WEBVTT 00:00:00.000 --> 00:00:01.740 You know the image, right? I mean, you've seen 00:00:01.740 --> 00:00:04.480 it a hundred times on a movie screen. A massive 00:00:04.480 --> 00:00:07.700 gleaning space station shaped like a giant wheel. 00:00:07.919 --> 00:00:10.179 just kind of suspended against the black void 00:00:10.179 --> 00:00:13.619 of space. Yeah, usually spinning slowly, gracefully, 00:00:13.839 --> 00:00:16.800 waltzing to some majestic classical music. Exactly. 00:00:17.079 --> 00:00:19.600 And inside, people are walking around, they're 00:00:19.600 --> 00:00:22.300 pouring coffee, having meetings. Their feet are 00:00:22.300 --> 00:00:24.839 planted firmly on the floor, just like they would 00:00:24.839 --> 00:00:27.739 be on Earth. Right. It looks so clean and, you 00:00:27.739 --> 00:00:30.399 know, just so obvious. It really feels like the 00:00:30.399 --> 00:00:33.240 inevitable future of human spaceflight. But then 00:00:33.240 --> 00:00:35.549 you look at reality. Right. You look at the actual 00:00:35.549 --> 00:00:37.850 International Space Station and it looks less 00:00:37.850 --> 00:00:41.259 like a graceful wheel. And way more like this 00:00:41.259 --> 00:00:44.000 chaotic jumble of metal tubes and trusses and 00:00:44.000 --> 00:00:46.020 solar panels. Yeah, it's definitely not a sleek 00:00:46.020 --> 00:00:48.399 wheel. And inside, the astronauts are floating. 00:00:48.560 --> 00:00:50.539 They're pushing themselves off walls to get around. 00:00:50.679 --> 00:00:53.460 Right. So after over a century of dreaming about 00:00:53.460 --> 00:00:56.359 these spinning space cities, we literally do 00:00:56.359 --> 00:00:59.679 not have a single one in actual orbit. The gap 00:00:59.679 --> 00:01:02.539 between our science fiction and our orbital reality 00:01:02.539 --> 00:01:05.920 has, well, it's really never been wider. Welcome 00:01:05.920 --> 00:01:09.000 to our deep dive. For you listening, your mission 00:01:09.000 --> 00:01:11.500 today is to step into the blueprints of the past 00:01:11.500 --> 00:01:14.500 and the physics of the future. We are going to 00:01:14.500 --> 00:01:17.819 sift through historical schematics, decades old 00:01:17.819 --> 00:01:22.500 NASA prototype notes, and, uh... Orbital mechanics. 00:01:22.819 --> 00:01:25.060 We really need to understand exactly how a rotating 00:01:25.060 --> 00:01:27.420 wheel space station works and how incredibly 00:01:27.420 --> 00:01:29.640 close humanity actually came to building one 00:01:29.640 --> 00:01:31.939 Yeah, and we're gonna cover the surprising almost 00:01:31.939 --> 00:01:34.620 counterintuitive reason why we ultimately chose 00:01:34.620 --> 00:01:37.200 not to so, okay Let's unpack this right because 00:01:37.200 --> 00:01:39.439 before we can figure out why these majestic spinning 00:01:39.439 --> 00:01:41.560 wheels aren't currently orbiting over our heads 00:01:41.560 --> 00:01:43.519 We need to understand why we want them up there 00:01:43.519 --> 00:01:45.519 in the first place exactly the whole point of 00:01:45.519 --> 00:01:49.040 the wheel is to create artificial gravity because 00:01:49.439 --> 00:01:52.079 Well, the human body absolutely hates weightlessness. 00:01:52.579 --> 00:01:55.120 It really is. The human body evolved over millions 00:01:55.120 --> 00:01:58.219 of years under a constant 1G downward pull. When 00:01:58.219 --> 00:02:00.260 you're in orbit, you are basically in a state 00:02:00.260 --> 00:02:02.500 of continuous free fall. Right. You experience 00:02:02.500 --> 00:02:05.739 microgravity. Exactly. And without that downward 00:02:05.739 --> 00:02:08.800 pull, everything inside you gets totally confused. 00:02:08.939 --> 00:02:10.919 I mean, the fluids in your body no longer pool 00:02:10.919 --> 00:02:13.479 in your legs. They shift up into your chest and 00:02:13.479 --> 00:02:15.979 your head. Oh, man. Yeah, astronauts often get 00:02:15.979 --> 00:02:18.560 what they call a Puffy face syndrome. Yeah, puffy 00:02:18.560 --> 00:02:21.300 face syndrome. And it's not just cosmetic. The 00:02:21.300 --> 00:02:23.240 increased pressure can actually flatten the back 00:02:23.240 --> 00:02:25.759 of their eyeballs, which causes long -term vision 00:02:25.759 --> 00:02:27.800 problems. Wow, just from the fluid shifting. 00:02:28.000 --> 00:02:31.020 Right. And without the daily stress of gravity, 00:02:31.379 --> 00:02:33.680 your bones actually stop regenerating properly. 