I remember 3 decades ago, when I was in Mechanical Engineer Polytechnic School, I got interested in rotating space stations (ring type) and worked out all the math formulas for stress on the shell depending on rotation speed and diameter and materials used (tensile strength and density and useful cargo on top). I found a NASA white paper and I had done it all right, I was so proud. I even found a small typo on their paper and emailed the authors. Back then Internet was so small, they actually replied >.
I imagine you found the same paper I found when I was trying to figure out what was the smallest a ring space station could be to make inhabitants comfortable with low G and not throw up their lunch due to spin. I was doing this for a (hopefully) hard sci-fi story I was writing. My best determination was (I believe--it was a few years back) 50m diameter, a spin somewhere around 3RPM with a G close to between the Moon and Mars. I doubt the helpful sites I found back in 2008 are still there.
@OverviewEffekt interestingly, the math for rotating habitats is the same as a suspension bridge! The length of the bridge is the circumference of the habitat, and the stresses on it is the same as whatever material it's made out of under the same gravity that you're spinning it up to. I could be slightly incorrect or explained it poorly, but it's quite simple and mundane!
Gravity plating with condensed material in micrometer strings held by electron degeneracy pressure from collapsing into black hole.....or something more even technical.
1989. I was in college (undergrad) and joined the Traveller Mailing List. That's a sci-fi pen and paper RPG. The list started a group adventure about visiting a newly discovered ringworld, and I got put on the team to make content for the ringworld (yeah, three of us tasked to make 3 million Earths of content). I'd gotten my hands on some 3D rendering software (we won't mention how), and tried making renders of what it would be like to actually see the ringworld, complete with fractal land, ocean, clouds. Remember, this was 1989. My poor little 80386 PC (with no math coprocessor) took 18-22 hours to render a single 640x480 resolution image. This was all running under DOS - no multitasking. Meaning my computer was completely occupied and unusable while it was rendering. Another guy on the list tried using his work computer (a Sun Sparc I think) and it completed the render in 17 minutes. Those two factors made me give up after rendering just a few images. It's nice to see the same thing rendered with modern hardware. Thanks for the trip down memory lane.
3D app, late 80's, 386, no co-pro so 386-SX, probs 25MHz clock.... maybe 33MHz.... Real early Lightwave? I used POV-Ray and the modeler Moray back in '93 on a DX5-133, and a basic dive to the planet surface animation at 320x240 at 12fps took a couple of weeks to render, when my parents didn't turn the PC off at the power switch while I was in class.... Your pain is well understood. :)
Even this was hard to render on modern hardware, though not that bad. About an hour per frame on on average on my GTX 1080 and had to use the (wonderful!) free render farm sheepit. It’s really the glossy floor that makes it hard. I had to use some tricks to minimize the light bounces in the floor. And had to render it multiple times to get all of the glitches out. I made the Ringworlds procedurally using blender's geometry nodes (which I’m addicted to) and it was actually pretty fun to do it that way. It could have been much better, but it’s always a time/quality equation you have to balance.
When I think spin gravity, my first thought is always the coriolis stations from Elite. It's where I learned the concept, and the ring stations from Elite Dangerous are the perfect mix of realistic functionality and far future technology.
For many people, the cylinder space stations from the Gundam series are iconic and a very important plot point in the series. Thank you for adding Babylon 5!
Yeah quite the oversight to not include Gundam. The designs were ripped direct from Gerard K. O'neill's work which is the seminal documentation on spin gravity space colonies.
Even in the Halo books they call out the fact that the Halos dont seem to operate on spin gravity, and the first Halo book was actually fairly hard scifi. Verbatim they say "the numbers dont check out". As for why its a ring? Every gun needs a barrel.
@Unethical.FandubsGames I would but it's been spoiled at least a dozen times in the comments already and it's been a quarter of a century. I'd say the cat's kind of out of the bag, don't you think?
Agreed. There's data from the books and source material (Like how the Expanse books provide detail on how Ceres was spun up, the TV series gets it wrong) that isn't shown here. Likely due to time constraints.
It is terribly inefficient to build such megastructures. All these sci-fi novels, films, series and the like are just spreading bullshit. It would be better to just inhabit a planet instead of these La La Land structures. It's always about gravity, but never about the fact that you can't just recreate an entire ecosystem without making compromises. At some point these wannabe planets would collapse because of their problems. Having to find a technical solution for every problem only makes things worse. More technology, more potential sources of error, etc... These things are rotating death traps.
You explained everything pretty well. One aspect you kind of overlooked is WHY someone would get nauseous on a smaller spinning hub like the 2001 example. The film shows Dave Bowman jogging inside. If he wanted an easy jog, he would jog anti-spinward. If he wanted a rigorous jog, he would run spinward. His ~10 feet per second added to the hub's angular velocity would increase his 'weight' noticeably. Also, just standing up from laying in bed. The inner ear would experience a noticeable centripetal acceleration change. And as mentioned about Bowman, moving spinward OR anti spinward would also wildly change the inner ear's acceleration.
@@Akio-fy7ep Moving spinward, antispinward, radially in and out. . .all would effect the inner ear noticeably inside a small diameter hub. It would be like being aboard a smaller ship in rough seas. *One big difference in a hub* YOUR movement controls the acceleration fluctuations in a hub by moving in ANY direction as opposed to the sea controlling the acceleration change on a ship. NOT controlling random accelerations is MUCH more nauseating. So yes, I agree. I imagine it would be moderatly easier to get over the "seasickness" on a hub with a smaller radius. As is said in the video, once the radius gets to around 80 meters and the spin speed provides around 0.5g, the changes in accelerations by your movement become too small to notice unless your on a vehicle riding the hub's inner surface.
I imagine that on a long enough timeframe at least some humans probably have the capacity to get used to the patterns and live problem-free long-term even at high-RPM. Probably they'd even get a sense for which way is spinward, from the tiny constant movements and the slight forces the spin would cause.
Yeah, I totally glossed over the Coriolis effect to focus on the other factors. Also some astronauts are legends made out of unobtainium and could handle anything. Probably Dave was made of this stuff.
If I remember correctly (big IF) Larry Niven's Ringworld was made out of a material called "Skrith". A physicist calculated that skrith had to have a tensile strength on par with the strong nuclear force to avoid being ripped apart by centrifugal forces. Great books, loved the video.
'Scrith', actually. Niven solved the lack of dynamic stability in the Ringworld by having the Pak builders put Bussard ramjets around the circumference, controlled to return the ring to its 'proper' position when it drifted out of place. The City Builders jerked the Ringworld over, once they found a way to cross through the ring walls, by dismounting the stabilizing ramjets to convert them into starships; after enough of the stabilizing ramjets had been removed, the Ringworld began to drift, to the point that it became necessary to fire the Ringworld's defense mechanism (a system mounted on the shadow squares to induce the star to eject a bolt of plasma) against the Ringworld's surface to push it back into line.
@@seanmalloy7249 That wasn't his point at all. He wasn't saying anything about the stability of the Ringworld (which was covered in the video) but the tensile strength of the structure so that it didn't break apart.
Great study! A follow-up study could be a survey of scifi novels about Dyson spheres. And perhaps another one about black holes, bubble universes, worm holes, multiverses, etc.
4:31 what's interesting about the Elysium space station is that its torus is open on the inside, and the atmosphere is just held in there using centripetal forces. I did an estimation on that during my school time, and there is no way it can hold sufficient atmosphere at that size. Would need to be a lot higher g-force so people in the station don't suffucate, but such high forces would be too crushing.
They may have gotten the idea from Ringworld, but that structure has very high walls on the edges - hundreds of miles at least. (The book gives details, but it’s been decades since I read it.)
Exactly. It becomes obvious when you realise that the only reason we have over 100 kPa of pressure here on Earth's surface is that that there's a column of 10 metric tons of air above each square meter of surface, compressing itself with its weight more and more as you go deeper into the atmosphere. And that column is like 100 km deep here, more than the station's diameter.
It is terribly inefficient to build such megastructures. All these sci-fi novels, films, series and the like are just spreading bullshit. It would be better to just inhabit a planet instead of these La La Land structures. It's always about gravity, but never about the fact that you can't just recreate an entire ecosystem without making compromises. At some point these wannabe planets would collapse because of their problems. Having to find a technical solution for every problem only makes things worse. More technology, more potential sources of error, etc... These things are rotating death traps.
Also 12 disciples, 12 tribes of Israel, 12 crew of the original Lazarus missions. Lots of religious callbacks in the story. The time parallel is very fitting though.
Gravity has never been proven; Never been detected, Never been observed. You need to prove against all other rationale that the reason an object drops is uniquely the act of gravity and nothing else. -You have to prove how all matter attracts all other matter indefinitely, and how that concept is why things fall. Helium balloons disprove gravity. Bumble bees disprove gravity - Their wings can't support their body weight. Gravity is a scape goat for all things that cant be explained
Halo is a ring because it's a weapon first, and a sanctuary second. It builds up energy in the middle of the ring for a while before firing, sending more energy into the accumulated mass from points all around the circumference. IRL wise, it looks cool, of course, but that's the in-lore explanation
It also has the advantage of being able to, basically, hit itself. Seeing as the point of this weapon was to wipe out all organic life (above a certain level) in it's entire operating area, by making it a ring with the land facing inward it also hits it's own environment when fired. The other reason for being a ring is likely because this shape means it will be the least in it's own way when that ball of death it builds up in the middle goes off. No clue why it spins though.
@Amanoob105 Spinning makes it easier to stabilize. It's easier to maintain a constant spin than to stay perfectly still. It also causes day and night cycles for the ecosystems on the Ring, as seen in the original game
All strong, Excession was an absolute banger, Look to Windward got me in the feels. Working my way through Matter now and the eons old shell world concept has been blowing my mind
I just found your channel and ive been slowly going through your videos. Struggles at work kinda dimmed my enthusiasm for engineering but watching your videos gives me new energy and drive to get back into big projects! Thank you for the amazing job you do!
For anyone who hasn't read it, Project Hail Mary is excellent. I was a bit skeptical of it going in, but it ended up being my favorite of Andy Weir's novels.
