How did space suits evolve over the course of the Space Shuttle program, and what has been going on since? And why are spacesuits being blamed for a delay in the Artemis Program?
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Welcome to tex Stuff, a production from I Heart Radio. Hey there, and welcome to tex Stuff. I'm your host job than Strickland. I'm an executive producer with iHeart Radio and I love all Things sech And we are continuing our series about space suits and their evolution. So the last episode we really focused on the suits used in the Apollo missions. We also talked a lot about pooping in space, which I felt was necessary to talk about. It's also necessary to do sometimes, and those Apollo space which actually did change a bit over time. I'll talk a little bit about that in this episode, because the suits that were used in the final missions were a little different from the earlier ones, but overall they were mostly kept to the same design once you got to the block to Apollo missions after the canceled Block one design. And now we're going to talk a bit about the p l s S, which, depending upon what source you're reading, either stands for portable life support system or primary life support system, but in the case of Apollo, it really means the backpack. This is the life support system that attached to the suit and allowed astronauts like Neil Armstrong to you know, gallivan around on the Moon without being connected by a life support umbilical tether to you know, like the lunar module. The p l S S would provide the pressurization needed inside the suit as well as the oxygen that the astronauts breathe. The ability to scrub c O two from the suit also very important, and it also acted as a cooling system to help with temperature control with the water cooling. So in addition, astronauts on the Moon also had an Oxygen Purge System or OPS, which stood in as an emergency backup should the p l s S fail. So while it's as oxygen purge system and it makes it sound like you're getting rid of all your oxygen, it was a secondary oxygen source, but it only gave the astronauts really enough time to be able to return to the lunar module and then connect their suits back to the module's life support system if things really went you know, pear shaped. The p L S S started off in development in nineteen six one, nearly a decade before one would be used on the Moon, and that was necessary because we were learning so much about what would be needed in order to make a Moon mission successful. So while development was begun back then, a lot of the stuff we learned would mean we'd have to change designs. For one thing, engineers learned that the metabolic requirements to get stuff done in space were really way higher than what was initially estimated, which meant astronauts were having to put forth a lot more effort than was originally guessed, and that meant that the life support says STEMS would need to keep up with that in order to supply the necessary oxygen and keep the astronauts body temperature at an acceptable level. But how do you cool off the water circulating through the suit. If you remember, a an inner layer of the suit had plastic tubes essentially through which water would run and carry body heat away. Well, you've got to get rid of that heat, right, you have to have some sort of heat exchange in order for the water to cool down again. Otherwise eventually you're just going to be running body temperature level water or hotter through the suit, and that doesn't help you with maintaining a right temperature. Well, in this case, the answer ended up being a plate that to the naked eye seemed like it was a solid plate, but in fact it had microscopic pours in that plate, so warm water from the cooling system would fill up those pores just a little bit, not a whole lot of water, and then it would just boil off into space. And because boiling is an endothermic reaction, it actually carried heat away from the system, and that would cool the water that remained, uh, and some of that water would just freeze in those pores, effectively sealing the pores. But then this water would get warmed by the cooling system or the gas circulating system, and the process would repeat itself, and it would continuously cool as long as you had enough water running in the system, and you weren't losing a ton of it, you know, all at once or anything. It was little bits, so it could run for a while before being depleted. The invention would end up being used in many future space technologies, including the International Space Station, so not just for space suits. Now, I mentioned that the p LSS had an oxygen supply, which is obviously a necessary component for a life support system for a human being, and this was pure oxygen as opposed to the mix of gases that we breathe here on Earth. A typical lungfull down here on the planet is nitrogen twenty one oxygen and then everything else like argonne, carbon dioxide, and some trace elements. All of that is less than a percentage point each. However, in a low pressure environment, going with this kind of mixture could lead to a dangerous situation in which you don't have enough of a concentration of O two in the astronauts lungs and their blood. So most space life support systems actually rely on a supply of pure oxygen instead. Oh an interesting fact, the Space Shuttle and the International Space Station have or you know, in the case of the Space Shuttle had internal atmospheres that mirrored Earth's atmospheres, and for that reason, astronauts dawning spacesuits for a n e v A first had to engage in a bit of pre breathe the