00:02:34.039 --> 00:02:37.039 You can lose up to 2 % of your bone mass every 00:02:37.039 --> 00:02:39.810 single month. That is wild. And I guess your 00:02:39.810 --> 00:02:41.490 muscles atrophy, too, right? Because they don't 00:02:41.490 --> 00:02:44.050 have to carry your weight. Exactly. So the proposed 00:02:44.050 --> 00:02:46.889 cure for all this biological chaos is just to 00:02:46.889 --> 00:02:49.629 spin the space station. But to understand the 00:02:49.629 --> 00:02:51.330 mechanics of that, we have to look at the math. 00:02:51.449 --> 00:02:54.710 Right. The physics relies on centrifugal acceleration, 00:02:55.050 --> 00:02:58.129 which is defined by a very specific, somewhat 00:02:58.129 --> 00:03:01.550 intimidating equation, which is a equals negative 00:03:01.550 --> 00:03:04.229 omega squared r. OK, let's break that down. Sure, 00:03:04.710 --> 00:03:07.629 the A represents the linear acceleration you 00:03:07.629 --> 00:03:10.129 feel at the perimeter, so the simulated gravity. 00:03:10.569 --> 00:03:12.689 The omega symbol, that's the angular velocity, 00:03:13.129 --> 00:03:16.210 which simply means how fast the station is spinning. 00:03:16.430 --> 00:03:19.490 Right, the spin speed. Yeah. And the R is the 00:03:19.490 --> 00:03:21.469 radius, the distance from the very center of 00:03:21.469 --> 00:03:24.189 the station out to the outer rim. Okay, now for 00:03:24.189 --> 00:03:26.530 you listening, let me translate that math into 00:03:26.530 --> 00:03:28.930 something a bit more tangible. Think about one 00:03:28.930 --> 00:03:30.909 of those old school salad spinners you might 00:03:30.909 --> 00:03:33.330 have in your kitchen. That's a great way to picture 00:03:33.330 --> 00:03:35.430 it. Right. You wash your lettuce, you put it 00:03:35.430 --> 00:03:37.610 in the basket, and you pump the handle to spin 00:03:37.610 --> 00:03:40.229 it. The lettuce wants to fly off in a straight 00:03:40.229 --> 00:03:43.729 line, but the solid wall of the spinning basket 00:03:43.729 --> 00:03:46.250 gets in the way. Exactly. So the lettuce gets 00:03:46.250 --> 00:03:48.469 pinned against the outer wall while the water 00:03:48.469 --> 00:03:50.930 gets forced out through the slits. Yeah. So in 00:03:50.930 --> 00:03:53.129 a rotating space station, you are the lettuce. 00:03:53.449 --> 00:03:55.590 The floor of the space station is actually the 00:03:55.590 --> 00:03:58.469 inside curve of the outer wall. As the wheel 00:03:58.469 --> 00:04:01.110 spins, the wall is constantly pushing up into 00:04:01.110 --> 00:04:03.629 your feet and pitting you against it. That's 00:04:03.629 --> 00:04:05.729 spot on. And you can dial in whatever gravity 00:04:05.729 --> 00:04:08.030 you want using those two variables, the speed 00:04:08.030 --> 00:04:09.909 of the spin and the size of the wheel. So you 00:04:09.909 --> 00:04:12.370 could simulate Earth gravity, Martian gravity, 00:04:12.530 --> 00:04:15.889 or lunar gravity just by, like, speeding up the 00:04:15.889 --> 00:04:17.750 rotation. Yeah, or by designing a wheel with 00:04:17.750 --> 00:04:20.370 a larger radius. Yeah. But here's the catch. 00:04:20.620 --> 00:04:23.699 The challenge is that the human inner ear is 00:04:23.699 --> 00:04:26.819 incredibly sensitive to rotation. Oh right, the 00:04:26.819 --> 00:04:29.740 inner ear controls our balance. Exactly. If you 00:04:29.740 --> 00:04:32.040 build a really small wheel and spin it super 00:04:32.040 --> 00:04:35.220 fast to get that 1g of gravity, the Coriolis 00:04:35.220 --> 00:04:37.860 force will severely mess with your vestibular 00:04:37.860 --> 00:04:39.620 system. So you'd just be dizzy all the time. 00:04:39.740 --> 00:04:42.060 Oh, it would be awful. Every time an astronaut 00:04:42.060 --> 00:04:44.459 turned their head, they would experience extreme 00:04:44.459 --> 00:04:46.980 motion sickness. So to make it comfortable, you 00:04:46.980 --> 00:04:48.920 really have to increase the radius. Okay, so 00:04:48.920 --> 00:04:52.000 bigger is better. Right. A massive wheel allows 00:04:52.000 --> 00:04:54.800 you to achieve that comfortable 1G acceleration 00:04:54.800 --> 00:04:59.620 with a much slower, gentler rotation rate. Usually 00:04:59.620 --> 00:05:01.939 we're talking around one or two revolutions per 00:05:01.939 --> 00:05:05.459 minute. OK, well, if the math is that straightforward, 00:05:05.579 --> 00:05:08.319 just balancing radius and speed, someone must 00:05:08.319 --> 00:05:10.199 have figured this out way before we were actually 00:05:10.199 --> 00:05:12.600 launching rockets, right? Oh, absolutely. The 00:05:12.600 --> 00:05:15.920 core concept actually dates back to an 1869 science 00:05:15.920 --> 00:05:18.680 fiction story called The Brick Moon, but it transitioned 00:05:18.680 --> 00:05:21.180 from fiction to hard engineering long before 00:05:21.180 --> 00:05:24.180 Sputnik. Okay, so when did the actual scientists 00:05:24.180 --> 00:05:27.899 get involved? Right around 1928 and 1929, an 00:05:27.899 --> 00:05:31.240 engineer named Hermann Pocanek, who also published 00:05:31.240 --> 00:05:33.980 under the pseudonym Hermann Nordung, he produced 00:05:33.980 --> 00:05:36.240 the very first detailed, mathematically sound 00:05:36.240 --> 00:05:38.519 description of a spinning wheel space station. 