The First Manned Spacecraft

And I'm gonna do that, but it really sent me down a very long rabbit hole, and I thought it might be fun to look at some of the early manned spacecraft and a couple of the unmanned ones to that preceded the Space Shuttle programs. So we're actually gonna do a block of space related episodes. This is the first one. We're gonna have several more, including ones about different eras of space exploration, the different rockets that have been used in space exploration, and the Space Shuttle program.

So we're blasting off into out space for a few episodes. I hope you enjoy the ride. Now, before I get started, I want to give you guys some trigger warnings early on in this episode. So I'll be talking a bit about some early space missions that involve animals, and not all of those are happy stories. So if you are distressed by sad stories about animals, and there is one coming up later in this episode, I'll point it out when I get to that section, just be aware that

that's going to happen. And second trigger warning, I'm one of those people who gets distressed about sad stories about animals. So if you get distressed by bald tech podcasters who are barely able to keep it together on microphone because they're talking about a sweet doggie, then this is your

trigger warning for that as well. Before there were spacecraft with actual human beings in them, there were many earlier experiments and projects and thought experiments that provided valuable information about what it would take to get people into space. The scientists and engineers responsible for those experiments came from all over, and much of their work was advanced not

through a pursuit of knowledge but through conflict. And I've mentioned this in other episodes, but the space race was largely fueled by pretty ugly political rivalries and a need to demonstrate a position of technological dominance and capability. Now, I don't say that to diminish the incredible contributions of countless individuals who have dedicated their lives to exploring the unknown, whether it is piloting a spacecraft or working on Earth

so that others can do that. I I say it to illustrate that much of the work they did was made possible because the people in charge of the purse strings, the ones who were actually paying the checks, were really interested in their country being seen as the most powerful and more importantly unassailable entity on Earth. So double edged sword. Before I talk about any specific spacecraft, I want to give an overview about some of the early scientists and

engineers who helped pave the way. Now, I could go all the way back to the Renaissance, when folks like Galileo made astronomical observations that challenged the prevailing geocentric view of the universe, but that would make this show way too long, and I've already got five episodes planned in this block. I don't need to add more to them, so I'm gonna skip ahead of bit. One person I do feel I must mention published a work at the end of the nineteenth century that was incredibly important. His

name was Konstantine Siolkovsky, a Russian scientist. In eighteen ninety six, he began writing a work the English title of this work is Exploration of Cosmic Space by means of Reaction Devices, and essentially Siolkovsky was working out the logistics of escaping Earth's gravity, going to space and using rockets to do it. He did this at a time when Russia was still

under the control of the Czar. In fact, it really wasn't an after the Russian Revolution of nineteen seventeen in the formation of the Soviet Union in nineteen twenty two that Siolkovsky really received any support for his work. The Soviet government was very interested in rockets that could go really, really far. Siolkovsky wasn't just a theorist either. He would

also test his ideas. He introduced the concept of using wind tunnels to judge rocket aerodynamic design, for example, so he was practical as well well as a theoretical physicist. Over in the United States, meanwhile, a physicist named Robert Goddard was also working out the requirements to send a rocket to space. He he came out along a little

bit after Sulkovsky. He also invented liquid fueled rockets. He received patents for his designs in nineteen fourteen, and he build the first working liquid fueled rocket In the mid nineteen twenties. He pioneered work in elements like gyroscopic control to help with flight stability, and also power driven fuel pumps for fuel managed it and a couple of years later scientists in Europe would create similar designs, largely independently, which would be put to use in Germany's V two

rockets during World War Two. The V two is short for fair Gel tongs FAFA s VY or retribution weapon to which, yeah, that kind of tells you the purpose of that particular piece of technology. It was not meant to explore space, however. On June twenty, nineteen forty four, engineers conducted a test of a V two rocket that saw it reach an altitude of one D seventy six kilometers. That made the V two the first rocket to cross the Carmen line, which you could call the edge of space.

The Carmen line is at a hundred kilometers above mean sea level, and it's named after Theodore Fawn Karmen, who was an Hungarian American engineer. He proposed that that altitude would mark the point where it would be impossible to maintain your your flight through UH lift alone at least through conventional means, because the atmosphere would be too thin to support an aircraft via lift unless the aircraft were

actually traveling faster than orbital velocity. Now, interestingly, in the United States, it doesn't take as far to get up to space. You don't have to go up to a hundred kilometers to be in space. Now, I don't mean that space is magically closer to the United States soil or anything. Rather, I mean the United States Air Force calls anyone who has traveled at an altitude higher than eighty kilometers over sea level an astronaut. So if you go higher than eighty kilometers and you're in the U. S.

