These miniature spacecraft have allowed us to operate in space for over half a century
When the United States and the USSR first decided to venture into the cosmos in the mid-20th Century, it was readily apparent that they would need something to protect their explorers from the harshness of space. While pressure suits had been used before on high-altitude jets, no one was quite sure how the human body would cope with weightlessness, and particularly with the vacuum of space, if a spacewalk was to be attempted.
One thing that was known for certain, however, was that exposure to space without a spacesuit would be fatal. 20 kilometres (12 miles) above the Earth the atmosphere becomes so thin, and the atmospheric pressure is so low, that the water and blood in a human body will boil. Above this point, known as the Armstrong limit, some sort of protection is vital. Therefore a mini spacecraft designed to protect its occupant from the harshness of space, or a spacesuit to you and I, was born.
Spacesuits come in a variety of shapes, sizes and uses. In the modern day on the International Space Station, astronauts wear flight suits for launch and re-entry that are largely designed to protect the occupant in case of a bailout. During a spacewalk, they have a much more sophisticated suit that allows them to operate in space.
While early iterations were bulky and basic, more modern spacesuits make use of computerised technology, cooling systems, movable joints and more to make operations in space more comfortable for astronauts. Future spacesuits, which are now in development, will allow greater dexterity and movement than ever before, letting astronauts operate on the surface of another body such as the Moon, an asteroid or Mars.
While modern astronauts can generally wear what they want on the ISS, in the early days of spaceflight there wasn’t room to get changed into different clothes or spacesuits on a spacecraft. The Soviet Union’s Vostok and Voskhod spacecraft, and the USAs Mercury and Gemini spacecraft, were all small and cramped, designed largely to test various aspects of spaceflight in orbit but not designed for long stays in space. The prospect of switching attire was not something that was tackled for some time; in fact, the first time a spacesuit was taken off during flight was not until December 1965 by astronaut Jim Lovell on the Gemini 7 mission.
The first spacesuit used in space was, of course, the one worn by Yuri Gagarin when he became the first human in space aboard Vostok 1 in April 1961. This was the Russian SK-1 suit, which was basically a glorified pressure suit designed only to protect Gagarin during the flight and if he had to bailout (which, ultimately, he did upon re-entry), and not for a spacewalk. The Russian SK-1 suit was used from 1961 to 1963 with its last wearer being Valentina Tereshkova, the first woman in space, on the Vostok 6 mission, albeit a slightly modified version for a female, known as the SK2.Hot on the heels of the Soviets in both spacecraft and spacesuits, the Americans had their own suit ready for the Mercury programme. This was a derivative of the Navy Mark IV suit that had been used for high-altitude flights. It used a ‘closed loop’ system to provide oxygen to the astronaut, had an aluminium-coated nylon exterior for thermal control, and straps and zippers for a snug fit. The spacesuit could also be pressurised in an emergency in the case of sudden spacecraft depressurization, but this never happened throughout the Mercury programme.
The next spacesuit to arrive was arguably one of the most important ever designed. On the Voskhod
2 mission, the second and final flight of the short Soviet Voskhod programme, it had been decided that Alexey Leonov would attempt humanity’s first spacewalk. The previous flight, Voskhod 1, had consisted of a three-man crew that were cramped into the Voskhod spacecraft. Somewhat dangerously, they flew without spacesuits as there wasn’t space in the craft for all of the cosmonauts to wear one. Leonov, meanwhile, flew with just one other cosmonaut, and so was able to wear the Berkut spacesuit. This revolutionary suit, twice as heavy as the SK-1 suit worn by Gagarin, allowed Leonov to operate outside the spacecraft for 45 minutes, although he ultimately only stayed outside for 12 minutes. When Leonov tried to re-enter Voskhod 2, though, he found the suit had inflated too much and he had to bleed pressure from it to get back in the spacecraft. Following these complications, it was decided to retire the Berkut spacesuit.
Once again, just behind the Soviets were the Americans with their Gemini spacesuit. Like the Berkut suit, this was designed to allow astronauts to operate in the vacuum of space, or at least one iteration of it was. Four different Gemini suits were designed: the G2C as a prototype suit, the G3C and G5C for launch and re-entry, and the G4C forspacewalking. Astronaut Ed White wore the G4C spacesuit when he completed the first American spacewalk in June 1965. Using layers of nylon, removable boots and a full-pressure helmet, the Gemini suits were a vital stepping-stone to the Apollo suits that would be used to walk on the Moon.
Both the Americans and Soviets, however, found those early spacewalks very difficult. They required huge amounts of exertion and astronauts and cosmonauts would often get back into their spacecraft approaching exhaustion, their suits full of sweat. As they were unable to get out of their spacesuit in their spacecraft, most of these early spacewalkers had to sit and wait until they returned to Earth to remove the uncomfortable apparel. It was actually Buzz Aldrin (turn to page 70 for our exclusive interview) who solved the conundrum of spacewalks on the Gemini 12 mission in November
1966. He suggested training astronauts underwater for the rigours of space, and also consulted on the addition of handrails and footholds to the exterior of spacecraft to give spacewalkers something to hold on to in space, reducing the exertion they needed to perform even simple tasks. Without the important Gemini 12 mission, where Aldrin demonstrated effective operations in space, humans might not have been able to walk on the Moon.