They are making a movie out of it starring Ryan Gosling. I really want to see how they portray rocky. I hope a combination of excellent puppets and CGI
My favorite are the orbitals. A lot of sci-fi structures that big feel like they're going for the wow factor, but in the context of The Culture, the orbitals just seem like the most logical construction for a post-scarcity society that needs homes for trillions of beings. The fact that those people get to design the landscapes and live on big luxurious parcels of land if they want to just adds to the advanced future vibe. All of these were great picks to include in this list -- great video!
@@adsilcott I also like that they generally *don't* live on planets - iiirc it's because the prevailing attitude is that planets should be left for species to naturally evolve upon,and more advanced species should leave them alone.
@@tappajaav if it's a matter of building a habitat vs terraforming a planet, then yeah the former is much more efficient. I like Isaac Arthur's analogy. Terraforming a planet is like hollowing out a big tree to make one tiny home, whereas building space habitats is like cutting down that same tree and using the lumber to make a much bigger house.
@@adamlytle2615 That's correct. They also enjoy the flexibility of artificial platforms, and bypassing the territorial fighting that planetary estate often comes up with
Oh hey, the exact comment I was about to make! But yes, those are interesting because they actually have distinct rotational periods from eachother, and all their stats are listed on the wiki. Also Orbis class starports can have two different sizes of habitat rings spinning at the same rate, meaning they'd have different internal gravity. (I say "can" because they're modular and not every Orbis has both or even any types of habitat rings.) Elite: Dangerous does also commit the physics sin of spun-up asteroid bases, but natural asteroids in the game already spin unrealistically quickly, so I might give it a pass. :P
I get so excited when someone mentions B5. It’s been 30 years, but the show still gets so little love. Thank you for doing this! The Agamemnon from B5 is a pretty cool example, BTW. It’s Captain Sheridan’s old ship, about a mile long, with a large revolving section to simulate gravity, but rather than be a wheel like we commonly see, it’s basically two pie slices connected at the center, similar to the Leonov from 2010. Oh, yeah, and the Leonov is kinda cool, too, I guess (Forgot about it until the Agamemnon reminded me). Not saying you should do another video on the subject, I just thought I’d mention it. Again: Thank you for doing this!
@ i always rewatch it a little different if I can. One year I rewatched it with the movies in their proper places (Which is rough because Thirdspace takes place *inside* a regular episode) Another time I watched it, I stopped at “Objects at Rest,” then watched River of Souls, Rangers, call to Arms, Crusade, lost Tales, and THEN Sleeping in Light. This last time through I just skipped Season 5 entirely, and just jumped from “Rising Star” to “Sleeping in Light.” Each time it’s caused SiL to have a different emotional impact on me.
What thought went through my mind is that when you're speaking of these truly huge structures, could you not achieve gravity rather than by spin, by thickness of the ring? It's not Earth's spin that gives us 1g, it's her mass underneath us.
Another thing to consider: How about a ring that is spinning more slowly (only for stability, perhaps), but closer to a sun -- so close that the actual gravity of the sun is pulling on it with the force of 1gravity? The math would be the same as for Ringworld, but the living space would be on the outer surface with mirrored lighting instead of potentially dangerous additional moving parts. There would still need to be something like the ramjets to nudge it in place but the bridge analogy Niven used for construction and strength still applies. 🤔
First time we encounter Halo in Halo CE, we see it with a PLANET in the background. Rampant gigantomania was added later, likely another fault of allowing novel authors to parasite on your IP.
Another "space station" that would've been awesome to mention is the City from "Blame!", written by Tsutomu Nihei. Basically, the City is a spherical station that can expand itself, and because of plot reasons, the AI building the city started to continuously expand it without ever stopping. This leads to the "station" being just as big as Jupiter's orbit. In fact, at some point the protagonist enters a "room" big enough to encase Jupiter itself, suggesting the planet was entirely harvested. The whole size of the station is unknown, but it is at the minimum 9.6 billion kilometers in diameter.
Yeah, I think there are also a few mechs in anime that are colossal, and bigger than some of our planets. Can't remember which ones, but there was a breakdown of them somewhere.
The Bobiverse you’re such a great series and I wish more people would knew about it. I’m glad you brought it up. You’re the first person I’ve ever heard talk about it or mention it.
Ceres would 100% definitely disintegrate if it was spun up like that. Even solid rock behaves almost like a liquid on planetary scales, thanks to the square-cube law.
In the books I believe they covered the dwarf planet in some structure. I might be confusing that with the space dock that was located at the pole though.
You can 'easily' submerge a train track some miles under the surface, and suspend an endless train right under the surface. The train runs on a maglev suspension on its uhm "ceiling" ? This easily creates gravity. I am pretty certain the solar system can be colonized with "embedded" cylinders, little spinning like centrifuges. Angle them a little, so their conical shape compensates for the gravity of the asteroid or moon. In fact you can 'easily' replicate Earth's surface on the moon by constructing endless such embedded cylinders below the surface. Make em as big as a typical O'Neil cylinder (I built one together with Simon Deering in 2010 for Transvision conference) and you can have about 50% of Earth's surface - but with garden/eden level of comforts - so easily a hundred billion people.
Literally applying the same metric for Ceres, a dwarf planet like Ceres could have a population of, assuming one "layer" of habitats "only" (....) literally One Earth - about 8 billion people, living with a population level and relative spacing of The Netherlands. Now if we were to start stacking the rotational habitats, plus a solidly reinforced structural envelope or "casing" on top of one another, say four layers deep, (some 20 kilometers on the moon) we can have hundreds of billions of people living on the moon. But at that scale the heat emitted by each habitat with all the BBQ's and swedish sauna's and such would become a problem. If we build habitats all over the moon, 4 levels deep, and we assume several times USA levels of heat consumption, the waste heat could make the surface glow on the dark side in infrared at over 100 degrees Celsius.
My head canon is that it's not the whole dwarf planet that is spun up but underground centrifuges that is used to add to the natural gravity rather than trying to completely cancel it and reverse it as spinning the whole planet would need to do.
@@dexterford8094 I remember hearing something about that recently. I hope they get it right. I've been telling people for years that it would make a great movie or TV series. I think a TV series would be the way to go. Especially when it comes to The Garden of Rama. There's just way too much to fit into a movie. A movie for Rendezvous with Rama would work if it was used as an introduction for a TV series that covers from Rama II onward. They could easily get 8-10 seasons out of it.
Actually the Hail Mary spins at about 3.45 rpm. The radius of the centrifuge isn't just half the length of the fully-cable-extended ship. The bulk of the ship's mass is in the non-crew compartment, making the center of mass much closer to that than the crew compartment. The radius of the centrifuge is 75m, making the diameter 150m.
Kudos for making a super interesting video on a subject close to my heart. You touch on the angular velocity limitation of five or six RPM, but also the small size of Discovery means the crew feels significantly lighter at the head than the feet, not a comfortable feeling at all. The Coriolis effect would be wicked, too. Imagine playing centrifugal ping pong!
Oh thank you so much! I left Bobiverse on the second book. If only I had known this would be coming later. I loved this size comparison. The graphics here are _chef’s kiss_. Great job altogether.
9:21 I met Larry Niven once, and he told me that someone had made a scale model of the ring world at a convention he went to. crepe paper was used for the ring because it was the only thing cheap enough to make that massive of a circle lol. Also, Larry is one of the nicest guys you will ever meet. i had no idea he was even an author and i wasn't familiar with his books. He gave me a copy of his most recent book at the time after i talked to him for a bit
7:21 So glad to see The Culture getting some love. Some people daydream about living in Middle Earth or the Old Republic or what have you. I daydream about living on Masaq Orbital.
@@agonefire I never got the 'pet' vibe from all the books. More like 'we like other sentient things around, and we'll try and keep everything ticking over while everybody (including us) does their thing' from the AI's. Yes, it's technically a 'benign dictatorship' I suppose, but with god-like AI's that like having you around, it could be a lot worse?
I mean saying it's not a space station because it's a super weapon is like saying the Death Star isn't a station. It's very much a station, an Arc Ship, and a bunch of other stuff because it's a weapon, but it's primary purpose is to eradicate sentient life. The shape specifically facilitates the firing of the Instillations.
It wasn’t long ago where a comment made a day after you made a vid wouldn’t be buried at the bottom of 800 comments. Very nice work friend. Love that you got the Bobiverse in there at the end. ✌️
When you mentioned the potential to get dizzy, I was surprised you didn't go into some of the weirder aspects of gravity via rotating cylinder: from the perspective of someone on the "ground" -- part of the rotating reference frame, as opposed to an observer watching the ring rotate from outside -- ballistic trajectories aren't the same as in a mass-induced gravity field. The smaller the ring diameter, the more noticeable the deviance from "normal" gravity.
Ixion is a strategy game from a while ago, it featured The Tiqqun (pronounced: "tycoon"), it was a fun spinning space station! Also the OST for that one was amazing!
There are the Iconian Dyson Spheres from Star Trek The Next Generation, we even get to see the Inside of 3 In Star Trek Online, The original Jenolan, the Solanae and the Herald Spheres. Star Trek also has Yorktown Station which also has a ton of handwavium involved but it is an interesting design with how it uses all of space with the artificial gravity letting people live on the different sides of those tunnels in it.
Yorktown Station was just absurd for something that was made before the time of the Original Series. I don't care if it's the alternate timeline, that thing was too advanced even for the ST: Picard setting.
Yorktown Station was far too advanced for human technology in Star Trek and is a good example of how the creators of the movie completely failed at world building
@@RocketToTheMoose The Dyson sphere’s creators never came up in the show. The online game tends to make the fictional world smaller, more trivia-mongering and less imaginative, so the idea of the entirely separate Iconians making the sphere might come from there.
