Ever fancied yourself in a spacesuit? Whether in fact you believe that a spacesuit makes desirable fancy dress, it is undoubtedly, more so than any other profession in which a high-profile uniform is worn, iconic. However compared to those occupations in which uniforms are primarily worn to draw attention, spacesuits represent far more. So exactly to what extent are spacesuits the product of fashion or function? Let’s take a look at a few designs to find out…
Just as the colour and style of a police officer’s uniform may vary depending on their nationality or current circumstances, so the same can be said of the different spacesuits that men and women have worn to head into space.
Silver in appearance, the Mercury Program ‘spacesuit’ was a partial-pressure suit that could temporarily countermeasure any unintentional drop in atmospheric pressure within the spacecraft at high altitude. It was however known for being difficult to bend at limb joints when pressurised. Besides the suit’s reflective aluminized outer nylon skin possibly being considered an aesthetic improvement from its olive green Navy aircraft flight suit cousin, it was thought at the time that it would offer an added degree of protection from radiation, the deep cold of space, and the heat build-up on re-entry to whatever extent this could be felt from inside the spacecraft. Slung-shot far above the 100km mark, Alan Shepard, the first American astronaut to enter space wore the Mercury Program spacesuit in May 1961.
Decades later we see Space Shuttle and International Space Station crews kitted up in blue. Primarily designed for safety and comfort on-board ship, cobalt blue flight suits have pleats to allow room for the height extension of 2-5cm most human bodies undergo when moving into a microgravity environment. Closely fitting to avoid the fabric catching on switches and causing accidents, the soft cotton zip jacket and trousers are treated to be fire retardant. Designed to suit the practical nature of the work on-board, these smart-looking yet comfortable overalls also have multiple pockets built into the suits. Many of the garment pockets are zipped and any open pockets have velcro to prevent the velcroed sunglasses, notebooks, small tools etc. from floating out while the astronauts are moving in any possible direction on board.
When astronauts arrive at the NASA training centre they also collect: a navy short-sleeved cotton-knit shirt, sleep shorts, slippers, socks, underwear. Providing no additional protection, the blue astronaut outfits differ from their orange, silver, and white counterparts in that they are completely unpressurised and therefore can only be worn within the controlled environment of the spacecraft/ISS. So where do the orange spacesuits fit in? There have been a number of iterations of this brightly coloured spacesuit in the story of the Space Age. The very first uniform that could officially take the title ‘spacesuit’ preceded even the USA’s Mercury Program. Bright orange in colour this partially-pressurised flight suit was worn by cosmonaut Yuri Gagarin, in April 1961.
Dyed in ‘International Orange’, these ‘launch and entry suits’ (LESs) were worn until 1998 by astronauts commencing or concluding a Space Shuttle mission. Designed to be spotted against any landscape, the high-visibility outfit guaranteed the crew’s safety on the launch-pad and ensured their being found in the shortest period of time, should some unforeseen flight incident have required a search and rescue team be deployed to the desert, jungle, or sea to locate them.
Although unable to protect them from the full harshness of space, these partially-pressurised suits would prolong the astronauts’ survival should their spacecraft be leaking air and they at the time happen to be within Earth’s atmosphere. Also known as ‘emergency pressure suits’ during Shuttle missions built-in ‘bladders’ would fill with air on detecting reduced cabin pressure. By applying pressure to the lower body the bladders help prevent blood leaving the brain, pooling in the lower body, and the crew member from blacking out.
As of 1994 a still more advanced suit came into service for the remaining Shuttle missions. Produced by the David Clark Company of Worcester, Massachusetts, the ACES (Advanced Crew Escape Suit) was designed to further improve the mission crew’s chances of survival in the event of a mid-flight incident. Fully-pressurised, with another layer of insulation, improved ventilation, and including a survival backpack, a very similar white version of the spacesuit called Sokol, is worn by astronauts and cosmonauts travelling to and from the ISS today.
Best known of all spacesuits are of course the white. Made famous by numerous spacewalks and the Apollo Moon landings, the bulkiest of all the astronauts’ uniforms adopt a puffy appearance as they are fully-pressurised with 100% oxygen to protect their occupants’ bodily fluids boiling into gas in the hard vacuum of space. The mission crew sent into space had three spacesuits each, the training suit, the actual mission suit, and the backup mission suit. The backup crew had the same wardrobe, minus the backup suit. During the Apollo program the spacesuits were tailor-made to accommodate the physiques of the flight commander, command module pilot, and lunar module pilot respectively.
Officially called EMU’s (Extra-Vehicular Mobility Units) and manufactured to the lightest achievable weight on Earth of 127kg (20 stone) before anyone climbs inside, the two-part suits donned by astronauts intending to perform any kind of EVA (extra-vehicular activity) outside of the Skylab, Shuttle, or ISS are entered and connected at the waist. Composed of up to 14 layers of materials, all of which selected for their resistance to fungal or bacterial growth, EMUs are famous for their tough shells and have a life expectancy of 8 years. The International Latex Corporation (now ILC Dover, Inc.), the same manufacturer contracted to make the cushioning lander airbags for the Sojourner, Spirit and Opportunity Mars exploration rovers was responsible for their production. At every stage of the process the well-being and comfort of the astronauts was given top priority.
A composite of materials throughout the suit had to, on the side of the astronaut facing away from the Sun, insulate his/her body from temperatures as low as -129 degrees C (touch temperature), while alternately protecting his or her other side from raw solar radiation and temperatures of up to 120 degrees C. Not only were these engineering challenges met within the confines of a one-man spacesuit, but to reduce the chances of metabolic overheating underneath the many layers of insulation while performing an EVA, a warm and cold water circulation system with an intricate layer of tubing was to be worn just above the astronaut’s skin. Supported by the tight-fitting spandex full-pressure suit, it was altogether known as the Liquid Cooling and Ventilation Garment. Over the top of the polyurethane-coated nylon and the polyester structural restraint layer, is a woven Kevlar, Teflon, and Dacron anti-abrasion layer. Also called the Thermal Micrometeoroid Garment this final barrier to space shields the crew-member, their suit integrity, and essential spacesuit survival systems from space debris that could be moving at up to 8000m/s.
Subsequent Space Shuttle Missions in contrast benefited from the availability of multiple suit components in a wide range of sizes which could be mixed and matched, then locked together section by section until a perfect kit-up was achieved for each astronaut prior to the mission. So why the spacesuit’s neutral colour? Well you’ve probably guessed the two-part answer. Firstly as the design antithesis of camouflage uniforms, these white suits are considered to be the easiest ‘colour’ to spot in the astronauts’ work environment, against the black backdrop of space. The other health and safety reason behind the suit’s monotone colour scheme is that as the poorest absorber but greatest reflector of the Sun’s invisible infra-red radiation, the potential for an astronaut to gradually overheat as he/she works in direct sunlight for anything up to nine hours during an EVA, is reduced to a minimum. The greatest deviation from the EMU’s uniformly stark colour scheme, has remained the red astronaut identification stripes marked in four places on one of the two spacesuits crewmembers are sent out in to perform a spacewalk or EVA.
So finally to return to our opening question, spacesuits, fashion or function? A: EMU’s, the aesthetically unique white spacesuits worn by astronauts in the dark void of space are much more than costly attention-grabbing occupational fashion symbols, or even purely functional work uniforms, they are in effect the smallest life-sustaining one-man spaceships in existence.
(Article by Nick Parke, Education Support Officer)