00:05:38.620 --> 00:05:40.480 Yeah, I was looking at his designs and the source 00:05:40.480 --> 00:05:42.800 material and they are just mind -blowing. They 00:05:42.800 --> 00:05:45.399 really are. His book, The Problem of Space Travel, 00:05:46.040 --> 00:05:48.079 described a wheel station that was 30 meters 00:05:48.079 --> 00:05:50.579 in diameter, which is roughly 100 feet across. 00:05:50.879 --> 00:05:53.959 Pocanek is sitting in Vienna in the 1920s, decades 00:05:53.959 --> 00:05:55.990 before the for a satellite. And he doesn't just 00:05:55.990 --> 00:05:58.089 say, hey, let's put a spinning wheel in space. 00:05:58.430 --> 00:06:01.370 He specifically suggests putting it into a geostationary 00:06:01.370 --> 00:06:04.550 orbit. Right, a massive 22 ,000 miles up where 00:06:04.550 --> 00:06:07.110 the station would stay fixed over one specific 00:06:07.110 --> 00:06:10.230 point on Earth. And even crazier, he designed 00:06:10.230 --> 00:06:13.079 it to run on solar power. I mean, photovoltaic 00:06:13.079 --> 00:06:14.980 solar panels weren't even a thing yet. So he 00:06:14.980 --> 00:06:17.579 designed the station with these giant concave 00:06:17.579 --> 00:06:20.279 mirrors attached to the hub. Yeah, it was incredibly 00:06:20.279 --> 00:06:22.980 ingenious. The mirrors were designed to concentrate 00:06:22.980 --> 00:06:26.060 ambient sunlight onto a series of boiler pipes. 00:06:26.199 --> 00:06:28.639 Oh, so like a steam engine in space. Basically, 00:06:28.819 --> 00:06:32.040 yeah. The intense heat would boil a fluid inside 00:06:32.040 --> 00:06:35.199 the pipes, generating steam or pressurized gas 00:06:35.199 --> 00:06:37.779 to spin a turbine, which would then generate 00:06:37.779 --> 00:06:39.699 electricity for the station. He was designing 00:06:39.699 --> 00:06:42.720 complex thermodynamics solar power plants for 00:06:42.720 --> 00:06:45.839 the vacuum of space before the invention of the 00:06:45.839 --> 00:06:48.259 jet engine. That is insane. He really understood 00:06:48.259 --> 00:06:50.879 the fundamental logistical needs of an isolated 00:06:50.879 --> 00:06:53.879 orbital habitat. You need simulated gravity, 00:06:54.220 --> 00:06:56.459 infinite power, and a stable orbit. And he wasn't 00:06:56.459 --> 00:06:58.319 the only one doing this kind of theoretical groundwork 00:06:58.319 --> 00:07:01.060 either. No, not at all. Konstantin Tsiolkovsky, 00:07:01.120 --> 00:07:03.480 who is a brilliant aerospace visionary in the 00:07:03.480 --> 00:07:07.120 Soviet Union, drew up concepts in 1933 for a 00:07:07.120 --> 00:07:10.019 rotating toroidal ring. Like a donut shape. Exactly, 00:07:10.139 --> 00:07:12.240 donut shape. and his was specifically to serve 00:07:12.240 --> 00:07:15.079 as a greenhouse in space. Wait, a greenhouse? 00:07:15.319 --> 00:07:17.720 Why did it need to spin? Well, he realized that 00:07:17.720 --> 00:07:19.740 if you want to grow food in orbit, plant roots 00:07:19.740 --> 00:07:22.199 need to know which way is down, and that requires 00:07:22.199 --> 00:07:25.879 simulated gravity. That is so smart. But the 00:07:25.879 --> 00:07:27.560 concept that really put this on the map, the 00:07:27.560 --> 00:07:29.259 one that saturated the public consciousness, 00:07:29.879 --> 00:07:32.680 That was Wernher von Braun's design in 1952, 00:07:32.699 --> 00:07:35.339 right? Yes, absolutely. Von Braun and Willy Ley 00:07:35.339 --> 00:07:37.920 wrote a highly influential series of articles 00:07:37.920 --> 00:07:41.319 in Collier's magazine. They took Potinik's mathematical 00:07:41.319 --> 00:07:44.459 foundation and just scaled it up into an absolute 00:07:44.459 --> 00:07:46.800 behemoth. How big are we talking? They proposed 00:07:46.800 --> 00:07:50.060 a massive three -deck wheel that was 76 meters, 00:07:50.379 --> 00:07:53.269 or about 250 feet in diameter. Wow. OK. Yeah, 00:07:53.370 --> 00:07:55.810 and it was intended to revolve at a leisurely 00:07:55.810 --> 00:07:58.509 three rotations per minute, which would provide 00:07:58.509 --> 00:08:01.189 one third of Earth's gravity for a crew of 80 00:08:01.189 --> 00:08:03.189 people. OK, wait. I have to push back on this 00:08:03.189 --> 00:08:06.569 timeline for a second. This is 1952. We hadn't 00:08:06.569 --> 00:08:09.730 put a single dog, monkey, or human into space 00:08:09.730 --> 00:08:12.550 yet. True. How were they planning to lift thousands 00:08:12.550 --> 00:08:16.069 of tons of heavy steel 250 feet across up into 00:08:16.069 --> 00:08:19.139 the vacuum of space? Well, von Braun wasn't proposing 00:08:19.139 --> 00:08:21.879 launching it in one piece. The Collier's articles 00:08:21.879 --> 00:08:24.480 detailed an entire infrastructure architecture. 