activity, which is somewhat confusing, right, I mean, it's a weird thing to say, but what it means is that they had to strap on a mask and breathe pure oxygen for like a period of like four hours in some cases before getting into the space suit and relying on the spacesuits life support system. And the whole reason for doing that was to have a gradual process to remove nitrogen from the astronauts blood, which in turn would reduce the chance that the astronaut would get the bends once heading into the low pressure environment of outer space, just like you would see with someone who is you know, deep sea diving. All right, tangent over, let's get back to the p l s S. Well, it turns out that we humans, you know, we breathe an oxygen and we breathe out carbon dioxide among some other stuff. It's not just pure CEO two. And if we have a significant build up of c O two in our environment, and by significant I mean if CEO two levels rise up to be about eight percent of what we're breathing, well we can't breathe proper. Really it actually it becomes toxic, and obviously that's a problem, potentially a deadly one. So there had to be a way to remove c O two from the suit. So you can think of it as there being one port into which pure oxygen flows in, and there's another port where c O two, mix of c O two and other stuff could exit the suit. And then you would have a scrubbing system consisting of tanks holding a substance called lithium hydrox side and that would do the job of scrubbing CEO two. You see, c O two and lithium hydrox side have a chemical reaction together that produces water and lithium carbonate, and it's pretty darn good at it. You don't need a whole lot of uh this, you know, lithium hydroxide to do the job to remove a good amount of c O two from space. So that's good from a space saving and a weight saving standpoint. So a lot of space suits and spacecraft use canisters of lithium hydroxide in or to remove CEO two from the environment, and then the water from that process can be used in other functions, either like drinking water or an oxygen generator or even you know, the water cooling system and the p l s s would also connect through the suit using multiple connectors so that everything could work in harmony with each other. So obviously like the suit had connectors that docked with the p LSS to allow the functions to go through. For example, in order to have an effective cooling system, you had to connect the water lines in the LCG suit, which remember is underneath all these other layers with the p l S S, and that meant that you had to have these these special things built in so that you had these connections without obviously making any weakness points in the suit. So NASA developed special connectors that would allow this to happen without causing a breach in the system. Pretty ingenious really, to have everything hook up like this. The suit and p L S S continued to evolve over the course of the Apollomys, with later missions taking advantage of lessons learned from the earlier ones, and sometimes those plans had to change in the process. So, for example, while the world marveled at the successful moon landing of Apollo eleven, NASA was already planning ahead to create systems that would allow for longer operation on the Moon, which obviously necessitated more consideration for life support, and to that end, they planned to make p L S S units that could provide life support functions for longer durations. However, budget constraints meant that some of those plans got cut that couldn't afford to do all of them. What was to be a larger secondary life support system got scrapped because there just wasn't money in the budget to have that so what takes its place. Well, it was what was called a buddy life support system or b l s S, and I bet you can figure out immediately what that means. It would allow for someone who had a working life support system to connect their suit directly to a second astronaut who perhaps had a depleted or malfunctioning p LSS, and then the two astronauts could then make their way back to the spacecraft, where they would hook into the spacecraft's life support system. It kind of makes me think of drills in which two scuba divers would share the same scuba tank between them in the event of one scuba divers tank running out of oxygen or otherwise malfunctioning. While astronauts on Apollo missions fourteen through seventeen had the system available, fortunately there was never a need to actually use it. So the buddy system existed, but no one ever had to take advantage of it. It was kind of they're just in case now. The last Apollo mission of the actual Apollo program had the designation Apollo seventeen and was in December of nineteen two. Following that, NASA focused on the first American laboratory in orbit around Earth, which had the name sky Lab, and in order to get stuff, you know, to and from sky Lab, they relied upon unused Apollo capsules And I'll have to do a full episode about sky Lab in the future. But the suits that astronauts wore while aboard sky Lab were very similar to the ones that were using the final three Apollo missions, called the A seven lb pressure suit. The one that Neil Armstrong wore back in Apollo eleven was the A seven L, so that one did not have the B attached to it, and the Skylab version had an extra thermal garment as part of the suit. The lunar landing versions of the A seven lb allowed for greater mobility and were designed so that astronauts could conduct more extensive missions on the Moon's surface, including using the lunar rover vehicle, So the suit had to have greater flexibility