Air Force, you're an astronaut. If you are anywhere else in the world, they would say, you haven't actually been to space yet. You need to go another twenty kilometers. But I just thought that was an interesting little side point. At the end of World War Two, there was a scramble among allied powers to grab up some of the more important assets that were formally held by the excess powers.

Two of the assets that the United States really wanted were the V two rockets Germany had been using to bombard various countries and the scientists who had helped design those rockets, and the US did not want to put the scientists on trial for developing weapons of mass destruction, even though they had killed countless civilians. Instead, they wanted those scientists to build rockets for the good old U.

S of A. This was called Operation paper Clip. In ninety six, the United States launched some V two rockets to the edge of space, but that would be the U. S. Air Force definition of the edge of space, meaning it was around eighty kilometers altitude, not a hundred and work on the V two lead to the development of two stage rockets, which, as their name suggests, means the rockets have two segments designed to provide the energy needed to

boost the rocket out into space. I'll cover more details about rockets and stage rockets and what that all means in an upcoming episode of tech Stuff. Now here's the part of the episode where I get really sad, the bit that I warned you about earlier, because I'm a softie and I love dogs, so this could be a little hard for me to get through. It was hard for me to research, and right I don't know if it's gonna be hard for me to talk about. But we'll find out together. So just take my hand. We'll

make it through this. Beginning in the early nineteen fifties, the Soy Union began to experiment with simple spacecraft capsules, and they put dogs in these capsules to test and see if it might be viable to send a human into space. No one was really sure yet. The first two dogs to do this were named Desik and Saigon. These were both put in very tiny capsules. They were actually trained by being put into increasingly smaller crates over prolonged periods of time, because they would have to sit

in these very tiny capsules for quite some time. They were carried by our one rockets to an altitude of one kilometers, which meant that they were actually crossing the carm online. They were not going into orbit though, they were just going very very high up into the atmosphere and then coming back down. They were in special pressure suits and they were inside a little pressurized cabin, so

the case they were in was a pressurized case. Both of them returned from that first test flight alive and well. On July twenty, nineteen fifty one. Desert would be put on another test flight on July one with another dog named Lisa. But at that occasion we weren't so lucky. The two dogs died when the parachute for their capsule failed to deploy. Saigon, however, would be adopted by a Soviet scientist and would not go on any more flights and lived out her life fine. The Soviets did several

more tests. They gradually would increase the altitudes until they reached about four fifty kilometers and by then they were using our five A rockets in the late nineteen fifties, and then there was like okay. So on October four, ninety seven, the Oviots launched sput Nick one that was the first man made satellite to reach Earth orbit, to actually orbit the Earth in full. It was a silver sphere that went beep. That's essentially all it did. It sent out a radio signal and it orbited the Earth.

It was also a huge wake up call to people in the United States. Scientists and government officials had known about Russian work in the space program and also about their advances in rocketry for a while. But sput Nick, which could be detected by amateur radio operators and it was ham operators were detecting this satellite in real time as it crossed overhead. It was proof the Soviets could put something up into space that could travel to the

other side of the world. And if they could do it with a sphere what went beep, they might be able to do it with a bomb. And this was when the USSR and the USA were engaged in a Cold war, so this was a big deal. It really lit fires in the United States, not just in the space program, but for a host of other technological research projects, some of which would even evolve into stuff like the Internet. So that's spot Nick one, and I did a full episode on it in the past, so I'm not going

to go into further detail right here. When we come back after I've stealed myself, will tell the sad story of sput Nick two and like a But first let's take a quick break and thank our sponsor. So Sputnik

one was an unmanned satellite. Sputnik two would be the first spacecraft to carry a living creature inside of it and go into Earth orbit, and that living creature was like a spot Nick two launched on November third, nineteen fifty seven, just a month after Sputnik one launched, and inside the capsule was like a a dog that would become the first animal to into Earth orbit, and unlike the earlier tests with dogs, this was a one way ticket from the beginning. The other experiments were designed in