00:08:24.720 --> 00:08:26.720 Oh, so they had a construction plan. Yeah, he 00:08:26.720 --> 00:08:30.160 envisioned a fleet of massive reusable three 00:08:30.160 --> 00:08:34.159 stage cargo shuttles. They would carry prefabricated 00:08:34.159 --> 00:08:37.580 flexible nylon and plastic sections up into orbit, 00:08:37.740 --> 00:08:40.179 basically flat packed. So like Ikea furniture 00:08:40.179 --> 00:08:42.919 for astronauts. Essentially, yes. Astronauts 00:08:42.919 --> 00:08:45.039 in pressurized suits would then assemble the 00:08:45.039 --> 00:08:48.460 wheel in orbit piece by piece. like a giant orbital 00:08:48.460 --> 00:08:51.000 erector set. That is incredibly ambitious. It 00:08:51.000 --> 00:08:54.159 was. Von Braun saw this station not just as a 00:08:54.159 --> 00:08:57.559 laboratory, but as a mandatory deep space shipyard 00:08:57.559 --> 00:08:59.779 and staging point for an eventual human mission 00:08:59.779 --> 00:09:02.259 to Mars. Wow. What's fascinating here is how 00:09:02.259 --> 00:09:05.120 these early scientists, Potashenko, Tsiolkovsky, 00:09:05.159 --> 00:09:09.039 Von Braun, they accurately anticipated and mathematically 00:09:09.039 --> 00:09:11.960 solved the debilitating biological problems of 00:09:11.960 --> 00:09:15.059 microgravity. decades before a human body ever 00:09:15.059 --> 00:09:17.179 actually experienced them. They preemptively 00:09:17.179 --> 00:09:19.220 engineered the cure for a disease we hadn't even 00:09:19.220 --> 00:09:22.419 caught yet. But it's one thing to draw incredibly 00:09:22.419 --> 00:09:25.200 forward -thinking pictures in a 1950s magazine, 00:09:25.919 --> 00:09:28.820 or solve physics equations in a notebook in 1929. 00:09:29.419 --> 00:09:31.539 Taking those flat sketches and turning them into 00:09:31.539 --> 00:09:34.580 actual physical hardware that has to survive 00:09:34.580 --> 00:09:37.289 the vacuum of space? changes the game entirely. 00:09:37.490 --> 00:09:39.889 It really does. The engineering jump is massive. 00:09:40.070 --> 00:09:42.629 Did any space agency ever actually try to physically 00:09:42.629 --> 00:09:45.950 build one of these wheels? They did. NASA formalized 00:09:45.950 --> 00:09:49.490 their interest in 1959. A special committee actually 00:09:49.490 --> 00:09:52.070 opined that a rotating space station was the 00:09:52.070 --> 00:09:54.669 absolute next logical step after the Mercury 00:09:54.669 --> 00:09:57.509 program. Oh, well. Yeah. By 1960, they began 00:09:57.509 --> 00:09:59.850 physical development and ground testing on something 00:09:59.850 --> 00:10:02.970 called the Erectable Taurus Manned Space Laboratory. 00:10:03.269 --> 00:10:05.809 The Erectable Taurus. OK, that's a mouthful. 00:10:05.809 --> 00:10:07.649 How are they planning to get it up there? The 00:10:07.649 --> 00:10:10.850 plan was to launch this station, fold it up inside 00:10:10.850 --> 00:10:13.309 the nose cone of a Mercury Atlas III rocket. 00:10:13.289 --> 00:10:16.230 Fold it up, wait, like a balloon. Exactly like 00:10:16.230 --> 00:10:18.809 a balloon. Once it reached orbit, it would inflate 00:10:18.809 --> 00:10:21.549 like a massive inner tube to a diameter of 24 00:10:21.549 --> 00:10:23.889 feet, creating that necessary doughnut shape. 00:10:24.090 --> 00:10:26.870 OK, that sounds wild. And then once fully pressurized 00:10:26.870 --> 00:10:29.830 and rigid, small thrusters would spin it up to 00:10:29.830 --> 00:10:32.789 create the artificial gravity. NASA engineers 00:10:32.789 --> 00:10:35.629 actually built two physical prototypes of this 00:10:35.629 --> 00:10:39.470 inflatable torus on the ground in 1964 to simulate 00:10:39.470 --> 00:10:42.210 living and working inside it. OK, I know everyone 00:10:42.210 --> 00:10:44.230 listening is thinking the exact same thing right 00:10:44.230 --> 00:10:46.970 now because this sounds terrifying. An inflatable 00:10:46.970 --> 00:10:50.350 space station in the early 1960s. Yeah, it was 00:10:50.350 --> 00:10:52.470 pretty daring. You're talking about putting human 00:10:52.470 --> 00:10:55.210 beings inside a giant rubber balloon spinning 00:10:55.210 --> 00:10:57.750 it rapidly in the dead vacuum of space while 00:10:57.750 --> 00:11:00.409 surrounded by micro meteoroids and orbital debris. 