than the older A seven L suits, including additional joints built into the suits to allow astronauts to actually, you know, sit on a rover and putter around on the Moon's surface. It actually kind of makes me think of action figures, like there were different types like g I Joe action figures had joints at the elbow and knee, so you could bend the arms and bend the legs. As opposed to action figures from like the original Star Wars action figures, they had no joints at the elbows or knees, so they had very stiff armed and stiff legged movements. Kind of similar to that. These joints were made out of molded rubber, kind of like a like a bellows almost, and you could find them at the shoulders, the elbows, the hips, and the knees. The p l s s could supply up to seven hours of life support towards the end of the Apollo program, allowing for pretty extensive e v A s. The versions worn inside the spacecraft and the type Warren and sky Lab were not quite as fancy as the lunar versions. NASA chose to go with a design for sky Lab that would require astronaut to actually be tethered to the Skylab facility for life support functions during any sort of e v A, so you had that umbilical back to the spacecraft if you were doing an e v A at sky Lab instead of carrying you know, your own portable life support unit. This necessitated a redesign of the front of the suit in order to accommodate the umbilical tether in a way that wouldn't get in the in the way of the astronaut. Right, so you think about it, if you have a hose connected to your chest, you wanted to be in a spot where it's not going to get in the way of your arms if you have to do intricate work on say a spacecraft. Um, so, yeah, this was a bit of a redesign, and the astronauts would connect the other end of the tether to a life support panel inside the airlock of Skylab before depressurization. And while you could have more than one astronaut go on an e v A at once at sky Lab, typically they would each connect to their own panel as opposed to sharing a panel. The panel had multiple out puts, so you could connect more than one tether to a panel, but generally speaking, that's not how the astronauts operated. The astronauts did have a half hour supply of pure oxygen on their suit, just as an emergency backup if for some reason the life support connection to the spacecraft had failed. The suits had a few other differences from the Apollo versions. For one, they had more zippers to allow for easier dawning and daffing of the suits and zero g uh. That did come at the cost of some mobility, but since the Skylab astronauts wouldn't be going on joy rides on the lunar rover, it didn't matter as much to NASA that they wouldn't be able to, you know, like bend at the waist. They also had fewer layers of thermal protection than the Apollo suits. They were using slightly different materials in a new arrangement that still provided thermal protection, so it's not like they got rid of it, they just found a more efficient way of doing it without needing as many layers of material. There were only three crew as in a cruise people going on them. Skyline missions are only three they had astronauts actually go to sky Lab, with the first one in May nineteen seventy three. The last one happened in November nineteen seventy three to February nineteen seventy four. Nine astronauts would visit the sky Lab Across all three of these missions, divided up between the three. That is, so three astronauts per mission Across these three missions, astronauts spent a total of a hundred seventy one days aboard sky Lab. The longest of the three missions was for eighty four days. The cruise traveled to and from Skylab. As I said, with repurposed Apollo command modules on repurposed launch vehicles that you know, we're meant for the Apollo program. But the Apollo program ended and they still had these, so they're like, well, let's use them, um, and so the Apollo capsule, the command capsule would dock at one end of the sky Lab. Clearly, they didn't have the lunar module, there was no need for that, so that part was not attached to the spacecraft. Interestingly, the living quarters of sky Lab were palatial compared to the Apollo capsule. Astronauts actually, we're using a converted fuel tank of a Saturn S for b rocket stage to act as their living quarters, which meant that they had an internal space of twelve thousand, seven hundred fifty cubic feet or three hundred sixty one cubic meters of space. The Apollo capsule was just two hundred eighteen cubic feet or six point one seven cubic meters, so an enormous difference. I imagine that when it came time to, you know, use the bathroom, it was a lot easier to get some space between you and the other astronauts. After that, the Soviets were the only people sending crews up into space using the Soyuz capsule. In nine, the Soviet Union and America conducted some joint missions, with the Soviets in a Soyuz capsule and the Americans were in the final Apollo capsule and the two spacecraft docked with each other in orbit. The two crews worked together on several experiments before the spacecraft separated and they both returned to Earth safely. So this was the Apollo Soyu's mission, not officially part of the Apollo program, but using the final Apollo capsule, and then the United States kind of hit a dry spell. The Soviets continued to launch Soyu's capsules into space, working on small Soviet space stations under the name Salute, but for the USA the crude missions would be on hold until the Space Shuttle was ready to launch, which had a few delays. It was finally ready in ninety one. NASA had hoped to