an effort to ensure the dog's survival. The scientists wanted the dogs to come back down and and safely land, but they had no such plans for spot Nick two. Like it was going to go up into orbit, and the Soviets didn't have any way to bring her back down safely. They knew the satellite would encounter drag, it would lose speed, it would eventually have its orbit decay, and the spacecraft would re enter their atmosphere. They had no way of controlling its descent or mitigating the problems

of heat build up. Like, uh, no matter what, was not going to survive that trip. She didn't live very long. When she died is actually a matter of some mystery. The Soviet Union originally reported that she actually survived a full week in orbit, which is kind of horrifying to me. But equally horrifying are the points of evidence that point other wise. Later documents said she died only a few

hours after launch. Because the temperature inside the capsule reached more than a hundred degrees, the forces she endured were pretty rough. Uh. Data from Spotnik two indicates the capsule's temperature increased after it orbited the Earth three times, and

that was the beginning of the end for her. And the story really rips me up every time I think about it, because, on the one hand, I certainly understand the need to test whether or not it might be possible to send a person to space and into orbits safely. That is a huge, huge risk, and it was full of unknowns. We had never done it before, so you have to be sure that's going to be safe before

you put a human life at risk. And it's not like we had the technological capabilities at that time to do this without an actual organism on board to see what happens to that organism. But it's still a really hard story for me to get through. Ole Gazinco, who was one of the scientists who worked on spot Nick two, would later say that the mission wasn't designed to gather

sufficient information that would justify the death of Lyca. He expressed regret in his involvement and the decision to sacrifice, or essentially said we didn't get enough information from this experiment to justify killing an animal in this way. By the way, Laca's legacy lives on in multiple forms of media. There's nick about Ziz novel Likeca, it's a fictional account of her story. The animation studio Lika is named after her. That's the studio that did films like Coraline and Cubo

and The Two Strings. There are poems about her. There are songs, and my favorite in case you want to listen, but I warn you it is emotional as a sad song by Jonathan Colton. It's called Space Doggedy. It's actually an homage to David Bowie's Space Oddity song. He was given a challenge to transform a song and the specific song was Space Audity Audity by David Bowie. So he took that and he said, I'm known for doing all these songs about monkeys, so I wasn't going to do

one about the first monkey in Space. I decided to do one about the first dog. And it's a really sweet song. If you're a dog lover, it's uh, it's it's very sad, but it's worth a Lessen. It's a very good song, all right. I gotta get it back together and talk more about spacecraft. So we're through with the animal cruelty stuff. I think while spot Nick two did not gather that much useful information, it did show that was possible to keep a living organism alive in

orbit barring technological failures. And so now the race was on to see who could get a human being into orbit first. Over in the United States, efforts were rushing along with the Mercury program. Understandably, there were many launches with unmanned versions of the Mercury capsule. They wanted to test its space worthiness before ever putting an actual human being inside of it and sending that human off into space. And there was one test with a special pilot. It

was for the Mercury Redstone to mission. Mercury missions were given different designations. The Mercury Redstone missions were suborbital, meaning these were tests where the Mercury capsule was sent up into space, but not into an orbit around the Earth. It would just go up and then come back down. This was late in the testing phase, after they had fired off multiple Mercury capsules that were unmanned. The special pilot was a chimpanzee later named Ham. Ham's name comes

from the lab that trained him for the mission. It's the Holloman Aerospace Medical Center, so it was kind of an acronym. Ham was trained to activate switches when presented with the stimulus of a lit indicator, so a light lights up and the chimpanzee would reach out and hit a switch. It was trained this way. He was trained this way by he was given a banana pellets whenever

he did it correctly, so he was rewarded. If he didn't do it, he would get a very mild electric shock on his feet, which sounds pretty awful, but it was mild. It was not something that was enough to harm him, but to you know, to sting a bit

and and to essentially train him into this behavior. The whole point of it was the the the medical center wanted to train Ham to perform repetitive routine tasks and to be able to do it on command, because they weren't sure what would happen when someone was in orbit. Would they maintain that ability, would they be able to continue to do these routine tasks while they were in orbit, or would weightlessness affect you in such a way that

you you were no longer able to do this. Because if you put a pilot up into orbit and it turns out after a short while that weightlessness or micro gravity, if you want to be more specific, has a negative effect, then you could condemn that person to die because are no longer able to do whatever they need to do in order to return to Earth safely. So this was a test to see would waitlessness or microgravity have that

negative impact on cognitive abilities. So Ham got trained in this way, learned how to flip switches according to lights being lit up. Ham was not, by the way, piloting anything. Ham was again acting acting on these little these little lights that would blink on a console and would react to that. On January thirty one, nineteen sixty one, Ham who at that point did not actually have a name yet because NASA thought it might be a bad idea to name the chimpanzee just in case something did go wrong.