8:24 the Orbitals are angle so as to *not* cast a shadow on themselves. The angle allows the part of the inner surface facing the sun to recieve sunlight without it being blocked by the part of the inner surface facing away, which receives no light
The Gaea trilogy by John Varley deserves a mention. Titan,WIzard, Demon are the book's names. Humanity finds a fairly stealthy artificial satellite in orbit around Saturn. A crewed mission is sent to Saturn, and detects an artificial but LIVING Stanford torus, 1200 kilometers in diameter. It has an artificially dark surface ( vanta black before that was a thing ), and they can't really get any information from it, they theorise ( correctly ) that it is deliberately covert. As they approach they detect that it has extremely low mass, so is obviously hollow. It is under spin, and as they pass by to measure its mass distribution, it exudes tentacles like a cuttlefish, and gathers in the earth-ship. Hy-jinks ensue. Turns out to be an extremely old genetically engineered INTELLIGENT artifact, part of some civilisations' attempt to colonise the Galaxy. And they are successful, the Gaea the ship encounters is one of thousands in our solar system, and it is in contact with a countless community of others spread out across the galaxy. The Gaea's arrive in a solar system as a seed, if they land on resources, they slowly grow up to size by much the same methods as a tree. In the process they eat up the planetoid they have landed on. When they are fully loaded with the amount of resources they will need to thrive, they put themselves into orbit somewhere that they have a energy source, they do not need much. They ensure that their reaction mass ( the parts of their landing body that they don't need ) is launched at a tangent from their circumference, to give themself spin. During this phase, they are compact. When they have made their orbit, they begin to inflate, melting the frozen gases they have gathered. They also grow and launch countless seeds, aimed extra-solar, again from their circumference to spin themselves up. Inside they have complete and detailed control of the ecosystem that lives in the shell of the living world. And they have near miraculous genetic libraries and genetic engineering ability, and listening to Her "Sisters" among the stars, the Gaea can grow a vast library of creatures, from virus size up to whales.
Gaea Trilogy mentioned! I was at university when those books were new, and they were some of my favourites. One of my friends even went so far as to make a homebrew RPG with a Gaean setting.
Those are good books, but seem mostly forgotten. John Varley's earlier writings are incredible, but sometime between this trilogy and “Steel Beach” he came down with a chronic case of the Heinleins and it really ruined his later work. (The same disease cut Spider Robinson's career very short. At least Heinlein himself got a solid 30 years of writing done before succumbing to his namesake syndrome.)
@@mooseyard What is this stupidity you are claiming, in nothing more than parrot fashion. I don't expect you can answer, with clear concise logic and proof. You are running your mouth, in envy, of course.
Very cool video! If I remember correctly, Ceres in the Expanse has been heavily mined and its diameter was divided by two, its only 400km when the first book takes place. Also it's mentionned somewhere that the surface got glassed or melted by the Tycho engineers to help prevent the disintegration under spin forces. Thanks you for a very cool illustration of ringworlds
Glad I waited to comment and bring in the bobaverse when you already addressed it. Thank you for the representation, I dont have a great imagination when it came to that structure.
Arthur C Clarke's books are highly recommendable. You just get sucked into these books, and his ability to describe something extremely complicated in very easily understood language, is amazing. The Rama series is a good place to start. Remember to eat, drink and sleep now and then as you just can't put his books down ! 🙂
There is also Outer Wilds with the Echoes of the Eye DLC. There the stranger is a spinning Space station. It's about 500m in diameter. As well as Stellaris, where you could find and build a Ring around a planet or even around a whole star.
I found it so cool when I managed to get into the center and it was actually a 0g areas. The attention to detail is so impressive, especially because you have to piece everything together without any written history. I loved how they used heaters to make the still water warmer than the rest of the river, for example.
Stellaris really isn't a good example, since we get absolutely no specifications on any of the megastructures. Additionally Orbital Rings are a different beast to Ringworlds.
Gets even more fun if you use Gigastructural Engineering for Stellaris. A singular ring world? Weak sauce! Put four in the same system. Going further? Alderson Disk. No limit? Birch World.
Thistledown in Greg Bear’s Eon would be interesting to see in your fantastic video treatment. Even though the humans in that universe are advanced enough to alter universal constants, the infinite length of The Way would be a fascinating analysis. Keep up the great work!
Greg Bear wrote _Hull Zero Three_ which had an interstellar colony ship where each of the three hulls rotated for gravity. Or would do, if the ship weren't buggered.
I co-authored the first story bible for Halo and was a writer on Halo: Combat Evolved. I specifically wrote the bible's specs for the Halo ring, so I can tell you the bible indicated the ring spins fast enough to provide almost Earth-normal gravity (approximately .93 that of Earth). The caveat about ancient tech "gravity wells" in the ring was added to the write-up to cover any scientific discrepancies that might arise later, so we could say the "gravity tech" made up the difference. But the ring was intended to generate most of its gravity from spin. This may have been contradicted later (I left the franchise in 2003), but I did think about it and write it down at the very start (before the game was even released). Really enjoyed your walk through of the various incarnations of this concept!
The reason for the "spiral tunnels" on Ceres, is that the centrifugal force is being used *additively* to the gravitational force, not subtractively the way you depicted it. This creates increased perceived gravity along a cone shaped surface into the interior of the mass with the poles of rotation at the center of the cone and the point towards the center of the mass. Those tunnels are built along that conical surface. You could also live on the cone at the other pole with the same perceived gravity. The part that's unrealistic, is that the cone should be much more shallow, since it's only a mild increase in gravity. Also, Ceres is definitely not a "rubble pile" asteroid. It's surface is well studied and photographed up close at this point. It is quite solid.
@@CODENAMEDERPY No, the whole thing is spun up, but when you calculate the combined effect of the spin with Ceres' own gravity, the ideal place to build tunnels to utilize the gravity is along the surfaces of those cones, which are mathematical illustrations and not physical structures.
"is that the centrifugal force is being used additively to the gravitational force" Nope. There is no surface where the gravitational and inertial (centrifugal) forces would add up positively. Way worse once you notice that the proposed force due to rotation is the same as surface gravity: It means that the regions furthest from the rotational axis of the planet are no longer bound by gravity and the whole thing would rip it self apart. Gravity always is an inward-vector, centrifugal inertia is always outward. The best you can do to "increase" gravity is to STOP all rotation - for earth that would make a person on the equator about 0.3% heavier - negligible.
The arrows are indicating the centrifugal force, not centripetal. Which might be a little confusing, but I thought it made the point clearer. It all varies on how big the tunnels actually are, and therefore how much centripetal falloff there is both laterally and towards the core. Either way, a tunnel circumnavigating the asteroid, like the Neom The Line city concept, would be ideal. Unless the tunnels are so small that the lateral falloff of acceleration in a cone shape is negligible.
The Gaia Trilogy by John Varley (books: Titan, Wizard and Demon) takes place in a Sanford torus that's an actual sentient entity. It's an extremely fun and bizarre trilogy that's hard to characterize.
I read Titan. It was an interesting, imaginative and fun read! There are two more books? I read Titan so long ago, I'll have to get my hands on all three. When I have leisure time...
@@DrunkenUFOPilot The three books (Titan, Wizard and Demon) all have different tones and get progressively more bizarre, but in a way that makes sense within the broader story. Demon is as tonally different from the first book as it can get and won’t make sense without the second book (Wizard). Demon is crazy insane- in the best way. While none of these are my favorite Sci Fi novels, The Gaea Trilogy as a whole, is easily my favorite Sci Fi trilogy.
There's some way crazier stuff outside Science Fiction, in the realm of speculation, hypotheticals, and pure world-building. Isaac Arthur on TH-cam has some fantastic videos on the subject, and you can find all kinds of blogs and wikis that go over some crazier ideas with viability ranging from fantastical to clever and actually reasonable.
@@AlbertaGeek I could do without his incessant needs to claim CO2 is a 'control mechanism' of temperature. It sure fvckng isn't. ALL records have shown temp proceeds CO2- temp up CO2 then goes up, and the reverse as well. Don't even need to have a thermodynamic background (which basically not ONE person pushing the CO2 bllsht has, and computer models are not field observations) to prove this. Walk into the fvckng shade! LMAO 20-25f drop in temperature IMMEDIATELY.
Sides/Colonies from UC and AC Gundam (Mobile Suit Gundam and Gundam Wing, respectively). I wouldn't know where to start with scaling, but it would be awesome to see in perspective. Awesome vid!
* contingent sigh* I had a really hard day... And this video just made me so happy. Just... Happy. Content. You have a gift, and thank you for exercising it! Please continue!! 💗💗💗💗💗
Where are the O'Neill cylinders, like from Gundam? I figured those would be pretty big? If it's too realistic, it's also used in many of the Gundam Series, so it's also sci-fi enough, I think.
so haven's river (last thing mentioned) is actually consisting of millions (trillions?) of O'Neil cylinders all linked together to create the massive larger structure basically think of the O'Neil cylinders as beads on a string i very much recommend reading (or listening ) to the bobbiverse series
Rama is an O'Neill Cylinder and what brought that variation of the Oberth cylinder from the 1930s to the west's attention at least. (Similar were shown in sci-fi and futurism books from the Warsaw Pact nations years before Clarke and O'Neill published anything on them). So's Cooper Station, for that matter.
I was disappointed to see no Bishop Ring, defined as the biggest compatible with hard SF. The limiting factor is tensile strength of the the floor material, which is thus the most important detail of any design, limited by the strength of a covalent bond. Interestingly, the limiting diameter is proportional to the length a cable of the material can hold itself up, supported at the top, under the acceleration you want. For 1G, which is the only one we know is compatible with human biology, it comes out to about 1000 miles, and turns in something close to an hour. It is big enough that, with walls, you don't need a lid over. Inner surface area is New Zealand to Italy. You would build it as a thin ribbon, spinning it, and then widen that. Widening it from the center line would let you keep the walls up that hold the air in. At any time there would be long triangular holes along the center line with domes over them: cut some at the point, weld in a plate at the back, repeat. Any sufficiently advanced culture will not be reliant on a star's radiation for energy. Its biggest problem will be radiating away the waste heat from its high-energy operations, making cold the most precious commodity. It will locate its operations no closer to a star than its Kuiper belt, and that close only for ready access to material resources absent in interstellar space. Bishop Ring, given that it is actually possible in principle, deserves its own detailed episode. Certain practical problems remain to be solved.