use the Shuttle to help boost sky Lab into a higher orbit and keep Skylab going. But because of the delays in the Space Shuttle program, that opportunity went away. Uh sky Labs orbit deteriorated, and then it broke apart upon re entering the air's atmosphere in nine so there was no way of prolonging that mission. But now we're getting into the next era of space suits, the Space Shuttle era. When we come back, we'll talk about how those suits worked and what was different from the Apollo era suits. But first let's take this quick break. The Space Shuttle era does not have a single suit that we can point to and say this is what Space Shuttle suits were like. There are actually a few different ones, and of course there's a difference between the suits that were worn inside the Space Shuttle for normal operations as opposed for the stuff like take off and landing, and then the stuff worn for e v A S or extra vehicular activities you know, going out into space. But let's start at the beginning. The first mission, STS one, which launched on April twel had two astronauts wearing suits that were based largely on an Air Force flight suit designated S ten thirty. These were worn by pilots aboard the s R seventy one Blackbird aircraft. That's a long range, high speed, and high altitude reconnaissance vehicle. I've actually talked about the Blackbird in other episodes of tech Stuff. The David Clark Company, long associated with flight and space suits, made the variation for the early Space Shuttle cruise, and this one became known as the S ten thirty A, also known as the Shuttle Ejection Escape Suit. Now, as that name suggests, the suit was intended to protect astronauts in the event of an emergency ejection, and they were rated to protect an astronaut up to an altitude of eighty thousand feet and the speed of mock two point seven, which is a big yalza. So let's talk about that for a second to get our minds wrapped around what this means. So, as you climb in the atmosphere, the air pressure drops, which makes sense, right after all, on the ground, you've got the pressure of all that atmosphere pressing down on you. But as you go higher, you have less atmosphere above you, and so there's less pressure pushing down on you. At eighty thousand feet, the air pressure is point four zero six pounds per square inch. Temperature is a bit fiddly when it comes to altitudes. The temperature drops off as you climb up to a point, but then as you hit the stratosphere, the temperature actually starts to go up as you climb, and then as you get beyond the stratosphere, the temperature plunges again no joke, But at any thousand feet you're looking at temperatures of nearly negative sixty two Fahrenheits, So the suit has to protect against both the low pressure and the low temperature. Now let's talk about mock two point seven. Some folks reduce mock to mean a multiple of the speed of sound, so if you're going mock three, you're going three times the speed of sound, which is only part of the picture, because the actual explanation of mock is more complicated. And part of that is because the nature of the speed of sound is more complicated because sound travels at a speed that's dependent upon the medium through which it travels. So, in other words, sound travels at different speeds at different conditions, and those conditions can include things like temperature, so it will travel at different speed at sea level at standard temperature than it will at eight feet. So mock actually describes the ratio of the flow velocity of some fluid like air compared to the speed of sound through that particular medium. For shorthand, you could say it's like a multiplier. You know, you could say, oh, it's multiplied by the speed of sound. But just know that when you really dig down, it gets a little more complicated than that. Now, your typical commercial aircraft travels at a speed of around mock zero point eight, So mock two point seven is wicked fast. It's kind of like around you know, more than two thousand miles per hour or approximately three thousand, three hundred thirty four kilometers per hour. So the suit needed to protect astronauts against the forces they would encounter should they have to eject at that speed, which is pretty crazy stuff. Now, this version of the Space Shuttle had ejection seats for the pilot and copilot, and as they said, those early Shuttle flights only had two astronauts each to make certain that the shuttle was operating at the expected levels and testing it out to make certain it could go into operational status. Now, keep in mind. The purpose of the Shuttle was to serve as a reusable vehicle that we could take to low Earth orbit and then come back to Earth. So the injector seats and the escape suits or standard issue for STS one through STS four, the first four test missions of the Space Shuttle UH Space Shuttle Columbia. I should add the suits would connect to the shuttle for the purposes of life support. And if you ever look at a photo of an astronaut wearing one of these, you'd say that is non attractive space suit because they kind of look like lumpy potatoes. They weren't designed for use outside the shuttle in space, so they lacked the various layers of thermal protection and teflon coding and whatnot to protect against like micro meteoroids and the extremes of temperature that you would find in outer space. There would be no need to worry about that stuff until a bit later with the first Shuttle based e v A s. The pressure suits did have bladders in the legs, so they were partially pressurized. They're pressurized in the lower body, and again this was to