00:11:00.889 --> 00:11:03.250 What happens if a piece of rock punches a hole 00:11:03.250 --> 00:11:05.580 in it? Right, so the fear of a fatal puncture 00:11:05.580 --> 00:11:07.639 in the inflatable membrane was definitely a major 00:11:07.639 --> 00:11:10.240 concern, but it actually wasn't the only physics 00:11:10.240 --> 00:11:12.559 problem they ran into. Really? What else went 00:11:12.559 --> 00:11:14.919 wrong? The overriding technical reason the project 00:11:14.919 --> 00:11:17.320 was cancelled had to do with mass distribution 00:11:17.320 --> 00:11:19.919 and angular momentum. OK, unpack that for me. 00:11:20.259 --> 00:11:22.799 Well, when you have a hollow, 24 -foot inflatable 00:11:22.799 --> 00:11:25.740 wheel spinning in a frictionless vacuum, its 00:11:25.740 --> 00:11:28.179 stability depends entirely on the center of mass 00:11:28.179 --> 00:11:30.299 remaining perfectly aligned with the axis of 00:11:30.299 --> 00:11:33.590 rotation. Which means, wait... If a couple of 00:11:33.590 --> 00:11:35.269 astronauts float over to the same side of the 00:11:35.269 --> 00:11:37.549 station to look out a window, they change the 00:11:37.549 --> 00:11:40.769 center of mass, don't they? Yes. Exactly. I can 00:11:40.769 --> 00:11:43.049 just imagine the catastrophic wobble. It would 00:11:43.049 --> 00:11:45.110 be like an unbalanced washing machine when you 00:11:45.110 --> 00:11:47.210 put too many heavy towels on one side. That's 00:11:47.210 --> 00:11:49.750 a perfect analogy. But instead of just violently 00:11:49.750 --> 00:11:52.269 shaking in your laundry room, it's doing it in 00:11:52.269 --> 00:11:54.840 space, which could tear the fabric apart. The 00:11:54.840 --> 00:11:57.259 engineering tolerances required to keep a rotating 00:11:57.259 --> 00:12:01.259 structure stable are incredibly tight. Any localized 00:12:01.259 --> 00:12:04.159 variation in mass creates a severe wobble known 00:12:04.159 --> 00:12:06.779 in orbital mechanics as a nutation. A nutation, 00:12:06.779 --> 00:12:09.460 okay. Yeah, and in a rigid structure you can 00:12:09.460 --> 00:12:12.740 counteract that with heavy gyroscopes or by pumping 00:12:12.740 --> 00:12:14.980 water ballast around the ring to rebalance it 00:12:14.980 --> 00:12:17.539 in real time. But in an inflatable station. In 00:12:17.539 --> 00:12:20.879 an inflatable 1960s torus that wobble would not 00:12:20.879 --> 00:12:23.720 only make the crew incredibly sick but could 00:12:23.789 --> 00:12:26.350 easily cause the station to tumble wildly out 00:12:26.350 --> 00:12:30.230 of control or suffer structural failure. So the 00:12:30.230 --> 00:12:33.330 1960s inflatable doughnut gets scrapped because 00:12:33.330 --> 00:12:35.889 of the washing machine effect. Basically, yeah. 00:12:36.149 --> 00:12:38.409 But here's where it gets really interesting. 00:12:39.129 --> 00:12:41.529 We didn't totally give up on the idea. We just 00:12:41.529 --> 00:12:44.409 scaled it down and modernized it to solve that 00:12:44.409 --> 00:12:47.120 exact engineering problem. Let's look at the 00:12:47.120 --> 00:12:50.200 2010s. Ah, yes. NASA starts exploring a project 00:12:50.200 --> 00:12:53.340 called Nautilus X. Right. Nautilus X was a brilliant 00:12:53.340 --> 00:12:56.340 compromise of an idea. By the 2010s, we already 00:12:56.340 --> 00:12:58.600 had the International Space Station, the ISS, 00:12:59.240 --> 00:13:01.419 operating in orbit. Right, which we said is a 00:13:01.419 --> 00:13:03.820 static, non -rotating structure. Exactly. It 00:13:03.820 --> 00:13:07.139 is entirely a microgravity environment. But NASA 00:13:07.139 --> 00:13:09.500 still desperately needed to study artificial 00:13:09.500 --> 00:13:12.379 gravity to prepare for long -duration deep space 00:13:12.379 --> 00:13:14.879 missions to Mars. So how did Nautilus X fit in? 00:13:15.210 --> 00:13:18.450 So the Nautilus X project proposed adding a centrifuge 00:13:18.450 --> 00:13:21.950 demonstrator directly to the existing ISS. It 00:13:21.950 --> 00:13:24.350 was essentially a rotating sleep quarters module 00:13:24.350 --> 00:13:27.149 shaped like a ring attached to a static station. 00:13:27.549 --> 00:13:29.490 Wait, I need to understand the mechanics of this 00:13:29.490 --> 00:13:31.850 because it sounds impossible. If you attach a 00:13:31.850 --> 00:13:34.490 massive spinning wheel to a floating metal tube 00:13:34.490 --> 00:13:36.750 in space, wouldn't the torque of the spinning 00:13:36.750 --> 00:13:39.289 wheel just grab the static station and start 00:13:39.289 --> 00:13:41.289 twisting it in the opposite direction, like a 00:13:41.289 --> 00:13:43.549 drill bit? In a basic mechanical attachment, 00:13:43.769 --> 00:13:47.379 yes, absolutely. Conservation of angular momentum 00:13:47.379 --> 00:13:50.379 dictates that spinning a heavy ring one way will 00:13:50.379 --> 00:13:52.600 induce a counter spin on the rest of the station. 00:13:53.299 --> 00:13:55.639 So how do they plan to fix that? To solve this, 00:13:56.139 --> 00:13:59.019 the Nautilus X design required incredibly complex 00:13:59.019 --> 00:14:01.679 engineering at the attachment point. You would 00:14:01.679 --> 00:14:03.960 need a counter rotating flywheel spinning in 00:14:03.960 --> 00:14:06.399 the opposite direction to cancel out the torque. 00:14:06.519 --> 00:14:08.919 Oh, that makes sense. More importantly, the rotating 00:14:08.919 --> 00:14:10.799 ring would have to be isolated from the rest 00:14:10.799 --> 00:14:13.620 of the station using frictionless magnetic bearings. 