Beyond Earth’s Atmosphere: The Extraordinary Technology of the Spacesuit Keeping Astronauts Alive

Team Udayavani, Aug 19, 2024, 8:29 PM IST

NASA is facing a tough problem bringing astronauts Sunita Williams and Butch Wilmore, stuck in space for more than two months, back to Earth. They may have to return without wearing proper spacesuits because the suits made by Boeing do not work with the SpaceX spacecraft they are supposed to use. This mix-up is a big issue as NASA needs SpaceX’s help to bring the astronauts home safely. NASA said that the suits from Boeing and SpaceX cannot be switched between the two spacecraft, making it a tricky situation.

NASA is now looking at other options due to this new information. One idea is to send the right spacesuits to the International Space Station (ISS) before astronauts Williams and Wilmore come back, expectedly around February 2025. However, there is still the worry that, if something urgent happens, they may have to return without proper suits.

Astronauts wear specialized suits tailored for distinct scenarios: spacecraft suits, ISS attire and spacewalk or extra-vehicular mobility unit (EMU) suits. Each suit serves a unique purpose based on the specific conditions of the environment the astronauts are operating in. Let us explore a detailed examination of these specialized astronaut suits, each meticulously designed for spacecraft missions, ISS operations and extra-vehicular activities, ensuring optimal functionality in diverse environments.

In space, where there is no air and very low gravity, humans cannot survive without special equipment. If a spacecraft loses pressure or during spacewalks outside the ISS, astronauts need protection. That is where spacesuits come in. These suits are designed to keep astronauts safe and comfortable, allowing them to perform their tasks in the harsh conditions of space. Let us explore how these suits work and what makes them essential for space missions.

Special suits for astronauts travelling to, and from, space

During launch and re-entry, astronauts wear a partially pressurized suit with a parachute pack. This suit includes a helmet, gloves and boots for protection. Inside the suit are air bladders that inflate if the cabin pressure drops. At low pressure, blood can pool in the lower body, causing fainting. These bladders help maintain pressure to prevent blackouts.

From LES to ACES to Advanced Crew Dragon Suits

After the Space Shuttle Challenger disaster in 1986, NASA realized the importance of having a way for astronauts to evacuate in an emergency. They created special orange suits, also known as pressure suits, for astronauts to wear during launch and when coming back to Earth.

The first version of the orange suit, known as the Launch Entry Suit (LES), was first used on the STS-26 in 1988. NASA then created the Advanced Crew Escape Suit (ACES), which was lighter, less bulky and easier to wear than the LES. This new suit was designed to help reduce stress and fatigue for astronauts and was first worn on the STS-68 in 1994.

When getting on the Soyuz spacecraft, crew members wear Russian Sokol spacesuits.

The most recent pressure suits were worn during the launch of the commercial spacecraft, Crew Dragon, in 2020. These suits include a helmet made with 3D-printing and gloves that can be used with touch screens, making them much more advanced than older pressure suits.

Ensuring astronaut safety in extreme conditions

Through the use of high-tech suits worn during spacewalks, when astronauts step outside their spacecraft while in space, or EVA, which stands for Extra-Vehicular Activity. Nowadays, astronauts perform spacewalks outside the International Space Station (ISS). These spacewalks can last anywhere from five to eight hours, depending upon the task at hand.

Russian astronaut Anatoly Solovyev holds the world record for the most spacewalks, having completed 16 of them. Altogether, he has spent over 82 hours outside in space. That adds up to nearly three and a half days in total! Following him is NASA’s Michael Lopez-Alegria, who has spent 67 hours and 40 minutes in space during 10 EVAs or spacewalks.

Why do Astronauts go on Spacewalks?

Astronauts go on spacewalks for a variety of reasons. Spacewalks allow them to work outside their spacecraft while still in space. During a spacewalk, astronauts can conduct science experiments by placing them on the outside of the spacecraft, helping scientists understand how space conditions affect different materials.

Spacewalks also give astronauts the opportunity to test new equipment and repair satellites or spacecraft while they are still in space. This means they can fix things on the spot instead of having to bring them back to Earth for repairs.

How Do Astronauts Go on Spacewalks?

When astronauts go on spacewalks, they wear spacesuits to stay safe. These suits provide them with the oxygen they need to breathe and the water they need to drink. Astronauts put on their spacesuits several hours before starting a spacewalk. The suits are pressurized, meaning they are filled with oxygen to keep the astronauts safe in space.

After putting on their suits, astronauts breathe pure oxygen for a few hours. This process removes all the nitrogen from their bodies. If the nitrogen is not removed, gas bubbles can form in their bodies during the spacewalk, causing pain in their shoulders, elbows, wrists and knees. This condition is known as “the bends” because it affects the joints where the body bends. Scuba divers can also experience “the bends”.