If something went wrong and they had named the chimpanze, it would create kind of an emotional anchor point that might make it even more difficult to move forward with the space program. So he was just number sixty five until he came back anyway, he got into a mercury capsule, or was put into a mercury capsule. I should say, I'll talk more about what those capsules were like in just a little bit. And he would perform his duties of switching switches on command pretty much as he would

on Earth. So he sent up into orbit, and he saw the little lights, and he flipped the little switches, and apparently it was pretty much the same as he would have done back at home. It was a little slower, but not by much. It was like a split second, So it wasn't it wasn't statistically important. It appeared that the rigors of space and effects of microgravity were not negatively impacting his ability to think and react in that way, which was a relief because there were also other issues

that happened that fortunately did not affect Ham's health. For one thing, the spacecraft lost air pressure. There was a problem, a breach, but Ham Ham was inside a pressure aze capsule inside the spacecraft. The capsule part maintained its pressure, so while the spacecraft itself lost some air pressure, Ham was still safe inside. His flight was suborbital. It did not go all the way up into orbit. It lasted

about sixteen and a half minutes long. He landed safely in the ocean, because that's how the mercury capsules were designed to make an ocean landing. There was a bit of a scare because the capsule had that small breach it actually started or not the capsule, but the spacecraft had that small breaches actually started filling up with water upon landing in the ocean. But the retrieval crew was able to get to Ham in plenty of time, and

so Ham was extracted from the spacecraft. There was otherwise a danger that Ham, really very real danger that Ham could have drowned if they hadn't gotten to him in time. Uh. He then was transitioned to live out most of his life at the National Zoo in Washington, d C. Part of the Smithsonian, but in nineteen eighty was transferred to the North Carolina Zoo, and that's where he passed away on January nineteenth. And he was in his mid twenties,

probably twenty five or twenty six. It's actually pretty young for a chimpanzee, which can live up to age fifty. Not entirely certain what caused his demise. I don't know if he just got a disease or what. I couldn't find a whole lot of information about what led to that, but uh, he did get that name upon landing, and

he made history is the first non human hominid in space. Meanwhile, over in the Soviet Union there was the Vostok program that was going strong, So Mercury was starting to work with these unmanned missions and the one with the chimpanzee. Over in the Soviet Union there was a push to go toward into space with a program called Vostok v O S t O K. The Vostok looked like kind of a giant circuitry component to me. There was a re entry capsule that's where the crew member would say.

It was a one person spacecraft, and that was a sphere essentially, and then had sort of a conical base to it. That's where the retro rocket would be, and it was supposed to jettice and off the spherical part. And the sphere was two point three meters in diameter that's about seven and a half feet in diameter, So the cosmonaut didn't have a whole lot of room inside, but it wasn't the most cramped quarters of any spacecraft,

it did have some odd designs to it. Apparently, the instrumentation was at a ninety degree angle from the the forward facing position of the cosmonaut, meaning that the cosmonaut was going to have to turn his or her head ninety degrees in order to see the instrumentation panel. That seems like a weird design to me, but that's, I guess,

just the product of having to do this so quickly. Also, there was an important part of figuring out where to distribute the weight in this spacecraft see its spherical because there was no way to control the capsule's path and orientation once it re entered Earth's atmosphere and separated from its engine system that was in that that conical section.