00:14:13.879 --> 00:14:17.370 OK. but you still have to somehow get air. power 00:14:17.370 --> 00:14:20.429 and data across that spinning boundary without 00:14:20.429 --> 00:14:22.490 tangling up a bunch of wires, right? Exactly. 00:14:22.549 --> 00:14:24.870 It's a huge challenge. You would need sophisticated 00:14:24.870 --> 00:14:27.350 slip rings for the electrical and data connections 00:14:27.350 --> 00:14:30.730 and highly complex rotary pneumatic seals to 00:14:30.730 --> 00:14:33.409 allow oxygen to flow between the static and rotating 00:14:33.409 --> 00:14:35.750 sections. While maintaining an airtight seal 00:14:35.750 --> 00:14:38.850 against the vacuum of space. Exactly. The genius 00:14:38.850 --> 00:14:41.110 of the Nautilus X proposal was that if they could 00:14:41.110 --> 00:14:43.309 master those seals, it would have allowed astronauts 00:14:43.309 --> 00:14:45.950 to sleep in a partial gravity environment. Right, 00:14:45.970 --> 00:14:48.029 so their bodies would physically recover from 00:14:48.029 --> 00:14:50.330 weightlessness overnight. Without destroying 00:14:50.330 --> 00:14:52.629 the usefulness of the rest of the ISS for zero 00:14:52.629 --> 00:14:54.730 -gravity experiments during the day? Sleeping 00:14:54.730 --> 00:14:57.149 in a magnetic centrifuge attached to a floating 00:14:57.149 --> 00:14:59.769 space station? I mean, it sounds amazing. But 00:14:59.769 --> 00:15:02.669 judging by the current state of the ISS, I'm 00:15:02.669 --> 00:15:04.730 assuming they didn't pull this off either. Unfortunately, 00:15:05.009 --> 00:15:07.590 no. The Nautilus -X project never advanced beyond 00:15:07.590 --> 00:15:10.289 the initial drawings, feasibility studies, and 00:15:10.289 --> 00:15:12.649 proposal stages. Which brings us to the ultimate 00:15:12.649 --> 00:15:15.799 question of this deep dive. If we have had the 00:15:15.799 --> 00:15:17.919 blueprints for a spinning space station since 00:15:17.919 --> 00:15:23.379 1929, and we physically built inflatable prototypes 00:15:23.379 --> 00:15:27.679 in the 1960s, and we engineered modern, attachable 00:15:27.679 --> 00:15:31.360 sleep centrifuges in the 2010s, why is our current 00:15:31.360 --> 00:15:33.799 multi -billion dollar international space station 00:15:33.799 --> 00:15:37.120 just a bunch of static floating tubes? The obstacles 00:15:37.120 --> 00:15:39.399 are formidable, and they fall largely into two 00:15:39.399 --> 00:15:41.820 categories, logistics and purpose. Okay, let's 00:15:41.820 --> 00:15:44.200 start with logistics. On the logistical side, 00:15:44.330 --> 00:15:46.690 Assembling a massive structure is hard enough. 00:15:47.129 --> 00:15:49.269 Assembling a massive structure that must perfectly 00:15:49.269 --> 00:15:52.610 seal in air, withstand a vacuum, and handle the 00:15:52.610 --> 00:15:54.990 immense outward structural stresses of continuous 00:15:54.990 --> 00:15:58.250 rotation is just a monumental engineering challenge. 00:15:58.350 --> 00:16:01.169 Plus the temperature swings in space. Yes. The 00:16:01.169 --> 00:16:03.429 outside of the station is constantly bombarded 00:16:03.429 --> 00:16:06.470 by unshielded sunlight, heating the metal to 00:16:06.470 --> 00:16:09.490 250 degrees Fahrenheit, while the shadowed side 00:16:09.490 --> 00:16:14.549 plunges to negative 250 degrees. Wow. rotating 00:16:14.549 --> 00:16:17.210 hub seal that doesn't warp and leak under those 00:16:17.210 --> 00:16:19.950 extreme temperature swings is historically far 00:16:19.950 --> 00:16:21.929 beyond available government budgets. Wait, let 00:16:21.929 --> 00:16:24.129 me make sure I'm getting this. If artificial 00:16:24.129 --> 00:16:27.169 gravity is the absolute holy grail of keeping 00:16:27.169 --> 00:16:29.389 human beings biologically healthy while living 00:16:29.389 --> 00:16:32.970 in space, are you saying we spent hundreds of 00:16:32.970 --> 00:16:35.350 billions of dollars and decades building the 00:16:35.350 --> 00:16:39.110 ISS without it entirely because of budget constraints 00:16:39.110 --> 00:16:41.889 and tricky seals? Well, no. If we connect this 00:16:41.889 --> 00:16:44.049 to the bigger picture, the microgravity environment 00:16:44.049 --> 00:16:46.370 of the International Space Station is not a failure 00:16:46.370 --> 00:16:48.590 of engineering or a budget shortfall. It's not. 00:16:48.990 --> 00:16:52.289 No, it is a conscious, deliberate feature. NASA 00:16:52.289 --> 00:16:55.070 and its international partners value the ISS 00:16:55.070 --> 00:16:58.330 specifically because it is a zero -gravity laboratory. 00:16:58.629 --> 00:17:01.529 OK, that is a massive plot twist. We didn't feel 00:17:01.529 --> 00:17:03.629 to build the spinning wheel. We chose not to. 00:17:03.950 --> 00:17:07.150 Why is zero gravity so incredibly valuable? Because 00:17:07.150 --> 00:17:09.970 a spinning wheel provides gravity, which is great 00:17:09.970 --> 00:17:12.369 for the astronauts' bones, but terrible for science. 