"Any sufficiently advanced culture will not be reliant on a star's radiation for energy" what? Stars have more energy than the rest of the system combined. No sane culture would throw away these growth opportunities
1000 miles with zero safety factor. Baseline rigging safety factor is 10x, so you're looking at something more like 100 miles, not 1000. Still plenty large for a reasonable spin rate. Heating is a mostly solved issue as long as some of it is in shadow and solar heating is avoided in areas where it is not needed. Radiators do the rest of the work there. You can probably stabilize temperatures with thermal batteries and shade, so you really just have to deal with industrial cooling, which, again, thermal batteries are the answer there, no need to waste the energy if you don't have to. Also no real reason not to assemble it and then spin it up, then add the air/water/soil/etc. Far simpler. You will need rather high walls, and you likely need them to be transparent, at least variably, to let in sunlight to areas that need it. You also likely want a lid for similar reasons. If the walls are high enough the lid structure is simplified slightly because it's not experiencing 1g.
@@jttech44 If it's only 100 miles in diameter, you can just enclose the whole thing, like a hockey puck, or roof it over, donut-wise. You could anyway have a big hole near the hub to fly in through, too high for the air to get out. But anything that big merits the engineering attention to sail much closer to actual physical limits, more like aircraft and less like bridges. In space all the forces are perfectly predictable: tidal and thermal, mostly. But nobody would be willing to wait for it to all be done before they move in, so you need it livable while under construction. Nobody builds something like that unless they needed it yesterday.
Consider Phlebas was the first book that got me into reading properly. Read all the Culture books several times. Now I’m reading Neal Asher’s Polity series, there are similarities between the Culture & the Polity, I guess that’s why I enjoy them. Great video, thanks 🙏🏼
@@victor6250well they entered close to the only active of 9 gates in the outer shell. In that sense, they were still lucky, but not „with the Jackpot 23 thousand times over“ lucky. They simply saw the sentry drones preferred that gate and assumed Bender was carried through the same way. From There the resistance stole bender and saw now reason to move him further than the next regional headquarters in halebs ending(?).
I had the same question, when there is no drag (and in the almost vacuum of space there isn't) the tangential speed doesn't matter at all I would think. The only thing that is important for the material stresses is the centripetal force needed to hold everything together. And that is one g or below in all the examples. Thinking the centripetal speed matters is the same thing flat earthers are constantly yapping about when they say we should fly off the surface of the earth because it moves that fast
@@xerxis100 As I see it the bigger you go it is all about the tensile strength of your material. Basically having the material of ringworld would enable you to build a 100000000 km long suspension bridge. The best material we can come up with today has maybe 0.1% of the needed strength.
@xerxis100 You can build it in zero G but once it is spun up, the entire thing will be in tension. The larger it is, the more mass the entire thing has, and therefore the more force it exerts on itself to stay together.
The same spin creating "gravity" is a force also felt by the ring or cylinder, so the whole object wants to fly apart. It's being stretched out against itself. It's like getting spun on one of those things on the playground until you get thrown off.
I thought I remembered Niven claiming that he used to attend parties that local scientists also attended, and he got ideas for his stories, as well as help getting a hard sci-fi reputation, from them. And of course he did invent a fictional material to hold his Ringworld and its shadow squares together and in place, and described its properties.
@@idjtoal I forget if they ever got a close look, but do remember that they made that assumption. They also knocked a piece of connecting string loose in the first book, which proceeded to fall on and cut to pieces a civilization on the ring floor. In that case I think they confirmed more strongly that it was scrith.
Been a fan of Taylor and Weir for years, I am glad to see them getting some proper nerdom recognition! I did some calculations of a Dyson sphere, I think I came up with 21 billion times the surface of the earth, But I solved the gravity issue with mass by making it have a 12k km thick shell. I abandoned it though because that amount of mass could actually alter the internal gravitational forces of the star it surrounded. Fun thought experiment though.
@@oatlord Still, the maintenance was a huge problem. You're right to wonder about it. Please pass me some of that Tree-of-Life root and I'll help with the maintenance myself.
The maintenance and repair of the ringworld become major plot points in the sequels. One of the reasons it works is that the people managing it are superintelligent immortals genetically compelled to keep alive anyone genetically similar to them.
Oh dang! I forgot about the Bobiverse until I saw this video. I only got up to book 3 then forgot about it because of the gap, and now I'm seeing that there are 2 more?? Sweet! Fantastic video, btw. Thanks for making it!
OMG! Not only was I just reading about megastructures and compiling a table to compare them, but when I saw *Heaven's River* , my jaw dropped. Bobiverse is the best! 🤗
In "Xeelee Redemption" we have a ringworld 10,000 astronomical units in circumference, rotating with a tangential velocity near lightspeed. The idea is that by coming aboard you can make time slow down to an arbitrarily low level and wait out catastrophic events in safety.
The cylindrical gundam colonies from the UC timeline, or the hourglass shaped colonies from the Gundam SEED timeline would be nice contenders. They all seem pretty realistic.
I also didn't realize why we hadn't just built the dam things already until I saw Collapsing Land and The Scar of Space -- holy crap! The last 25 years is proof enough to me these things absolutely have to be able to split completely into survivable modules on vectors that definitely allow them to avoid becoming dangerous Earthbound debris. I'm not even happy about large habitats at the Lagrange points anymore.
I am working on a scifi universe that has artificial gravity but has some vintage stations that still use spin gravity so this video is very useful. Thank you!
Ringworld is mind-numbingly big. A 95 mile segment of it has the same area as all of the land on earth, and there would be ~6.3 million of those segments. Driving 24/7 on a highway straight across the width at 70 mph would take 370 days. An unbroken airliner flight would be in the neighborhood of 50 days.
I had the same question, when there is no drag (and in the almost vacuum of space there isn't) the tangential speed doesn't matter at all I would think. The only thing that is important for the material stresses is the centripetal force needed to hold everything together. And that is one g or below in all the examples. Thinking the tangential speed matters is the same thing flat earthers are constantly yapping about when they say we should fly off the surface of the earth because it moves that fast
In small scales it really doesn't, but you do have to impart the velocity which is an energy challenge. That said, i wouldn't trust any space"rock" to handle the loads other than ones made of solid metal. In the planetary+ scales you end up spinning faster than orbital speeds which means you could go interstellar accidentally on structural failure! And any spacerocks impacting would get an unfortunate speed boost relative to the surface, so cleaning those up beforehand is a must.
Yes. Spin doesn't actually create the force of gravity. The spinning force that creates the sense of gravity is felt by the object as well, tearing itself apart. All the pieces want to fly away in different directions.
@@corbinhirschhorn9064 sure, but that is still only affected by the angular velocity of the object and not the tangential velocity. In theory if you could build a huge wheel out of a very light exotic material and spin it around fast the tangential velocity would be enormous but the forces trying to tear the wheel apart would be small. All of this is just a response to the video where it's claimed the tangential velocity would be problematic
@@rinalds637 but once you start building planetary scale objects gravity would also pull everything back inside. And then you would have just gravity anyway and no need to spin the entire thing
One that you missed is Orbitsville (Bob Shaw). Its like Ringworld but its a Dyson sphere. It has an inner sphere which has a series of slots it is of varing sizes to give days as well as seasons. Needless to say its internal ares is redonculous!
I ususally just watch these videos for the 3d comparison, but the narration here was pretty good, it wasn't just a list of things, there were interesting facts about each of the elements. It was fun to watch.
The one thing I wish you did included was the Buthandi (sp?) from Schlock Mercenary. Probably not appropriate for this video because they generate gravity through fictional science. But it is a stellar enclosure which according to the author, the name translated into English is, "this was expensive to build"
How do you make a video about science fiction spin gravity and just not mention Gundam at all? Legit the most realistic and prolific examples of spin gravity in science fiction and just... not even on the map for you?
8:13 The day-night cycle comes from the ring's rotation, not its own shadow. The rotation speed is specifically designed so that half the day your surface is facing away from the sun. You tilt the ring so that it *doesn't* cast a shadow on itself (except twice a year when your tilt axis lines up with the sun).
8:20 I do not get the day/night cycle bit. In my mind, a ring inherently cannot cast a shadow on itself while the light source is a sphere within the ring. If you ever wanted to do a follow-up vid with a graphic for that, you'd be da boss EDIT: Ah, nevermind. The next graphic cleared it up! I thought the middle of the first ring example was the sun. I got you now. Great work!
As I understand from the description, those rings don't orbit a centrally-positioned star, but are in planetary orbits. Imagine that you took the Earth and replaced it with a ringworld in the same position and orbit, so that the centroid of the ringworld followed the Earth's orbit.
I love watching this video and actually have read several of the series mentioned. Normally when I see video like this I have no clue about the series they come from.
7:16 Maybe of the argue that they didn't always have artificial gravity. So it was built in the ring form to create spin gravity. And then it was just the design they kept
I remember 3 decades ago, when I was in Mechanical Engineer Polytechnic School, I got interested in rotating space stations (ring type) and worked out all the math formulas for stress on the shell depending on rotation speed and diameter and materials used (tensile strength and density and useful cargo on top). I found a NASA white paper and I had done it all right, I was so proud. I even found a small typo on their paper and emailed the authors. Back then Internet was so small, they actually replied >.
you achieved my dream right there, i wish i could be that proud of myself one day
I’m not an engineer and so I didn’t even try to calculate any stresses. It’s well beyond me.
I imagine you found the same paper I found when I was trying to figure out what was the smallest a ring space station could be to make inhabitants comfortable with low G and not throw up their lunch due to spin. I was doing this for a (hopefully) hard sci-fi story I was writing. My best determination was (I believe--it was a few years back) 50m diameter, a spin somewhere around 3RPM with a G close to between the Moon and Mars. I doubt the helpful sites I found back in 2008 are still there.
@@thatjeff7550 Was SpinCalc one of them?
If so, they're still going.
@OverviewEffekt interestingly, the math for rotating habitats is the same as a suspension bridge! The length of the bridge is the circumference of the habitat, and the stresses on it is the same as whatever material it's made out of under the same gravity that you're spinning it up to. I could be slightly incorrect or explained it poorly, but it's quite simple and mundane!
