suit works in conjunction with the vehicle.

So, not all space suits are the same. What specific functions do EVA suits have?

Because space is a vacuum, the temperature fluctuations are far more extreme than on Earth. The temperature difference between a sunlit area and a shaded area can be as much as 200°C.

Furthermore, tiny particles of dust (debris) are flying around in space at incredible speeds of about 8 km per second—fast enough to travel between Tokyo and Osaka in under a minute. Even a collision with a minuscule particle could cause catastrophic damage.

EVA suits are equipped with advanced protective features and temperature control systems to shield astronauts from these harsh conditions.

What kind of materials are used?

The outer layer uses special materials like fiberglass, which can block very small particles of dust. The inner part consists of nearly 14 layers of materials like nylon to provide both insulation and an airtight seal.

With 14 layers of fabric, it must be pretty difficult to move around.

In the weightlessness of space, the thickness and weight of the fabric aren't much of an issue.

The real challenge is the 'pressure' inside the EVA suit. Since humans can't survive in a vacuum, the inside of the suit is filled with air, causing it to inflate like a balloon.

Astronauts have to perform precise tasks, like gripping objects, while fighting against this internal pressure. That's why even short tasks can be extremely exhausting.

Is the process of putting it on also difficult?

The current EVA suits used on the International Space Station (ISS) are two-piece models. The procedure itself is straightforward: you put on undergarments with a built-in cooling system, then the top and bottom parts of the suit, and finally the gloves and helmet.

However, getting suited up is a real challenge. If the suit’s internal pressure was set to 1 atmosphere (the same as on Earth), it would inflate like a balloon due to the pressure difference, making it incredibly difficult to even bend your arms or fingers. For this reason, the internal pressure is set lower than inside the ISS. But jumping into this low-pressure environment without preparation is dangerous—it can cause a condition known as decompression sickness, where nitrogen dissolved in the blood forms bubbles that can clog blood vessels.

To prevent this, astronauts must perform a crucial preparatory procedure called "pre-breathing" before putting on their suits. This involves inhaling pure oxygen to purge nitrogen from their bodies, a process that takes at least 140 minutes each time.

A New Generation of Space Suits, 40 Years in the Making

Could you tell us about the history of space suits? The early ones bring to mind a silver color.

You're thinking of the early pressure suits used during programs like the Mercury project. The technology wasn't fully developed back then, so they were essentially modified versions of fighter pilot pressure suits. That's why they used a silver-colored fabric coated with vapor-deposited aluminum.

Today, the standard for suits used outside the spacecraft is white, as it's better at reflecting sunlight and preventing the suit from overheating.

When were the EVA suits currently in use on the ISS actually made?

Believe it or not, no new EVA suits have been made for the ones kept on the ISS in about 40 years. They've been using the same modular suits all this time, just swapping out parts to fit different astronauts and making repairs as needed.

These suits have an incredibly complex design that required exceptionally precise sewing skills. In fact, it's said that about 40 years ago, NASA commissioned highly skilled artisans from a women’s lingerie manufacturer to hand-sew them.

However, those original manufacturing techniques have since been lost. That’s why, for the upcoming Artemis program, new space suits are being developed from the ground up.

So, what are the key requirements for the Artemis program's EVA suits?

The biggest challenge with the current EVA suits, as I mentioned, is their lack of mobility. This stiffness poses a problem for scientific tasks on the lunar surface, like collecting samples, so a major improvement in flexibility is essential.

Additionally, the Moon’s surface is blanketed with regolith, a fine and razor-sharp dust. Even small amounts can clog a suit’s joints or cooling systems, potentially leading to serious malfunctions. Preventing this is therefore a top priority.

Intravehicular Suits: Staying Clean on Long Missions Without a Washing Machine

What about the intravehicular pressure suits worn during launch and re-entry?

The primary purpose of an intravehicular pressure suit is to keep an astronaut alive in the unlikely event of a spacecraft emergency, providing a lifeline until they can return safely to Earth.

While it can maintain internal pressure, it’s not designed to protect against impacts from space debris. Unlike the bulky EVA suits, these are made of softer materials and lack the large life-support backpack, giving them a much more streamlined look.

Because these intravehicular suits are developed in tandem with their specific spacecraft, recent versions—like the one for SpaceX's Crew Dragon—are packed with the latest technology.

What are some of the most striking advancements in these intravehicular suits?

While there have been plenty of functional upgrades, the biggest shift in recent years has arguably been in their design.

Historically, the number one priority for space suits was, of course, keeping the astronaut alive. Aesthetics were a distant second.

But that all changed in 2020 with the sleek intravehicular suit introduced for SpaceX's Crew Dragon spacecraft. Featuring elements like a 3D-printed helmet and touchscreen-compatible gloves, its sophisticated design was a dramatic departure from anything that came before.

What's more, for the ongoing Artemis program, the luxury fashion brand Prada is collaborating on the design. This partnership aims to create truly "cool" space suits that perfectly blend high-level functionality with stylish aesthetics.

Astronauts aboard the ISS seem to wear casual clothes like T-shirts.

That's right. While on the International Space Station, they can wear everyday clothes, just like on Earth.

However, laundry isn't an option in space. Plus, transporting supplies is incredibly expensive—reportedly costing as much as 1 million yen per kilogram. This makes changing clothes frequently a challenge. For instance, they might end up wearing the same polo shirt for as long as 15 days, or the same pair of underwear for about three days.

Because of this, the everyday clothes astronauts wear are treated with special antibacterial and deodorizing technologies to prevent odor and hygiene issues, even after being worn for extended periods.

Biosuits: The Future Standard for Space Suits

How do you see space suits evolving in the years to come?

In the long term, "Biosuit – Gallery – Home," which utilize special shrinkable fibers, will likely become the mainstream.

These suits can supply one atmosphere of pressure just around the helmet, eliminating the need for "pre-breathing," a mandatory procedure with current space suits. This evolution is crucial for saving time in a future era of space colonization.

They are also easier to put on, even for individuals with less muscle strength, making them the likely standard as space travel becomes accessible to more people.

With Mars colonization being a hot topic, will the space suits designed for Mars be different?

For activities on Mars, the suits will need to be significantly lighter than those used on the Moon or in the vacuum of space.

A current extravehicular activity (EVA) suit weighs around 120 kg. This isn't an issue in microgravity environments like the International Space Station, but it translates to a load of about 20 kg on the Moon and a hefty 40 kg on Mars. It's not practical to move around in a 40 kg outfit, so a radical reduction in weight is essential.

Lately, we've seen apparel brands incorporating technologies from space development. How do you think the evolution of space suits will impact our daily lives in the future?

A space suit is a marvel of cutting-edge technology.

Moving forward, the advanced technologies spurred by the Artemis program will undoubtedly find their way back into our daily lives. For instance, the technology behind in-flight wear that stays clean for long periods could be applied to emergency disaster apparel or outdoor gear.

Space exploration truly holds the potential to enrich our lives here on Earth.