provide the pressure needed to keep blood from pooling in the lower extremities during times of extreme acceleration. So this helps protect against blackouts. Right, if all your blood starts rushing to the lower part of your your body, then there's not enough in your brain to keep you, you know, conscious. So this pressure helped prevent against that. It helped kind of put enough pressure on the lower limbs so that blood couldn't pool down in the lower body. I talked about it a bit in our previous episodes. After the first four test flight missions of the Space Shuttle, NASA made a few changes, and for one thing, they got rid of the ejection seats in the Shuttle, which meant that the suits really weren't a fit anymore either, because the whole reason to have the suits was as a protective outfit in the event of having to eject out of the Shuttle, so they got rid of them starting with STS five, the fifth flight of the Space Shuttle Columbia and the first operational flight, meaning the first to actually be considered more than a test flight. This was one that was delivering a payload to outer space. The cruise on that vessel didn't wear pressurized suits during takeoff and landing or launch and re entry. Slash landing. They had simple flight suit. They were blue in color, They weren't pressurized. They did have helmets to protect their noggins for launch and re entry and landing, but they weren't wearing any sort of pressurized suit with life support. NASA was sort of following the old Soviet model, which for many years did not have cosmonauts wearing pressurized suits until there was this tragic decompression accident that changed things. As it turns out, a similar tragedy would change NASA's approach a few years later. Now, I don't really have much to say about the blue flight suits because they didn't really represent a lot of tech, and really they showed that NASA had a high level of confidence in the safety and operation of the Shuttle. But I can talk about the new extra vehicular Activity or e v A space suits. NASA planned to have two astronauts go on a spacewalk during STS five, but some health issues delayed that, and then a technical error in one of the suits put those plans on ice until STS six, the sixth mission that would end up being the maiden flight of the Shuttle Challenger. And yeah, both Columbia and Challenger have tragic ends, but STS six was a success, and during that mission, astronauts put the new extra vehicular Mobility Unit or EMU to the test. Let's talk about those. So one big change with the e m U or EMU was what was worn underneath it, specifically the mag or MG that stands for maximum absorbancy garment. And if you think that sounds like a diaper, it depends. Now you're on the right track. Gone were the days of the urine collection devices because those were meant to work with male astronauts and the space program had finally evolved beyond being a men only endeavor. After this, you know garment, you would slide on a one piece thermal garment called the Thermal Control undergarment. It's kind like a body suit or long John's. And then came the Liquid Cooling and Ventilation Garment or l c VG, similar to the one that was worn by Apollo astronauts. This is the thing that allows cool water to run through tubes that are against the garment and help, you know, maintain a good body temperature for the astronaut. The suit had a few other pieces to it. The two big ones were the lower torso assembly or l t A, and then you had the hard upper torso or h U T hut so as the name implies, the hard upper torso. First of all, it was for the upper torso so like the chest and shoulders and stomach even and it had a rigid body structure made out of fiberglass which could hold in the pressure of the suit and not have it balloon outward. So instead of using like a tough, tight material to restrain ballooning, this was just a you know, a hard material. It didn't flex in all. UH the arms of the suit, the helmet, and the lower torso assembly all would connect to the h UT, as did the p l SS UH, the primary life support system officially known as that now, and the display controls module would also mount on the front. This is the sort of Darth Vader looking collection of UH indicators and and controls. Also, the HUT would hold a bag filled with drinkable liquid with a straw that would extend up to the helmet of the astronaut, because even in space it's important to stay hydrated. Ultimately, NASA only produced three sizes of the HUT, which meant, in turn that the organization had a limited number of choices when it came to which astronauts would be able to go on e v A s, because the suit was not a one size fits all kind of deal, nor was NASA planning on custom building a suit for every astronaut. The exterior of the EMU is bright white, part to reflect heat and partly so that the astronaut is extremely visible against the blackness of space. And in total, the suit has fourteen layers, from the liquid cooling layers are closest to the astronaut skin, to a pressure suit layer, to a restraint layer to keep that pressure in check, to a neopreen layer to hold everything in, to seven layers of micro meteoroid and thermal protective material, and an outer layer of kevlar nomes and gortex. Alright, so an astronaut going on a n e v A would first put on their you know there under suit, but then they would put on the l t A the lower half of this suit, the leggings and boots and you know stuff that comes up to the hips essentially, and this half is the soft half. It's the pliable half at least when it's not pressurized. And then they would put on the hut, the upper