Handwavium, the miracle material!
Gravity plating with condensed material in micrometer strings held by electron degeneracy pressure from collapsing into black hole.....or something more even technical.
You can do anything with enough handwavium and renderite
Unobtainium
@@Extra.Medium Don't forget "Wantum Mechanics".
@@KnightRanger38 ooh that's a good one
1989. I was in college (undergrad) and joined the Traveller Mailing List. That's a sci-fi pen and paper RPG. The list started a group adventure about visiting a newly discovered ringworld, and I got put on the team to make content for the ringworld (yeah, three of us tasked to make 3 million Earths of content).
I'd gotten my hands on some 3D rendering software (we won't mention how), and tried making renders of what it would be like to actually see the ringworld, complete with fractal land, ocean, clouds. Remember, this was 1989. My poor little 80386 PC (with no math coprocessor) took 18-22 hours to render a single 640x480 resolution image.
This was all running under DOS - no multitasking. Meaning my computer was completely occupied and unusable while it was rendering. Another guy on the list tried using his work computer (a Sun Sparc I think) and it completed the render in 17 minutes. Those two factors made me give up after rendering just a few images.
It's nice to see the same thing rendered with modern hardware. Thanks for the trip down memory lane.
3D app, late 80's, 386, no co-pro so 386-SX, probs 25MHz clock.... maybe 33MHz.... Real early Lightwave?
I used POV-Ray and the modeler Moray back in '93 on a DX5-133, and a basic dive to the planet surface animation at 320x240 at 12fps took a couple of weeks to render, when my parents didn't turn the PC off at the power switch while I was in class.... Your pain is well understood. :)
Ah, Traveller, where, "You haven't lived, until you've died in character creation."
Even this was hard to render on modern hardware, though not that bad. About an hour per frame on on average on my GTX 1080 and had to use the (wonderful!) free render farm sheepit. It’s really the glossy floor that makes it hard. I had to use some tricks to minimize the light bounces in the floor. And had to render it multiple times to get all of the glitches out. I made the Ringworlds procedurally using blender's geometry nodes (which I’m addicted to) and it was actually pretty fun to do it that way. It could have been much better, but it’s always a time/quality equation you have to balance.
@@VerumAdPotentia or became so old you had to retire before you ever played
😆
The fact that you included the Bobiverse made me happy! :) ...... great book series
RIGHT
I was also pleasantly surprised at the addition of the Bobiverse! :D
Worst von Neumann probe ever
@@goliard20 and yet, still a great book series despite your opinion 😝😄
@@cobra6481 They are quoting the book; Bob literally says this lol
When I think spin gravity, my first thought is always the coriolis stations from Elite. It's where I learned the concept, and the ring stations from Elite Dangerous are the perfect mix of realistic functionality and far future technology.
For many people, the cylinder space stations from the Gundam series are iconic and a very important plot point in the series.
Thank you for adding Babylon 5!
Yeah the colonies in Gundam are pretty cool, was almost hoping they'd make an appearance but wasn't expecting it
THE GUNDAMS WILL SAVE US ALL!!!
@@jedisalamander2457 I was thinking the same. Though they're very close to the Ramma (especially the closed-type ones).
Yeah quite the oversight to not include Gundam. The designs were ripped direct from Gerard K. O'neill's work which is the seminal documentation on spin gravity space colonies.
@@jhnoakez They even called them "O'Neil cylinders".
Even in the Halo books they call out the fact that the Halos dont seem to operate on spin gravity, and the first Halo book was actually fairly hard scifi. Verbatim they say "the numbers dont check out".
As for why its a ring? Every gun needs a barrel.
Yeah maybe add that second bit in a spoiler for those who haven't played it nor read it and intend to. That's just being courteous.
@Unethical.FandubsGames I would but it's been spoiled at least a dozen times in the comments already and it's been a quarter of a century.
I'd say the cat's kind of out of the bag, don't you think?
Agreed. There's data from the books and source material (Like how the Expanse books provide detail on how Ceres was spun up, the TV series gets it wrong) that isn't shown here. Likely due to time constraints.
@@Unethical.FandubsGames Halo 3 came out in 2007
It is terribly inefficient to build such megastructures. All these sci-fi novels, films, series and the like are just spreading bullshit. It would be better to just inhabit a planet instead of these La La Land structures. It's always about gravity, but never about the fact that you can't just recreate an entire ecosystem without making compromises. At some point these wannabe planets would collapse because of their problems. Having to find a technical solution for every problem only makes things worse. More technology, more potential sources of error, etc... These things are rotating death traps.
You explained everything pretty well. One aspect you kind of overlooked is WHY someone would get nauseous on a smaller spinning hub like the 2001 example. The film shows Dave Bowman jogging inside. If he wanted an easy jog, he would jog anti-spinward. If he wanted a rigorous jog, he would run spinward. His ~10 feet per second added to the hub's angular velocity would increase his 'weight' noticeably. Also, just standing up from laying in bed. The inner ear would experience a noticeable centripetal acceleration change. And as mentioned about Bowman, moving spinward OR anti spinward would also wildly change the inner ear's acceleration.
Betting people could get used to just about any rotation after a while. None of the experiments ran for any length of time.
@@Akio-fy7ep Moving spinward, antispinward, radially in and out. . .all would effect the inner ear noticeably inside a small diameter hub. It would be like being aboard a smaller ship in rough seas. *One big difference in a hub* YOUR movement controls the acceleration fluctuations in a hub by moving in ANY direction as opposed to the sea controlling the acceleration change on a ship. NOT controlling random accelerations is MUCH more nauseating. So yes, I agree. I imagine it would be moderatly easier to get over the "seasickness" on a hub with a smaller radius. As is said in the video, once the radius gets to around 80 meters and the spin speed provides around 0.5g, the changes in accelerations by your movement become too small to notice unless your on a vehicle riding the hub's inner surface.
the Russians did a bunch of longer term experiments on Coriolis effects and they found that most people just get used to it after a week or two
I imagine that on a long enough timeframe at least some humans probably have the capacity to get used to the patterns and live problem-free long-term even at high-RPM. Probably they'd even get a sense for which way is spinward, from the tiny constant movements and the slight forces the spin would cause.
Yeah, I totally glossed over the Coriolis effect to focus on the other factors. Also some astronauts are legends made out of unobtainium and could handle anything. Probably Dave was made of this stuff.
If I remember correctly (big IF) Larry Niven's Ringworld was made out of a material called "Skrith". A physicist calculated that skrith had to have a tensile strength on par with the strong nuclear force to avoid being ripped apart by centrifugal forces. Great books, loved the video.
'Scrith', actually. Niven solved the lack of dynamic stability in the Ringworld by having the Pak builders put Bussard ramjets around the circumference, controlled to return the ring to its 'proper' position when it drifted out of place. The City Builders jerked the Ringworld over, once they found a way to cross through the ring walls, by dismounting the stabilizing ramjets to convert them into starships; after enough of the stabilizing ramjets had been removed, the Ringworld began to drift, to the point that it became necessary to fire the Ringworld's defense mechanism (a system mounted on the shadow squares to induce the star to eject a bolt of plasma) against the Ringworld's surface to push it back into line.
Well, scrith was (as I recall, anyway, it's been decades) explicitly a stable form of neutronium.
@@seanmalloy7249 That wasn't his point at all. He wasn't saying anything about the stability of the Ringworld (which was covered in the video) but the tensile strength of the structure so that it didn't break apart.
Great study! A follow-up study could be a survey of scifi novels about Dyson spheres.
And perhaps another one about black holes, bubble universes, worm holes, multiverses, etc.
4:31 what's interesting about the Elysium space station is that its torus is open on the inside, and the atmosphere is just held in there using centripetal forces. I did an estimation on that during my school time, and there is no way it can hold sufficient atmosphere at that size. Would need to be a lot higher g-force so people in the station don't suffucate, but such high forces would be too crushing.
They may have gotten the idea from Ringworld, but that structure has very high walls on the edges - hundreds of miles at least. (The book gives details, but it’s been decades since I read it.)
Exactly. It becomes obvious when you realise that the only reason we have over 100 kPa of pressure here on Earth's surface is that that there's a column of 10 metric tons of air above each square meter of surface, compressing itself with its weight more and more as you go deeper into the atmosphere. And that column is like 100 km deep here, more than the station's diameter.
why isn't the force sufficient to keep in the atmosphere? It (Elysium) is supposedly 1g, the same as Earth, and our atmosphere doesn't escape?
Elysium has open hangars into space too, so there must be some kind of force field tech.
It is terribly inefficient to build such megastructures. All these sci-fi novels, films, series and the like are just spreading bullshit. It would be better to just inhabit a planet instead of these La La Land structures. It's always about gravity, but never about the fact that you can't just recreate an entire ecosystem without making compromises. At some point these wannabe planets would collapse because of their problems. Having to find a technical solution for every problem only makes things worse. More technology, more potential sources of error, etc... These things are rotating death traps.
I just realised Endurance's 12 modules looks like a clock which ties in nicely with the whole theme of time in the movie.
tick tock tick tock *organ begins playing*
Yeah and it spins clockwise.
It reminds me of the Lab Ship (Type L) from Traveller.
Also 12 disciples, 12 tribes of Israel, 12 crew of the original Lazarus missions. Lots of religious callbacks in the story. The time parallel is very fitting though.
Gravity has never been proven; Never been detected, Never been observed. You need to prove against all other rationale that the reason an object drops is uniquely the act of gravity and nothing else. -You have to prove how all matter attracts all other matter indefinitely, and how that concept is why things fall. Helium balloons disprove gravity. Bumble bees disprove gravity - Their wings can't support their body weight. Gravity is a scape goat for all things that cant be explained
Halo is a ring because it's a weapon first, and a sanctuary second. It builds up energy in the middle of the ring for a while before firing, sending more energy into the accumulated mass from points all around the circumference.