The sphere icle design meant it had to be shielded on all sides because there was no way to be absolutely certain how it might be oriented once it began to descend. The best the Soviets could do was designed the sphere in such a way that the equipment inside would offset the center, the natural center of gravity for the vehicle, and thus create a tendency for it to

maneuver into a predictable orientation. Also, the cosmonaut was meant to actually eject from the capsule during descent, once reaching an altitude of seven kilometers. From there, the cosmonaut would float on down with a parachute and the capsule would land on its own. The Soviets didn't quite have time to develop a capsule that could descend gently enough to ensure the survival of the human inside of it, so

this was a necessary step. It wasn't like an emergency UH procedure, although the Soviet Union did call it that for a while. This was actually normal practice was that the cosmonaut would eject from the spacecraft at seven kilometers

and then parachute down by themselves. The Vostostom had a retro rocket designed to slow the spacecraft down enough in orbit to purposefully re enter the urt atmosphere, and if that failed, the spacecraft would likely remain in orbit for up to ten days, so cosmonauts were given enough food and oxygen to last that long just in case. In

other words, there was no backup system. If the retro rocket failed, then the cosmonaut was going to be forced to sit there and wait until the orbital decay of the spacecraft was enough for it to force it to go and land or or re enter the r atmosphere, and there was no real predicting where that might happen at that point. Really, it's it would be based upon uh, well, whatever the actual speed of the spacecraft was and it's

orbital altitude at that point. But yeah, it's kind of scary to think there was no backup system to re enter into the Earth's atmosphere in a controlled way, and that it might just require you to wait it out for ten days, also in a spacecraft that had notoriously bad waste removal systems. I'll leave it at that. On that happy note, let's take another quick break and thank our sponsors. Al right, backtracking a little bit, the first organisms to launch into orbit and return alive were an

early prototype of this Vostok capsule. It was the Vostok one K model that carried them. It was the corrible spot Nick two, which in the West we call spot Nick five. That was the specific mission to carry animals into orbit and return safely, uh and did so successfully. It launched August nineteen, nineteen sixty and it carried Belka and Stroka, two dogs, plus it had a couple of rats in there. A whole bunch of mice and some plants. It completed three orbits of the Earth and then it

returned safely, so everyone lived on that one. The first human flight into orbit was aboard a Vostok three K A spacecraft which had the official name Vostok one. And I know that's confusing, because the Vostok one K was a type of spacecraft. Wasn't the name that was a classification. The Vostok one was the name of a spacecraft, but it's classification was Vostok three K A YEA. The cosmonauta board that flight was Uri Gagarin, and he launched into

the heavens on April twelve, nineteen sixty one. He was the first of six manned flights aboard the Vostok three K A spacecraft model. The sixth one of those flights actually saw Valentina Tereshkova, the first woman in space. She launched on June six, nineteen sixty three. The Vostok one spacecraft had manual pilot controls, but they were meant to

be used only in the case of an emergency. The plan was that all the controls of the space craft would happen automatically or would be issued from ground control, and the fear was that no one was really sure what space flight was going to do to a person's ability to think and react. It's that same thing that the United States was trying to test with the chimpanzee.

So it could be that weightlessness could cause some sort of space madness, or maybe the pilot just gets disoriented to the point where that control of the spacecraft would be in danger. So the manual controls were only supposed to be activated by initiating a code sequence aboard the spacecraft, and the pilot was not supposed to be told what

the code was unless there was an emergency. So if it became necessary, ground control could send up a message to URI and say, hey, here's the code sequence you need in order to take manual control of your spacecraft. However, as it turns out, at least one person gave URI the code before you even got into the capsule, just in case. The Volstock one would launch at six o seven a m. Ten minutes after launch, Uri was in orbit.

He made one orbit of the Earth, and at seven twenty five AM or thereabouts, his spacecraft's retro rocket fired to slow down the spacecraft enough for re entry, and things went a bit scary at first. The reentry model for the Vostok one is that sphere I mentioned earlier, right, It's a sphere that's kind of attached to a conical base. Well, the conical base is supposed to detach from the sphere upon reentry. It's supposed to uh to to separate from

little explosive bolts, but that's not exactly what happened. Part of it ended up sticking to the sphere. It was strapped there. There was a bundle of wires that kept the two pieces tethered together, which complicated matters. The sphere was meant to fall in a very controlled way, but with this added weight that was tethered to it, it was causing lots of gyrations and rotations. I can't imagine what the forces felt like inside the spacecraft as it

was plummeting down and turning unpredictably. URI ended up experiencing forces around eight G. That's eight times the force of gravity we feel here on Earth. But fortunately, through that process, the conical section eventually broke away and the sphere was able to reorient properly, and at seven fifty the reentry model reached the altitude of seven kilometers and your re ejected. His parachute deployed, and he would land in Russia at eight oh five, about two hours after he had launched.