half and seal those two together. They lock in together and have a ceiling layer that was used necessary obviously you want to keep a seal airtight. Then they would put on their snoopy cap. This is a close fitting head covering that incorporates speakers and a microphone that allows for communications with others. Then they would seal on the gloves and helmet. Then the suit would pressure eye, the p L S S would activate, and then you would have your astronaut ready to go. Not only took around fifteen minutes to get into or out of the suit from beginning to end, but the process of going on an e V A would require a lot more prep work than just getting into gear. Like you had the whole pre breathe exercise you had to do too, alright, So connecting the p L S S to the suit, there was another element on the e M you called the electrical harness or e e H or EMU electrical harness. This was worn inside the suit, but with connections to link the p L S S to the stuit itself, so all the systems would be interconnected. The helmet had various visors to protect against stuff like sunlight. It also had mounted headlamps and could accommodate a TV camera transmitter as well, so that you could get that glorious first person astronaut view. While the David Clark Company made the pressurized suits for the early test flights of the Space Shuttle, the e m U was the product of two other companies. One was Hamilton's Standard and the other was I L C. Dover. And while the first real use of the e MU was aboard the STS six after the failed attempt on STS five, I should also add that they actually had one of these suits on STS four during one of the test flights, and they practiced the process of putting the suit on and taking it off in zero G to make sure that there weren't any other issues that need to be worked out. They didn't take it on a n E v A, they didn't leave the shuttle, but they did practice getting into and out of it. The e MU design would evolve a little bit over the years, but to this day there are still e m U s aboard the Internet Space Station. And when you think about that, like how old these things are, that's something right. The ones they're actually have a little bit more of a modular design, which gives astronauts the ability to change the fitting slightly, which helps them accommodate different body sizes and types. At least to an extent, the hut still kind of limits things a bit in that regard. I should also mention that these things are pretty heavy, at least back here on Earth. They're heavy in space. You don't really have to worry about it. Wait, it's not so much a thing you gotta worry when you're in, you know, a microgravity environment. But if you were to suit up down here, you probably wouldn't be going on any sprints or anything like that. That's because the Shuttle version of the e v A weighed in and around two pounds, around a little less than a hundreds, and the version that would be worn aboard the I S S was even heftier. That was three nineteen pounds or around a hundred. One other thing I want to cover before we go to break is the m m YOU or manned maneuvering unit. This was a propulsion unit that fit over the life support system that you wore on your back when you were in an e m U. This was kind of like a jet pack for space, although not using you know, thrusters with ignited fuel instead using nitrogen gas as a propellant. And there were twenty four nozzles on the m m U, so you could use the combination of nozzles to kind of maneuver your way and float through space with this backpack and not have any other connection to the spacecraft, like no teather, just floating around out there. Uh. You would use a hand controls on the MMU to kind of guide where you wanted to go. Bruce McCandless did this Ino, and there's a famous photo of him looking back at the Shuttle with nothing connecting him to the spacecraft as he just floats above the Earth. And if I think about it too much while I'm looking at that picture, I actually start to feel anxiety. Is an incredible photo. The MMU was used on only three missions before NASA retired it, and the reason the agency sunseted the MMU was the same reason that the Blue jumpsuit era would come to an end. It would be a disaster that would change everything, but we'll talk about that after this quick break. On January nine, the Space Shuttle Challenger broke apart seventy three seconds after launch, killing all aboard This was one of those big defining moments in history, history in general, not just the space industry. For one thing, as a launch, multiple news outlets were covering the story live in real time, and so the world saw this explosion happen. For another, NASA had really promoted this mission heavily, part because a high school teacher, Krista, she was part of the crew and she would have been the first teacher in space. And for that reason, it was something a lot of schools were showing live on on televisions. In the whole generation of school kids were exposed to this tragic disaster in real time. And I mean I was one of them. I was ten when it happened. I could do a full episode about that mission and what happened as a result of that disaster, But for our purposes, let's just stick to the suits. NASA grounded the Space Shuttle program and conducted a full investigation and evaluation of the program. No Space Shuttle missions flew for two years and eight months, and when the program returned, so did pressurized flight suits. Astronauts had to wear these suits for launch and for re entry and landing, so once again they had to wear a specific suit for those moments in a mission. They were officially