IRL wise, it looks cool, of course, but that's the in-lore explanation
It also has the advantage of being able to, basically, hit itself. Seeing as the point of this weapon was to wipe out all organic life (above a certain level) in it's entire operating area, by making it a ring with the land facing inward it also hits it's own environment when fired.
The other reason for being a ring is likely because this shape means it will be the least in it's own way when that ball of death it builds up in the middle goes off.
No clue why it spins though.
@Amanoob105 Spinning makes it easier to stabilize. It's easier to maintain a constant spin than to stay perfectly still. It also causes day and night cycles for the ecosystems on the Ring, as seen in the original game
7 books into the Culture series and my life has been greatly enriched
Aren't they awesome? Favourite so far? I love Excession and Matter especially.
*Claps Dweller/Affronter/Idiran tentacles with excited appreciation*
@@kagirion *aura field turns rosy
All strong, Excession was an absolute banger, Look to Windward got me in the feels. Working my way through Matter now and the eons old shell world concept has been blowing my mind
@@CatProvider
Player of Games or Use of Weapons here
I just found your channel and ive been slowly going through your videos. Struggles at work kinda dimmed my enthusiasm for engineering but watching your videos gives me new energy and drive to get back into big projects! Thank you for the amazing job you do!
Don't let the puny humans get in the way of a good death-ray...I mean "the solid understanding and application of exciting engineering". :3
For anyone who hasn't read it, Project Hail Mary is excellent. I was a bit skeptical of it going in, but it ended up being my favorite of Andy Weir's novels.
The audiobook is fantastic.
Just waiting for the movie now
Nah, it was kinda lame.
I loved it but it had a few glaring logical issues. I'm still checking regularly when the next Andy Weir book is coming, tho 😅
They are making a movie out of it starring Ryan Gosling. I really want to see how they portray rocky. I hope a combination of excellent puppets and CGI
I love that you referenced "Project Hail Mary", such an unsung hero of books.... And the Bobiverse!!!! Great references in here!
You sleep, I watch.
fun fact: the guy who narrates Project hail Mary and the Bobiverse audiobooks is the same guy
@@commandline6749 and the far superior earlier version of The Martian - I love Wheaton when he reads Scalzi, but his version of Weir is just blah!
@@kalumbabwale3729 Good good good!
Project hail Mary is probably one of the most popular sci-fi books around right now, I wouldnt call it unsung by any stretch.
My favorite are the orbitals. A lot of sci-fi structures that big feel like they're going for the wow factor, but in the context of The Culture, the orbitals just seem like the most logical construction for a post-scarcity society that needs homes for trillions of beings. The fact that those people get to design the landscapes and live on big luxurious parcels of land if they want to just adds to the advanced future vibe.
All of these were great picks to include in this list -- great video!
@@adsilcott I also like that they generally *don't* live on planets - iiirc it's because the prevailing attitude is that planets should be left for species to naturally evolve upon,and more advanced species should leave them alone.
@@adamlytle2615 Culture loves being efficient
@@tappajaav if it's a matter of building a habitat vs terraforming a planet, then yeah the former is much more efficient. I like Isaac Arthur's analogy. Terraforming a planet is like hollowing out a big tree to make one tiny home, whereas building space habitats is like cutting down that same tree and using the lumber to make a much bigger house.
@@adamlytle2615 That's correct.
They also enjoy the flexibility of artificial platforms, and bypassing the territorial fighting that planetary estate often comes up with
@@adamlytle2615 Plus, the Culture considers terraforming a form of murder.
No idea how I never have run into this channel before. Definitely a fresh air of content to see. Thank you!
0:15 2 and 4 depend on 1 and 3. Only 1 and 3 are variables within the meaning of this video.
The Coriolis, Orbis and Ocellus starports from Elite: Dangerous are worth mentioning.
Coriolis would be especially interesting too look atbecause its a cuboctohedra
Oh hey, the exact comment I was about to make!
But yes, those are interesting because they actually have distinct rotational periods from eachother, and all their stats are listed on the wiki.
Also Orbis class starports can have two different sizes of habitat rings spinning at the same rate, meaning they'd have different internal gravity. (I say "can" because they're modular and not every Orbis has both or even any types of habitat rings.)
Elite: Dangerous does also commit the physics sin of spun-up asteroid bases, but natural asteroids in the game already spin unrealistically quickly, so I might give it a pass. :P
I couldn’t find any specs on them. Is there?
Also Ixion would be cool
@@OverviewEffekt just google "Elite Dangerous space stations" and go to the wiki of the game, there is specs for all types there.
I get so excited when someone mentions B5. It’s been 30 years, but the show still gets so little love. Thank you for doing this!
The Agamemnon from B5 is a pretty cool example, BTW. It’s Captain Sheridan’s old ship, about a mile long, with a large revolving section to simulate gravity, but rather than be a wheel like we commonly see, it’s basically two pie slices connected at the center, similar to the Leonov from 2010. Oh, yeah, and the Leonov is kinda cool, too, I guess (Forgot about it until the Agamemnon reminded me). Not saying you should do another video on the subject, I just thought I’d mention it.
Again: Thank you for doing this!
it's just excellent - that show is something else...
just started another rewatch of that show
@ i always rewatch it a little different if I can. One year I rewatched it with the movies in their proper places (Which is rough because Thirdspace takes place *inside* a regular episode) Another time I watched it, I stopped at “Objects at Rest,” then watched River of Souls, Rangers, call to Arms, Crusade, lost Tales, and THEN Sleeping in Light. This last time through I just skipped Season 5 entirely, and just jumped from “Rising Star” to “Sleeping in Light.” Each time it’s caused SiL to have a different emotional impact on me.
Agamemnon and the Omega Class ship design is a sci fi classic.
Be sure to catch Star Wreck, then, from the creators of Iron Sky.
Bablyon 5 was really good. The whole Shadow arc was amazing.
Finally! someone made ringworld to "scale" I wish you put a pov camera on every structure for comparison. very cool
Yeah i almost did that. I wish I had. But it took me months just to get this right and I didn’t know it would go viral… wish I had.
What thought went through my mind is that when you're speaking of these truly huge structures, could you not achieve gravity rather than by spin, by thickness of the ring? It's not Earth's spin that gives us 1g, it's her mass underneath us.
@@OverviewEffekt ‘viral’ with less work isn’t a bad thing, is it?
Another thing to consider:
How about a ring that is spinning more slowly (only for stability, perhaps), but closer to a sun -- so close that the actual gravity of the sun is pulling on it with the force of 1gravity?
The math would be the same as for Ringworld, but the living space would be on the outer surface with mirrored lighting instead of potentially dangerous additional moving parts.
There would still need to be something like the ramjets to nudge it in place but the bridge analogy Niven used for construction and strength still applies. 🤔
First time we encounter Halo in Halo CE, we see it with a PLANET in the background. Rampant gigantomania was added later, likely another fault of allowing novel authors to parasite on your IP.
Recently discovered the Bobiverse myself and binge-listened to the audio books of the series. It's awesome.
Another "space station" that would've been awesome to mention is the City from "Blame!", written by Tsutomu Nihei. Basically, the City is a spherical station that can expand itself, and because of plot reasons, the AI building the city started to continuously expand it without ever stopping. This leads to the "station" being just as big as Jupiter's orbit. In fact, at some point the protagonist enters a "room" big enough to encase Jupiter itself, suggesting the planet was entirely harvested. The whole size of the station is unknown, but it is at the minimum 9.6 billion kilometers in diameter.
Yeah, I think there are also a few mechs in anime that are colossal, and bigger than some of our planets. Can't remember which ones, but there was a breakdown of them somewhere.
@@animationcycles7109 isn't there a mecha bigger than the universe itself or something in Gurren Laggan lmfao?
Not really spin gravity though
The Bobiverse you’re such a great series and I wish more people would knew about it. I’m glad you brought it up. You’re the first person I’ve ever heard talk about it or mention it.
Ceres would 100% definitely disintegrate if it was spun up like that. Even solid rock behaves almost like a liquid on planetary scales, thanks to the square-cube law.
In the books I believe they covered the dwarf planet in some structure. I might be confusing that with the space dock that was located at the pole though.
You can 'easily' submerge a train track some miles under the surface, and suspend an endless train right under the surface. The train runs on a maglev suspension on its uhm "ceiling" ? This easily creates gravity. I am pretty certain the solar system can be colonized with "embedded" cylinders, little spinning like centrifuges. Angle them a little, so their conical shape compensates for the gravity of the asteroid or moon. In fact you can 'easily' replicate Earth's surface on the moon by constructing endless such embedded cylinders below the surface. Make em as big as a typical O'Neil cylinder (I built one together with Simon Deering in 2010 for Transvision conference) and you can have about 50% of Earth's surface - but with garden/eden level of comforts - so easily a hundred billion people.
Literally applying the same metric for Ceres, a dwarf planet like Ceres could have a population of, assuming one "layer" of habitats "only" (....) literally One Earth - about 8 billion people, living with a population level and relative spacing of The Netherlands.
Now if we were to start stacking the rotational habitats, plus a solidly reinforced structural envelope or "casing" on top of one another, say four layers deep, (some 20 kilometers on the moon) we can have hundreds of billions of people living on the moon. But at that scale the heat emitted by each habitat with all the BBQ's and swedish sauna's and such would become a problem.
If we build habitats all over the moon, 4 levels deep, and we assume several times USA levels of heat consumption, the waste heat could make the surface glow on the dark side in infrared at over 100 degrees Celsius.
@@Khannea i see, an isaac arthur enjoyer :)
My head canon is that it's not the whole dwarf planet that is spun up but underground centrifuges that is used to add to the natural gravity rather than trying to completely cancel it and reverse it as spinning the whole planet would need to do.
Glad you included Rama in this. The Rama book series is my favorite book series and I rarely ever hear anyone talk about it.
There is a movie in development based on the book "Rendezvous with Rama" by A.C. Clarke. I just hope the movie lives up to the standards of the book.
@@dexterford8094 Just found out this is to be directed by Denis Villeneuve. After what he did with Dune, I'm excited for the prospect of Rama.