Now a little less than a month after his successful flight and orbit of the Earth aboard the Vostok one, America established a new first. Alan Shepherd became the first person to actually pilot a spacecraft while in space, as opposed to ride in a capsule as more or less a passenger. The mission included both automatic pilot and manual control segments. Shepherd tested the Mercury's flight controls he was

aboard a Mercury capsule. He tested those flight controls to make sure that the spacecraft would react in a way similar to the way they had simulated it back on Earth, and he found that pretty much they reacted the same way the simulations did. Shepherd's historic flight took place on May five, nineteen sixty one, aboard the Mercury spacecraft that

he named the Freedom seven. Each of the commanders of the Gemini spacecraft got to name their own spacecraft, and he called it the Freedom seven, not because it was

the seventh Mercury capsule. It wasn't uh he named of the Freedom seven because seven was the number of astronauts who were originally selected to be part of the Mercury programs, so it was uh the seven referred to the number of astronauts, not to the capsule, and it became tradition all the other Mercury capsule pilots would name their spacecraft a name plus the number seven. Shepherd's flight was a suborbital one, so he did not go high enough or fast enough to go into Earth orbit. He flew up

past the Karmen line and came back down again. His flight was was more of a test flight to make sure that a human pilot could withstand the rigors of space travel and still operate the spacecraft properly. His flight lasted a little more than fifteen minutes. He traveled about three hundred two miles or four eighty six kilometers away from the launch site in Cape Canaveral, Florida. He did go to space. His space spacecraft actually reached an altitude

of a hundred eighty seven and a half kilometers. So let's talk about what that spacecraft was like, not the launch vehicle, the rocket. I'll talk about rockets in another episode, but the spacecraft itself. The Mercury project started in the late nineteen fifties and the goal was putting an American in orbit, preferably before the Soviets did. That obviously didn't work out, but the it did prove ultimately to be a success in more meaningful ways to test love of

technologies that would be incorporated in later space projects. One of those ways was that the US wanted to create a spacecraft that would allow a human operator to control it, including making adjustments to the spaces orientation upon re entry. Rather than go with that spherical approach that the Vostok spacecraft had, the Mercury is more of a cone shape. It's something that would be repeated with the Gemini or

if you prefer, Giminy and Apollo spacecraft capsules. This helped reduce the surface area that they had to coat with heat shielding. Instead of coding the whole thing with heavy heat shielding, they just put on the base of this cone that was the part of the craft that would face the Earth at an angle while going through the descent, so it was the base of it that had to be heavily shielded against heat. The Mercury capsule was three

point three meters long or ten point eight feet. It was one point eight meters wide that's about six ft, and the bottom side, the wise part of the spacecraft, the part that's pointed towards the ground, had the heat shield on it, and unlike the Vostok, the astronaut inside the Mercury was meant to stay in during the entire descent. They were not meant to eject from the spacecraft. So the Mercury would deploy a pair of parachutes to control

and slow that descent. The first, which was called a drogue parachute, would release at six thousand four meters or twenty one thousand feet, and it was meant to provide stability during the descent. It really only had a minor effect on slowing down the spacecraft. The second parachute would deploy it three thousand meters or ten thousand feet. That was the one that was meant to slow its descent.

The Mercury was meant to land on water. Most of Earth's surfaces covered by that stuff, so it made sense just before impact the Mercury would deploy what was in effect a giant airbag to help absorb some of the force. Of impact, because while hitting the water sounds like that would be great compared to say, hitting a giant rock, hitting water at high speeds is rough stuff. So why is that? Why is it that when you hit water at a high speed it feels almost like you're hitting

a solid surface. Well, first we need to talk about what makes us get hurt when we fall on solid ground. So it's physics time. When we fall and hit the ground, the ground is effectively hitting us back. That's the force we feel when we fall down and hit the ground. It's equal to the rate of change in momentum with

respect to time. So momentum is equal to mass times velocity, So the mass the amount of stuff that's in motion, and the velocity, which is the speed and direction of travel, and the forces depending upon the rate of change in that value. So we can determine our momentum. We take our mass and we multiply at times the velocity we

were traveling an instant before we make impact. The velocity in this case would be really closely tied to acceleration from gravity unless something pushed us to get us going. But essentially gravity is what we're using as our guide here. Anyway, the important thing here is that the rate of change of momentum is the key, not just momentum, not just how fast you're going, but how quickly you go from

moving that fast to not moving at all. If you slow down gradually, then obviously you don't you don't feel a huge impact. But if you slow down instantly, you feel impact. So you're going a certain speed until you hit the ground and then you've essentially stopped. We're gonna ignore bouncing here, we're just saying splatting. The rate of change of momentum is incredible because you go from whatever the speed was to complete stop and pretty much an instant.