called the launch entry suit. These new suits would get the nickname pumpkin suits because they were bright orange in color, and the thinking was that in an emergency evacuation, they would likely be over water and the bright orange color would make the suits really easy to spot against the ocean. The suits had partial pressurization, they were not fully pressurized, so again around the legs to prevent blackouts. So similar to the ejection suits that were worn in the test flights of the Space Shell for Sts one through four, the gloves for the suits would actually just zipper onto the suits themselves. They did not have like the ring locking mechanism that other suits did. They came with a helmet with a polycarbonate face plate that could seal onto the neck of the suit. The astronauts also wore heavy duty boots in addition to the suit, and they had a survival backpack which included stuff like a parachute and a life raft, among some other things. As space suits go, this one kind of sat between the emergency ejection suits of the early Shuttle tests and the jumpsuit that astronauts wore up to the Challenger disaster. They were kind of smacked out in the middle. These suits remained in use until the mid nineties, when NASA would replace them with the Advanced Crew Escape Suit or ACES a c S. These are also called pumpkin suits they also because they're bright orange, but they are puffier than the ELIS suits that came before them, so unlike the l E S the ACES suits for the later spatial era, they were in our full pressure suits. They aren't just partially pressurized, so rather than having zippered connections for the gloves, the gloves lock on through lock rings, much like E m U suits do. They also include a liquid cooling mechanism to help with body temperature, so we're back to that as well, and the ACES suit has a detachable helmet and also comes complete with a survival backpack, similar to the l E S. Like the l E S, astronauts would wear the ACES suit during launch and re entry and landing. It's very similar to the so Cool suits that the Russians use. Uh the Russians suit helmet is permanently attached to the suit, and there's no backpack on the so called suits because there's not enough room in a Soyuz capsule to handle one. But these are the suits that have been in use long after the Shuttle program has come to an end. And now let's talk a little bit about some planned suits, including a couple that never entered into service. One of those was the Constellation space suits. I shouldn't say one two of them were Constellation space suits because there were two different versions. So the Constellation project was meant to pick up where the Space Shuttle was leaving off, with the idea being that the new spacecraft would take astronauts to and from the International Space Station and ultimately to the Moon, hopefully by twenty twenty. This would be the Orion spacecraft. And if you are paying attention, you know that came and went and no one was going to the moon. Well, the Constellation program ultimately got the acts after a full review of the program revealed that it would be unsuccessful without a substantial increase in the budget. But had it gone ahead, we would have seen a new type of space suit meant to be worn both during critical maneuvers such as during launch and reentry, as well as for e v A s. So, in other words, astronauts would have an indoor outdoor space suit, and there were two planned configurations of this suit. Configuration one would have covered most missions with a full pressure suit that included a closed loop environmental system allowing for operation in space, and like some of the older suits I've talked about, this one would connect to the Orion spacecraft's life support system through an umbilical tether rather than incorporating its own p L s US. The second configuration was planned for lunar missions. This was more of a heavy duty one. The suit would make use of the same arms, legs, boots, helmet, and gloves as Configuration one's suit, but to have a different torso section. It would also allow for higher pressure within the suit, something that could head off issues like decompression sickness, which I mentioned about earlier, the bends, that kind of thing. While the US discontinued the Constellation program in two, NASA continued to develop the Constellation space suit, but simultaneously, a different department within NASA was working on the Advanced Space Suit project. So you had two different space suit programs working at the same time. Let's talk about this Advanced Space Suit Project one. The initiative developed two designs for e v A suits. The Z one and the Z two. The Z one uses a soft suit approach, meaning you know, it's mostly pliable when it's not pressurized. It has some hard components, but it's mostly fabric. Has a large dome shaped helmet attached to the suit. Kind of looks like buzz Lightyear. In fact, the white suit has like some green lines on it and all the pictures of it, so it really does look like a buzz light ear suit. And it splits into upper and lower torso segments as well as having assembly mechanisms for gloves and boots to attach to the suit. The Z two has a hard upper torso rather than a soft one, so it's similar to the E m U suit I mentioned earlier. In addition to the Z one and Z two, the projects spawned an updated p l SS. This one was called the Next Generation Life Support where in g l S complete with an improved method for removing carbon dioxide phone the suit's air supply. In sixteen, NASA made the decision to combine the information that had been learned from the Constellation project