@@dexterford8094 I remember hearing something about that recently. I hope they get it right. I've been telling people for years that it would make a great movie or TV series. I think a TV series would be the way to go. Especially when it comes to The Garden of Rama. There's just way too much to fit into a movie. A movie for Rendezvous with Rama would work if it was used as an introduction for a TV series that covers from Rama II onward. They could easily get 8-10 seasons out of it.
Because it was boring
Wait, a series? There is more than one?!
Holy shit dude! I just found my favourite channel on the platform, really awesome work - your videos are perfectly up my alley 😉
Actually the Hail Mary spins at about 3.45 rpm. The radius of the centrifuge isn't just half the length of the fully-cable-extended ship. The bulk of the ship's mass is in the non-crew compartment, making the center of mass much closer to that than the crew compartment. The radius of the centrifuge is 75m, making the diameter 150m.
Kudos for making a super interesting video on a subject close to my heart.
You touch on the angular velocity limitation of five or six RPM, but also the small size of Discovery means the crew feels significantly lighter at the head than the feet, not a comfortable feeling at all. The Coriolis effect would be wicked, too. Imagine playing centrifugal ping pong!
Oh thank you so much! I left Bobiverse on the second book. If only I had known this would be coming later. I loved this size comparison. The graphics here are _chef’s kiss_. Great job altogether.
Honestly the third book is the worst one imo, fourth one is fun so far
First one is the best one but they’re all pretty good.
@@MomirBacic I really enjoyed book 5, book 4 was too slow for my tastes and I didn’t enjoy the starfleet plotline. 1, 2, and 3 were great though, imo.
Finished 5 recently.
Looking forward to the rest of the possible decology+
Heaven's river drags a tiny bit but stick with it. Very well done.
9:21 I met Larry Niven once, and he told me that someone had made a scale model of the ring world at a convention he went to. crepe paper was used for the ring because it was the only thing cheap enough to make that massive of a circle lol. Also, Larry is one of the nicest guys you will ever meet. i had no idea he was even an author and i wasn't familiar with his books. He gave me a copy of his most recent book at the time after i talked to him for a bit
Trust fund, didn't need the money.
@@Akio-fy7ep That's great!
One of my favorite Sci-Fi authors.
The production quality and content of this video are outstanding, well done.
This was a cool video. I just finished the 5th Bobiverse book myself and LOVED it, I can't wait till the next book.
Your rendering skills really improved. Good job pal
Thanks. My rendering time also increased… lol. It’s mostly a time/quality trade off. I’m working on a gtx 1080 here…
7:21 So glad to see The Culture getting some love.
Some people daydream about living in Middle Earth or the Old Republic or what have you. I daydream about living on Masaq Orbital.
I was thinking one of the GSVs, personally.
I always preferred the ex ROU Psychopath Class - If I could ever get one to agree to me living on it!
What’s the appeal of being a pet to a bunch of AIs?
@@agonefire I never got the 'pet' vibe from all the books. More like 'we like other sentient things around, and we'll try and keep everything ticking over while everybody (including us) does their thing' from the AI's. Yes, it's technically a 'benign dictatorship' I suppose, but with god-like AI's that like having you around, it could be a lot worse?
@@agonefire they give the best belly rubs
The halo ring is a ring because it’s not REALLY a space station for its purpose. It’s a super weapon to eradicate all life in a radius
All hail the colossal space laser
Halo also isn’t hard sci fi
Spoilers lol
@@Daimo83 You really can't claim "spoilers" for a 20 year old game.
I mean saying it's not a space station because it's a super weapon is like saying the Death Star isn't a station.
It's very much a station, an Arc Ship, and a bunch of other stuff because it's a weapon, but it's primary purpose is to eradicate sentient life. The shape specifically facilitates the firing of the Instillations.
I loved this video, thank you for the graphics, it makes everything so much easier to understand.
Fantastic video, great work with the script but also with the easy to understand visuals.
Im Commander Shephard, and this is my favorite gravitational demonstration video on The Citadel!
Honestly a little bummed out that the citadel wasnt featured here, as im pretty sure it too uses spin gravity.
It very much does @@sidusher1726
It wasn’t long ago where a comment made a day after you made a vid wouldn’t be buried at the bottom of 800 comments. Very nice work friend. Love that you got the Bobiverse in there at the end. ✌️
When you mentioned the potential to get dizzy, I was surprised you didn't go into some of the weirder aspects of gravity via rotating cylinder: from the perspective of someone on the "ground" -- part of the rotating reference frame, as opposed to an observer watching the ring rotate from outside -- ballistic trajectories aren't the same as in a mass-induced gravity field. The smaller the ring diameter, the more noticeable the deviance from "normal" gravity.
Is it rotating or inertial? Can't be both
@@johnvonkerman Technically correct! The best kind of correct.
I meant "rotating reference frame" and edited my comment accordingly.
@@davidg5898 😂 how did you know the words I live by?
Ixion is a strategy game from a while ago, it featured The Tiqqun (pronounced: "tycoon"), it was a fun spinning space station! Also the OST for that one was amazing!
Fascinating, witty and AMAZING 3D Cad graphics. Thank you!!!!
There are the Iconian Dyson Spheres from Star Trek The Next Generation, we even get to see the Inside of 3 In Star Trek Online, The original Jenolan, the Solanae and the Herald Spheres. Star Trek also has Yorktown Station which also has a ton of handwavium involved but it is an interesting design with how it uses all of space with the artificial gravity letting people live on the different sides of those tunnels in it.
Yorktown Station was just absurd for something that was made before the time of the Original Series. I don't care if it's the alternate timeline, that thing was too advanced even for the ST: Picard setting.
Yorktown Station was far too advanced for human technology in Star Trek and is a good example of how the creators of the movie completely failed at world building
Was the Dyson sphere really Iconian? The extinct civilization with teleport technology from season 2, I think?
Sorry about the replies who think Star Trek is hard sci-fi. I assume literal children…?
@@RocketToTheMoose The Dyson sphere’s creators never came up in the show. The online game tends to make the fictional world smaller, more trivia-mongering and less imaginative, so the idea of the entirely separate Iconians making the sphere might come from there.
8:24 the Orbitals are angle so as to *not* cast a shadow on themselves. The angle allows the part of the inner surface facing the sun to recieve sunlight without it being blocked by the part of the inner surface facing away, which receives no light
Yeah his explanation made no sense, thanks for clarifying.
Heh Heh, I just made the same comment but you put it much more succinctly than I did!
The Gaea trilogy by John Varley deserves a mention. Titan,WIzard, Demon are the book's names.
Humanity finds a fairly stealthy artificial satellite in orbit around Saturn.
A crewed mission is sent to Saturn, and detects an artificial but LIVING Stanford torus, 1200 kilometers in diameter. It has an artificially dark surface ( vanta black before that was a thing ), and they can't really get any information from it, they theorise ( correctly ) that it is deliberately covert.
As they approach they detect that it has extremely low mass, so is obviously hollow. It is under spin, and as they pass by to measure its mass distribution, it exudes tentacles like a cuttlefish, and gathers in the earth-ship. Hy-jinks ensue.
Turns out to be an extremely old genetically engineered INTELLIGENT artifact, part of some civilisations' attempt to colonise the Galaxy. And they are successful, the Gaea the ship encounters is one of thousands in our solar system, and it is in contact with a countless community of others spread out across the galaxy.
The Gaea's arrive in a solar system as a seed, if they land on resources, they slowly grow up to size by much the same methods as a tree. In the process they eat up the planetoid they have landed on.
When they are fully loaded with the amount of resources they will need to thrive, they put themselves into orbit somewhere that they have a energy source, they do not need much. They ensure that their reaction mass ( the parts of their landing body that they don't need ) is launched at a tangent from their circumference, to give themself spin. During this phase, they are compact.
When they have made their orbit, they begin to inflate, melting the frozen gases they have gathered. They also grow and launch countless seeds, aimed extra-solar, again from their circumference to spin themselves up.
Inside they have complete and detailed control of the ecosystem that lives in the shell of the living world. And they have near miraculous genetic libraries and genetic engineering ability, and listening to Her "Sisters" among the stars, the Gaea can grow a vast library of creatures, from virus size up to whales.
Gaea Trilogy mentioned! I was at university when those books were new, and they were some of my favourites. One of my friends even went so far as to make a homebrew RPG with a Gaean setting.
Do not visit Cronus, he is quite insane these days...
I always wanted too see these turned into movies, but I guess there's too much sex.
Those are good books, but seem mostly forgotten. John Varley's earlier writings are incredible, but sometime between this trilogy and “Steel Beach” he came down with a chronic case of the Heinleins and it really ruined his later work. (The same disease cut Spider Robinson's career very short. At least Heinlein himself got a solid 30 years of writing done before succumbing to his namesake syndrome.)
@@mooseyard What is this stupidity you are claiming, in nothing more than parrot fashion.
I don't expect you can answer, with clear concise logic and proof.
You are running your mouth, in envy, of course.
Very cool video! If I remember correctly, Ceres in the Expanse has been heavily mined and its diameter was divided by two, its only 400km when the first book takes place. Also it's mentionned somewhere that the surface got glassed or melted by the Tycho engineers to help prevent the disintegration under spin forces.
Thanks you for a very cool illustration of ringworlds
Glad I waited to comment and bring in the bobaverse when you already addressed it. Thank you for the representation, I dont have a great imagination when it came to that structure.
Arthur C Clarke's books are highly recommendable. You just get sucked into these books, and his ability to describe something extremely complicated in very easily understood language, is amazing. The Rama series is a good place to start. Remember to eat, drink and sleep now and then as you just can't put his books down ! 🙂
There is also Outer Wilds with the Echoes of the Eye DLC. There the stranger is a spinning Space station. It's about 500m in diameter. As well as Stellaris, where you could find and build a Ring around a planet or even around a whole star.
OUTER WILDS MENTIONED LETZ GOOOO
I was about to say this exact thing
I found it so cool when I managed to get into the center and it was actually a 0g areas. The attention to detail is so impressive, especially because you have to piece everything together without any written history. I loved how they used heaters to make the still water warmer than the rest of the river, for example.