Astronauts are now prepared to exit their spacecraft or the ISS. They leave through a special door called an airlock, which has two doors. When inside the spacecraft, the airlock is sealed to keep the air from escaping. To start a spacewalk, astronauts enter the airlock, close the first door securely and then open the second door without letting any air escape from the spacecraft. After finishing their spacewalk, they return through the airlock.

Are Astronauts Safe During Spacewalks?

When astronauts go on a spacewalk, they use safety tethers to stay connected to their spacecraft, or the International Space Station (ISS). These tethers work like ropes, with one end attached to the astronaut and the other end secured to the spacecraft, or ISS. This ensures that astronauts do not drift off into space. They also use tethers to keep their tools from floating away by attaching them to their spacesuits.

Another safety measure is a device called SAFER, which stands for Simplified Aid for EVA Rescue. SAFER is worn like a backpack and has small jets that allow astronauts to move around in space. If an astronaut accidentally becomes un-tethered, SAFER helps them return to the spacecraft. They control SAFER using a small joystick, similar to what you would find on a video-game controller.

How Do Astronauts Train for Spacewalks?

Astronauts prepare for spacewalks by practising in water, which simulates the feeling of floating in space. They train in a huge swimming pool called the Neutral Buoyancy Laboratory (NBL), located near NASA’s Johnson Space Center in Houston, Texas. This pool contains 6.2 million gallons of water (about 23.5 million litres). For every hour that astronauts plan to spend on a spacewalk, they practise for seven hours in the pool.

Astronauts also prepare for spacewalks using virtual reality, which is similar to playing a video game. They put on a helmet with a video screen inside, along with special gloves. The screen displays a video of what they will see during a spacewalk. As the astronaut moves, the gloves help translate those movements into the virtual environment. This virtual reality simulation closely mimics the experience of a real spacewalk.

Spacesuits Worn during EVA or Space Walks

Spacesuits are essential for astronauts because they provide protection and support in space. They help regulate body temperature, keeping astronauts from getting too hot or cold. The suits supply oxygen for breathing and have water for drinking. They also shield astronauts from space dust, which can be dangerous since it moves faster than a bullet. Additionally, the suits have gold-lined visors to protect their eyes from the bright sunlight.

Gold-lined visors—a shield to protect the eyes from harmful light and radiation—are used in spacesuits because gold helps block harmful solar radiation. It effectively reflects intense sunlight, protecting the astronauts’ eyes from the bright light and ultraviolet rays in space.

What Exactly are components of a spacesuit?

A spacesuit has several parts:

• A section covers the astronaut’s chest
• Another part covers the arms and connects to gloves
• The helmet protects the head
• The lower part covers the legs and feet

Some parts have multiple layers, each with a different function:

• Some layers keep oxygen inside
• Others protect from space dust

Astronauts wear a special garment under their spacesuits. This outfit covers most of their body except the head, hands and feet. It has tubes woven into it where water circulates to help keep them cool.

The spacesuit has a backpack that provides oxygen for astronauts to breathe and removes the carbon dioxide they exhale. It also powers the suit with electricity. A fan circulates the oxygen and a water tank keeps the cooling system running. Attached to the back of the suit is a device called SAFER. It has small thruster jets. If an astronaut drifts away from the space station, they can use SAFER to fly back.

Astronauts wear ‘space suits’, which is also known as Extravehicular Mobility Units (EMUs), for spacewalks outside their spacecraft. A spacesuit costs around $12 million. This is actually cost-effective because each suit is not made for just one astronaut and can be reused for many years if it stays in good condition.

How does clothing balance style and function?

Inside the ISS, the air pressure is the same as on Earth (1 atm) and the temperature and humidity are kept comfortable. So, except for special pressure suits used during launch and landing, astronauts can wear regular clothes just as on Earth.

Since there is no way to do laundry in space, astronauts pack a set number of clothes for their trip—like one polo shirt for every 15 days and a fresh pair of underwear every three days. Sometimes, the crew also wears matching shirts with the mission’s name. NASA provides these clothes, but Japanese astronauts might bring clothes from JAXA, included in NASA’s supplies.

What happens to clothes once finished wearing?

Astronauts cannot wash clothes in space, so when they are done with them. The clothes are packed with other trash into a cargo vehicle that delivered supplies to the ISS. This waste burns up as the vehicle re-enters Earth’s atmosphere.

By Girish Linganna

(The author of this article is a Defence, Aerospace & Political Analyst based in Bengaluru. He is also Director of ADD Engineering Components, India, Pvt. Ltd, a subsidiary of ADD Engineering GmbH, Germany. You can reach him at: [email protected])

Disclaimer: The views expressed above are the author’s own and do not reflect those of Udayavani