Water is a little different from solid ground, obviously because as a bit of a gift to it, right, if you slide into the water, then there's not a big deal. It's the rate of change in momentum ends up being a little slower than if we hit solid ground. You don't stop instantaneously because we displace water. But displacing water actually takes time because for water to move out the way, it has to push against other molecules of water, and that water has to move and so on. There's a

ripple effect and that requires force and time. The water is one of those pesky substances that really resists compression, so you can't just squish it down. It moves. The molecules have to move out the way. So the more water you attempt to displace in a very short amount of time, the less water you'll actually be able to displace. It's just not going to move all the way fast enough. So as you increase the velocity of a mass and you aim it at water, you see less of a

cushioning effect from the water itself. There's still some Landing on water at a high velocity is not the same as hitting concrete at that same velocity, but the displacement of water will not be sufficient to make the landing a painless one. It's still gonna hit you like it's a solid surface. So the air bags helped take some of that force out, but not all of it, and it would transfer some of the force the air bag

and make the landing inside the Mercury capsule survivable. It wouldn't be gentle, but it wouldn't be as jarring as say, the Vostok capsule would have been if they had used a parachute. So the Mercury spacecraft would then, upon landing in the water, raise an antenna from the top of the spacecraft and sent out radio signals that would alert nearby ships and helicopters where the capsule was so that they could come and retrieve the capsule and more importantly,

the astronaut inside the capsule. Shepherd actually collaborated with the automatic pilot system and this test flight, this early flight wasn't a test flight, this early flight and the Mercury mission, it was an intended design of the Mercury spacecraft. So he used a controller that would send commands to the automatic system to fire rockets in order to get the

spacecraft into the proper orientation for re entry. So essentially he would say, the spacecraft is in this particular orientation, I needed to move from this one to this new orientation, and then the automatic system would try to make those adjustments and turn the spacecraft the way uh Shepherd wanted it to. It didn't go off without a hitch. It was a little bit off, but it wasn't catastrophically off.

The freedom sevens orientation was not quite where NASA wanted it to be, and some of the indicators also failed during the landing process. It gave the incorrect impression that important sequences like the retro rockets jettisoning off the heat shield had not happened, and if that were the case, it could have been a terrible, terrible tragedy. But in fact, the retrorockets had jettisoned off. It's just the indicator light

was not showing that having happened. But NASA was able to verify that in fact, it did happen, and everything turned out to be okay. According to Shepherd, landing in the ocean wasn't that different from feeling like landing a jet on an aircraft carrier is about the same kind of bumpy ride. It wasn't the smoothest experience, but it

was tolerable, so his mission was a success. It probably would have been met with an enormous amount of enthusiasm if it were not for the fact that the Soviet Union had just put a man into orbit just a few weeks earlier. But it did solidify the US approach to space travel, and it prepared the way for more Mercury missions as well as the Gemini and Apollo missions. Now, in our next episode, i'll talk more about the Doose missions, as well as a little bit more about Voss Stock

and UH and mercury. Also, i'll talk about the spacecraft that the Soviets built after the Vostok capsules. In the meantime, if you guys have suggestions for future episodes of tech Stuff, maybe it's a technology or a company or personality and tech I should cover, send me a message. The email address is text stuff at how stuff works dot com, or drop me a line on Facebook or Twitter. The handle for both of those is tech Stuff hs W. Don't forget we have a merchandise store now. Go to

T public dot com slash tech Stuff. That's T e e Public dot com slash tech stuff to check out the merch It's pretty sweet stuff if I do say so myself, and please follow us on Instagram. That's all for me today. I'll talk to you again really soon for more on this and thousands of other topics. Because it how stuff works dot com.