Before Buzz Aldrin and Neil Armstrong walked on the lunar surface, however, the Soviets were developing their own spacesuit to be used on the Moon. First, they aimed to perfect the art of spacewalking with Yastreb. This spacesuit, with input on its design from Leonov, was a clear upgrade over the previous Berkut suit; it used pulleys and lines to assist with movement, and was generally much more manoeuvrable. It was used only on a crew exchange between Soyuz 4 and 5 in 1969, with the other Soyuz missions not using pressure suits. Yastreb’s successor was Krechet-94, another revolutionary Soviet suit intended for lunar spacewalks. Its major innovations were a rear-entry hatch, known as a suitport, and a semi-rigid design. Both of these concepts have been incorporated into modern spacesuits.
NASA, meanwhile, had been hard at work on its own lunar suit. The Apollo A7L spacesuit was a huge step-up from the Mercury and Gemini spacesuits, providing additional levels of comfort, protection and manoeuvrability that were unmatched before. Designed by ILC Dover (see ‘The story of the A7L’ boxout on page 21), its primary purpose was ultimately to allow astronauts to operate effectively on the surface of the Moon. With 12 successful moonwalkers donning the suit, it was a resounding success. An A7L was tailor-made to each astronaut, but every Apollo mission actually required 15 suits, even though there was only a primary crew of three. This is because, of the primary crew, each astronaut had three suits: one for flight, one for training and one for backup. The remaining six suits for each mission came from the backup crew; each of them needed two suits, one for flight and one for training. For Apollo 11 through 17, therefore, 105 suits were made. An upgraded version of the spacesuit was also used for all three manned missions to the Skylab space station.
With their cancelled lunar programme behind them, the Soviets set about designing two new spacesuits, one for launch and re-entry and the other for spacewalking. Both these spacesuits would be so successful that they would become the cornerstone of the Soviet Union’s, and later Russia’s, space exploration. The Sokol spacesuit was a lightweight pressure suit that astronauts wore, and still wear, on the Soyuz spacecraft during launch and re-entry. These suits were the direct result of a tragedy when the three-man crew of Soyuz 11 were killed on 30 June 1971 as a result of their spacecraft depressurising on re-entry. They were unable to wear pressure suits as the spacecraft was too small, and therefore they were killed instantly. A redesign of the
Soyuz spacecraft followed, with the number of crew reduced from three to two to allow them to wear suits during launch and re-entry. It would not be until 1980 that three people would travel in a Soyuz again, when the spacecraft was big enough to support three astronauts in pressure suits.
The Soviets’ other suit was the Orlan, a versatile spacewalking suit that, although it has been upgraded over the years, is still in use today. In fact, the Chinese used it as the basis for the design of their Feitian suits that they use for their current spaceflights. It has a rear-entry port, allowing people to don it in minutes, and is semi-rigid (with a solid torso and flexible arms). It’s used in the modern era for spacewalks on the ISS, having previously been used both on the Salyut and Mir space stations. The only other spacesuit designed by the Russians was the Strizh suit, which was developed to be used on the Russian Buran space shuttle. Like their earlier lunar programme this was scrapped, although the suit was lucky enough to have one flight on a mannequin during an unmanned test flight of the shuttle in 1988.
The Americans also settled on a preferred series of spacesuits. In the early-Eighties, the Extravehicular Mobility Unit (EMU) was introduced, originally to be used on spacewalks outside the Space Shuttle and is now used on the ISS. In tandem with this was the Shuttle Ejection Escape Suit that, as you might have guessed, was used on the Space Shuttle as a launch and re-entry suit. It was scrapped after the fourth Space Shuttle missions in favour of regular flight suits, while the Challenger disaster in January 1986 prompted the design of the iconic orange Launch Entry Suit (LES), and later the Advanced Crew Escape Suit (ACES), which were used for the remaining Space Shuttle missions until it was retired in July 2011.
Despite the relative advances in spacesuit technology, though, operating in space is still no easy feat. It’s slow going, and even installing a simple component on the exterior of the International Space Station can take several hours. To assist astronauts and cosmonauts, the gloves of a spacesuit often have rubberised fingertips that help with grip, while loops allow tools to be tethered to the gloves. Tools can also be stored on the torso of the spacesuit, while a number of dials and switches on the front of the suit allow astronauts to regulate their temperature, pressure and more.
These complex machines have been vital in allowing astronauts to operate effectively and safely in space for over 50 years. While early space missions involved limited stays of just minutes in space, modern-day astronauts rely on their spacesuits for hours at a time as they work on the exterior of the International Space Station, and without spacesuits, extravehicular activities (EVAs), or spacewalks, would simply not be possible. And of course, without the complex suits designed for the Apollo missions, astronauts would also not have been able to walk on the Moon. Spacesuits have allowed us to study and explore space like never before, and their continued evolution and development will allow us to ultimately set foot elsewhere in the Solar System in decades to come.