00:17:12.789 --> 00:17:15.769 The entire purpose of the ISS is to conduct experiments 00:17:15.769 --> 00:17:18.190 that are physically impossible on Earth. Like 00:17:18.190 --> 00:17:20.450 what kind of experiments? Consider fluid dynamics. 00:17:21.069 --> 00:17:23.390 On Earth, gravity drives convection heavier, 00:17:23.789 --> 00:17:26.589 colder fluids sink, and lighter, hotter fluids 00:17:26.589 --> 00:17:29.690 rise. This creates swirling currents in liquids 00:17:29.690 --> 00:17:32.549 and gases. Right. Hot air rises, cold air sinks. 00:17:32.609 --> 00:17:35.579 Exactly. In the total absence of gravity on the 00:17:35.579 --> 00:17:38.500 ISS, convection doesn't exist. This allows scientists 00:17:38.500 --> 00:17:41.240 to study pure capillary action and surface tension. 00:17:41.440 --> 00:17:43.500 I read somewhere that this is a huge deal for 00:17:43.500 --> 00:17:45.839 medical research, specifically growing protein 00:17:45.839 --> 00:17:48.400 crystals. Yes, it is arguably the most valuable 00:17:48.400 --> 00:17:50.700 research done on the station. Really? How so? 00:17:50.859 --> 00:17:53.500 When pharmaceutical companies try to grow protein 00:17:53.500 --> 00:17:55.880 crystals on Earth to study disease structures, 00:17:56.480 --> 00:17:58.720 the gravity -driven convection currents cause 00:17:58.720 --> 00:18:01.440 the crystals to grow with microscopic flaws and 00:18:01.440 --> 00:18:04.380 imperfections in their lattice. Oh, because they're 00:18:04.380 --> 00:18:07.309 settling weirdly due to gravity? Precisely. On 00:18:07.309 --> 00:18:10.769 the ISS, without gravity interfering, those same 00:18:10.769 --> 00:18:13.490 protein crystals grow significantly larger and 00:18:13.490 --> 00:18:15.910 perfectly structured. That's amazing. Research 00:18:15.910 --> 00:18:18.789 on the ISS was directly responsible for understanding 00:18:18.789 --> 00:18:21.450 the structure of a key protein used in the cancer 00:18:21.450 --> 00:18:24.450 immunotherapy drug ketruta. If you spin the station 00:18:24.450 --> 00:18:27.329 to create artificial gravity, you actively destroy 00:18:27.329 --> 00:18:29.769 the exact pristine environment the station was 00:18:29.769 --> 00:18:32.839 built to provide. Wow. That completely reframes 00:18:32.839 --> 00:18:35.200 how I look at the ISS. The floating tube isn't 00:18:35.200 --> 00:18:38.079 a compromise, it is the entire point. Exactly. 00:18:38.319 --> 00:18:40.220 But I think that's why there is such a cognitive 00:18:40.220 --> 00:18:43.420 disconnect between what we expect space to look 00:18:43.420 --> 00:18:45.539 like and what it actually looks like. Because 00:18:45.539 --> 00:18:47.519 when we look at our fiction and our pop culture, 00:18:47.980 --> 00:18:49.900 it is totally saturated with rotating wheels. 00:18:50.039 --> 00:18:52.299 It really is. The visual of the spinning wheel 00:18:52.299 --> 00:18:54.900 is a shorthand for human mastery over space. 00:18:55.200 --> 00:18:57.720 It dominates our media. The most famous one is 00:18:57.720 --> 00:19:00.259 obviously Space Station V in the movie 2001, 00:19:00.759 --> 00:19:03.299 A Space Odyssey, which is the iconic waltzing 00:19:03.299 --> 00:19:05.180 station we started the show with. Right, an absolute 00:19:05.180 --> 00:19:08.900 classic. But even in modern movies. The Endurance 00:19:08.900 --> 00:19:11.960 in Interstellar is essentially a fully realized 00:19:11.960 --> 00:19:14.660 version of that Nautilus X design. Yes, it is. 00:19:14.839 --> 00:19:17.259 It's a deep space staging station that rotates 00:19:17.259 --> 00:19:20.039 to provide gravity for the crew during a multi 00:19:20.039 --> 00:19:23.480 -year interplanetary flight. The fiction always 00:19:23.480 --> 00:19:25.859 gives us rotation. Because fiction is almost 00:19:25.859 --> 00:19:28.119 always a story about people trying to live in 00:19:28.119 --> 00:19:31.400 space, not just running fluid dynamic experiments 00:19:31.400 --> 00:19:33.700 in a laboratory. This raises an important question 00:19:33.700 --> 00:19:35.559 about the fundamental difference between our 00:19:35.559 --> 00:19:38.180 current reality and our future ambitions. What 00:19:38.180 --> 00:19:41.359 do you mean? There is a sharp distinction between 00:19:41.359 --> 00:19:44.119 visiting space to do scientific research, which 00:19:44.119 --> 00:19:46.680 requires a zero gravity environment, and living 00:19:46.680 --> 00:19:48.920 in space permanently, which demands artificial 00:19:48.920 --> 00:19:51.960 gravity for long -term health. So far humanity 00:19:51.960 --> 00:19:54.299 has only been visiting space. So what does this 00:19:54.299 --> 00:19:56.400 all mean for you and me? Let's summarize what 00:19:56.400 --> 00:19:58.539 we've