as well as the Advanced Space Suit Project and create a new one kind of like Vultron. All this joining together to find the x e m U project ZIMU, I guess or x AMU if you prefer uh. This is the specific project that the audit found to be behind schedule, to the point that the Artemis programming, which we were supposed to go back to the Moon by twenty four is not going to happen at least not on that timetable. In fact, according to the report, these suits will not be ready until April at the earliest. That's if everything goes right. The report on those suits is available online and it is heck and thorough, y'all. In that report, we learned that the Constellation suit program cost a hundred thirty five points seven million bucks before it came to an end, the Advanced Space Suit pro project that costs another fifty one point six million dollars, and the x EMU has cost so far around two hundred thirty two point eight million dollars. I did the math, and that means that NASA has spent more than four hundred twenty million dollars on the next generation of space suits already four twenty NASA is just blazing through that cash, and according to the report, it's not even halfway to what will ultimately get spent on these suits before they are fully built, tested and deployed. Yeza. Still, when you're talking about keeping people alive in space, it's obviously it's gonna cost a lot of money. But what happened, well, that's complicated. So one bit is that there are multiple offices or departments within NASA responsible for space suit development. They aren't always working on the same projects or with each other, so you've got a lot of overlap. Potentially you've got a lot of potential wasted effort because it's not a unified approach. This doesn't mean that it's always a bad thing, because you can often get really good ideas coming out of totally different groups that would would have died on the vine if it had been a unified project. But it does make it more complicated. So like this is like when NASA side that the Constellation program and the Advanced Space Suit program needed to kind of combine into each other. For another. As I mentioned before, NASA is an organization that sees a lot of changes every year. For one thing, there's always a political battle over NASA's funding. Any agency that's dependent upon federal funds is going to find it hard to stay on track because support can fluctuate from year to year. You might get a year where you get more financial support and another year where no one is really supporting you, and that makes it really hard to stay on task with projects. For another, the head of NASA gets their position courtesy of whomever happens to be president, so that means leadership and NASA changes fairly regularly, and that can mean projects that were in progress might end up being put on the back shelf or even getting the acts. NASA, I want to add, is an incredible agency. There are countless people devoted to the pursuit of science and knowledge who are working there. They are innovating, they're solving problems that are really spectacular problems. But they also have to work in a system that isn't always dependable or stable. Right like, things change, priorities change, leadership changes, and this sometimes means that something that was in development gets taken off development. And when you add to that the normal challenges of just trying to create technology with all the designing and testing and then the redesigning and rebuilding and retesting and all of that effort, particularly for technology that's meant to help keep people alive in an environment that is trying to kill you, and you can see why there are issues. My hope is that we will see the x E m U suits emerge. We need them, the I S S needs them, and there are some cool things that they're supposed to incorporate. Now. I'm holding off on going into detail about all that because, as we've seen, sometimes stuff that we plan for just doesn't pan out, like a feature that was considered to be critical ends up getting cut. So I don't want to cover all the things that are planned for it. I want to wait to see what happens. But believe me, if we get to a point where we've got a working x E m U suit ready to go into service, I will come back to this topic and we will do a full episode on it, and that ends our journey about the evolution of space suits. So far, I didn't really cover the private space suits sector. I might do that in a future episode at some point. Um It's one that I have mixed feelings about because I often feel that people like Elon musk Um dismiss how hard this is to do safely and properly. But on the other hand, there is something to be said about having the entire process under the control of a single company. So there are advantages to the private space approach that a federally funded agency like NASA cannot take advantage of. That that much is true. I just don't know that musk boasting that he could get it done through SpaceX and take care of NASA's space suit problem is really that accurate. But who am I to say maybe they'll be able to do it. We'll have to wait and see, and that's it. If you have suggestions for topics I should cover on future episodes of tech Stuff, whether it's a company, technology, a trend in tech. Maybe it's just something you want to know more about, let me know on Twitter the handle for the show it's tech Stuff h s W and I'll talk to you again really soon. Text Stuff is an I Heart Radio production. For more podcasts from my Heart Radio, visit the i Heart Radio app, Apple Podcasts, or wherever you listen to your favorite shows.