discovered in this deep dive. The rotating 00:19:58.539 --> 00:20:01.299 wheel space station is a brilliant 19th century 00:20:01.299 --> 00:20:04.279 concept that was mathematically and logically 00:20:04.279 --> 00:20:07.460 perfected by early 20th century physicists like 00:20:07.460 --> 00:20:11.220 Herman Botonic and Wernher von Braun. They realized 00:20:11.220 --> 00:20:13.180 the human body would break down without gravity 00:20:13.180 --> 00:20:15.839 long before anyone ever flew. Right. But the 00:20:15.839 --> 00:20:18.380 dream was stalled. by the harsh realities of 00:20:18.380 --> 00:20:20.599 mass distribution, the engineering nightmare 00:20:20.599 --> 00:20:23.559 of rotating airtight seals in a vacuum, and most 00:20:23.559 --> 00:20:26.160 importantly, our current orbital priorities. 00:20:26.880 --> 00:20:29.720 We deliberately sidelined the comfortable gravity 00:20:29.720 --> 00:20:32.319 -simulating space city in favor of the floating 00:20:32.319 --> 00:20:34.940 zero -gravity laboratory because the science 00:20:34.940 --> 00:20:37.400 of weightlessness is simply too valuable to give 00:20:37.400 --> 00:20:39.160 up. We traded the spinning reel for the floating 00:20:39.160 --> 00:20:41.880 laboratory because right now scientific research 00:20:41.880 --> 00:20:44.099 dictates the architecture. But the landscape 00:20:44.099 --> 00:20:46.259 of spaceflight is changing rapidly. Whoa, definitely. 00:20:46.420 --> 00:20:48.680 What happens when government agencies whose primary 00:20:48.680 --> 00:20:51.299 mandate is science are no longer the only players 00:20:51.299 --> 00:20:53.640 in low Earth orbit? What happens when the private 00:20:53.640 --> 00:20:56.519 sector fully takes over? Oh, wow. You're talking 00:20:56.519 --> 00:20:58.539 about commercial space stations and space tourism. 00:20:58.750 --> 00:21:02.210 Absolutely. When your main customers are incredibly 00:21:02.210 --> 00:21:06.190 wealthy space tourists, the priorities flip completely. 00:21:06.329 --> 00:21:09.029 That's true. A space tourist doesn't care about 00:21:09.029 --> 00:21:11.789 fluid dynamics experiments or growing flawless 00:21:11.789 --> 00:21:14.690 protein crystals. They want a comfortable vacation. 00:21:14.869 --> 00:21:16.470 Right. They want to be able to sleep in a normal 00:21:16.470 --> 00:21:19.150 bed without strapping themselves to a wall. Exactly. 00:21:19.549 --> 00:21:22.950 They want to eat a luxury dinner off a plate 00:21:22.950 --> 00:21:26.759 without their peas floating away. And most importantly, 00:21:27.039 --> 00:21:29.380 they do not want to spend their millions of dollars 00:21:29.380 --> 00:21:32.920 severely nauseous from vestibular confusion and 00:21:32.920 --> 00:21:35.359 space adaptation syndrome. No one wants to be 00:21:35.359 --> 00:21:37.279 sick on a million dollar vacation. Exactly. They 00:21:37.279 --> 00:21:39.900 will demand gravity. The market will demand rotation. 00:21:40.140 --> 00:21:42.500 We didn't build the spinning wheel because scientists 00:21:42.500 --> 00:21:45.420 wanted to study zero gravity, but as commercial 00:21:45.420 --> 00:21:47.980 spaceflight companies look to build orbital habitats 00:21:47.980 --> 00:21:51.019 in the 2030s and beyond, the demands of the consumer 00:21:51.019 --> 00:21:53.980 market will heavily incentivize engineers to 00:21:53.980 --> 00:21:57.019 finally overcome those hurdles with rotary seals 00:21:57.019 --> 00:21:59.339 and mass distribution. So it's basically a financial 00:21:59.339 --> 00:22:02.309 incentive now. It is highly likely that capitalism, 00:22:02.630 --> 00:22:05.390 rather than scientific exploration, will be the 00:22:05.390 --> 00:22:07.430 force that finally builds the spinning space 00:22:07.430 --> 00:22:09.849 hotel we've been dreaming of for over a century. 00:22:10.569 --> 00:22:13.869 The first true rotating wheel station won't be 00:22:13.869 --> 00:22:16.210 a government laboratory, it will be a luxury 00:22:16.210 --> 00:22:18.950 resort. That is an amazing thought to leave on. 00:22:19.210 --> 00:22:21.690 The idea that after a hundred years of intense 00:22:21.690 --> 00:22:24.329 physics, mathematical foresight, and canceled 00:22:24.329 --> 00:22:27.309 NASA prototypes, it might be the tourism industry 00:22:27.309 --> 00:22:29.690 that finally puts that giant wheel in orbit. 00:22:29.819 --> 00:22:31.619 It's pretty poetic when you think about it. It 00:22:31.619 --> 00:22:34.140 really is. So the next time you see that gleaning, 00:22:34.319 --> 00:22:37.160 wheel -shaped space station waltzing to classical 00:22:37.160 --> 00:22:40.220 music on a movie screen, just remember, the math 00:22:40.220 --> 00:22:42.839 is real, the blueprints are waiting, and its 00:22:42.839 --> 00:22:45.039 actual arrival might just be waiting on the right 00:22:45.039 --> 00:22:45.640 paying customer.