Stellaris really isn't a good example, since we get absolutely no specifications on any of the megastructures. Additionally Orbital Rings are a different beast to Ringworlds.
Gets even more fun if you use Gigastructural Engineering for Stellaris.
A singular ring world? Weak sauce! Put four in the same system.
Going further? Alderson Disk.
No limit? Birch World.
Thistledown in Greg Bear’s Eon would be interesting to see in your fantastic video treatment.
Even though the humans in that universe are advanced enough to alter universal constants, the infinite length of The Way would be a fascinating analysis.
Keep up the great work!
Thistledown would be somewhere around Elysium size. The entire diameter of The Way fits inside the asteroid, which was smaller than the moon.
Greg Bear wrote _Hull Zero Three_ which had an interstellar colony ship where each of the three hulls rotated for gravity. Or would do, if the ship weren't buggered.
I co-authored the first story bible for Halo and was a writer on Halo: Combat Evolved. I specifically wrote the bible's specs for the Halo ring, so I can tell you the bible indicated the ring spins fast enough to provide almost Earth-normal gravity (approximately .93 that of Earth).
The caveat about ancient tech "gravity wells" in the ring was added to the write-up to cover any scientific discrepancies that might arise later, so we could say the "gravity tech" made up the difference. But the ring was intended to generate most of its gravity from spin.
This may have been contradicted later (I left the franchise in 2003), but I did think about it and write it down at the very start (before the game was even released).
Really enjoyed your walk through of the various incarnations of this concept!
Coming from a real place, your song hit me in a real place!!! I'm with you 100%!!! Luv it! Luv it! Luv it!!!!! ❤❤❤!!!
The reason for the "spiral tunnels" on Ceres, is that the centrifugal force is being used *additively* to the gravitational force, not subtractively the way you depicted it. This creates increased perceived gravity along a cone shaped surface into the interior of the mass with the poles of rotation at the center of the cone and the point towards the center of the mass. Those tunnels are built along that conical surface. You could also live on the cone at the other pole with the same perceived gravity. The part that's unrealistic, is that the cone should be much more shallow, since it's only a mild increase in gravity. Also, Ceres is definitely not a "rubble pile" asteroid. It's surface is well studied and photographed up close at this point. It is quite solid.
Ohh, so Ceres itself isn't being spun up, just the cone section?
@@CODENAMEDERPY No, the whole thing is spun up, but when you calculate the combined effect of the spin with Ceres' own gravity, the ideal place to build tunnels to utilize the gravity is along the surfaces of those cones, which are mathematical illustrations and not physical structures.
@@harbingerdawn Would those tunnels be at the rotational poles?
"is that the centrifugal force is being used additively to the gravitational force"
Nope.
There is no surface where the gravitational and inertial (centrifugal) forces would add up positively. Way worse once you notice that the proposed force due to rotation is the same as surface gravity: It means that the regions furthest from the rotational axis of the planet are no longer bound by gravity and the whole thing would rip it self apart.
Gravity always is an inward-vector, centrifugal inertia is always outward.
The best you can do to "increase" gravity is to STOP all rotation - for earth that would make a person on the equator about 0.3% heavier - negligible.
The arrows are indicating the centrifugal force, not centripetal. Which might be a little confusing, but I thought it made the point clearer. It all varies on how big the tunnels actually are, and therefore how much centripetal falloff there is both laterally and towards the core. Either way, a tunnel circumnavigating the asteroid, like the Neom The Line city concept, would be ideal. Unless the tunnels are so small that the lateral falloff of acceleration in a cone shape is negligible.
The Gaia Trilogy by John Varley (books: Titan, Wizard and Demon) takes place in a Sanford torus that's an actual sentient entity. It's an extremely fun and bizarre trilogy that's hard to characterize.
I read Titan. It was an interesting, imaginative and fun read! There are two more books? I read Titan so long ago, I'll have to get my hands on all three. When I have leisure time...
@@DrunkenUFOPilot The three books (Titan, Wizard and Demon) all have different tones and get progressively more bizarre, but in a way that makes sense within the broader story. Demon is as tonally different from the first book as it can get and won’t make sense without the second book (Wizard). Demon is crazy insane- in the best way.
While none of these are my favorite Sci Fi novels, The Gaea Trilogy as a whole, is easily my favorite Sci Fi trilogy.
There's some way crazier stuff outside Science Fiction, in the realm of speculation, hypotheticals, and pure world-building. Isaac Arthur on TH-cam has some fantastic videos on the subject, and you can find all kinds of blogs and wikis that go over some crazier ideas with viability ranging from fantastical to clever and actually reasonable.
Love Isaac Arthur's content.
@@AlbertaGeek I could do without his incessant needs to claim CO2 is a 'control mechanism' of temperature. It sure fvckng isn't. ALL records have shown temp proceeds CO2- temp up CO2 then goes up, and the reverse as well.
Don't even need to have a thermodynamic background (which basically not ONE person pushing the CO2 bllsht has, and computer models are not field observations) to prove this. Walk into the fvckng shade! LMAO 20-25f drop in temperature IMMEDIATELY.
@@AlbertaGeek It's always entertaining, but frequently over the top.
Sides/Colonies from UC and AC Gundam (Mobile Suit Gundam and Gundam Wing, respectively). I wouldn't know where to start with scaling, but it would be awesome to see in perspective.
Awesome vid!
* contingent sigh*
I had a really hard day... And this video just made me so happy. Just... Happy. Content.
You have a gift, and thank you for exercising it! Please continue!! 💗💗💗💗💗
Where are the O'Neill cylinders, like from Gundam? I figured those would be pretty big? If it's too realistic, it's also used in many of the Gundam Series, so it's also sci-fi enough, I think.
so haven's river (last thing mentioned) is actually consisting of millions (trillions?) of O'Neil cylinders all linked together to create the massive larger structure basically think of the O'Neil cylinders as beads on a string
i very much recommend reading (or listening ) to the bobbiverse series
Rama is an O'Neill Cylinder and what brought that variation of the Oberth cylinder from the 1930s to the west's attention at least. (Similar were shown in sci-fi and futurism books from the Warsaw Pact nations years before Clarke and O'Neill published anything on them). So's Cooper Station, for that matter.
Babylon 5 is an O'Neill cylinder as well
It’s tiny in this context but the citadel in mass effect
@@genericusername5909 it's at least got a pretty unique design!
I was disappointed to see no Bishop Ring, defined as the biggest compatible with hard SF. The limiting factor is tensile strength of the the floor material, which is thus the most important detail of any design, limited by the strength of a covalent bond. Interestingly, the limiting diameter is proportional to the length a cable of the material can hold itself up, supported at the top, under the acceleration you want. For 1G, which is the only one we know is compatible with human biology, it comes out to about 1000 miles, and turns in something close to an hour. It is big enough that, with walls, you don't need a lid over. Inner surface area is New Zealand to Italy.
You would build it as a thin ribbon, spinning it, and then widen that. Widening it from the center line would let you keep the walls up that hold the air in. At any time there would be long triangular holes along the center line with domes over them: cut some at the point, weld in a plate at the back, repeat.
Any sufficiently advanced culture will not be reliant on a star's radiation for energy. Its biggest problem will be radiating away the waste heat from its high-energy operations, making cold the most precious commodity. It will locate its operations no closer to a star than its Kuiper belt, and that close only for ready access to material resources absent in interstellar space.
Bishop Ring, given that it is actually possible in principle, deserves its own detailed episode. Certain practical problems remain to be solved.
"Certain practical problems remain to be resolved."
A simple matter of engineering!
"Any sufficiently advanced culture will not be reliant on a star's radiation for energy" what? Stars have more energy than the rest of the system combined. No sane culture would throw away these growth opportunities
1000 miles with zero safety factor. Baseline rigging safety factor is 10x, so you're looking at something more like 100 miles, not 1000. Still plenty large for a reasonable spin rate.
Heating is a mostly solved issue as long as some of it is in shadow and solar heating is avoided in areas where it is not needed. Radiators do the rest of the work there. You can probably stabilize temperatures with thermal batteries and shade, so you really just have to deal with industrial cooling, which, again, thermal batteries are the answer there, no need to waste the energy if you don't have to.
Also no real reason not to assemble it and then spin it up, then add the air/water/soil/etc. Far simpler. You will need rather high walls, and you likely need them to be transparent, at least variably, to let in sunlight to areas that need it. You also likely want a lid for similar reasons. If the walls are high enough the lid structure is simplified slightly because it's not experiencing 1g.
@@jttech44 If it's only 100 miles in diameter, you can just enclose the whole thing, like a hockey puck, or roof it over, donut-wise. You could anyway have a big hole near the hub to fly in through, too high for the air to get out. But anything that big merits the engineering attention to sail much closer to actual physical limits, more like aircraft and less like bridges. In space all the forces are perfectly predictable: tidal and thermal, mostly.
But nobody would be willing to wait for it to all be done before they move in, so you need it livable while under construction. Nobody builds something like that unless they needed it yesterday.
I agree that bishop rings are awesome, but is there any example of one in fiction? I can't think of any.
Consider Phlebas was the first book that got me into reading properly. Read all the Culture books several times. Now I’m reading Neal Asher’s Polity series, there are similarities between the Culture & the Polity, I guess that’s why I enjoy them.
Great video, thanks 🙏🏼
I am so glad that you referenced the Bobiverse books! Absolutely slept on.
The visualization of heavens river really puts into perspective how lucky the bobs were when they were looking for benders matrix
How was it they located the section he was on? I forget. Did they just scan until they detected him?
Good ol' Anek-23 🤗
@@victor6250well they entered close to the only active of 9 gates in the outer shell.
In that sense, they were still lucky, but not „with the Jackpot 23 thousand times over“ lucky.
They simply saw the sentry drones preferred that gate and assumed Bender was carried through the same way.
From
There the resistance stole bender and saw now reason to move him further than the next regional headquarters in halebs ending(?).
@@harriehausenman8623i‘m still not quite at ease with him. But the fact he hates beer is pretty endearing 😂
@@anticlaassic give him some slack. he had a really tough youth 😄
Why is the tangential speed an issue? It only has to accelerate the material in the ring at 1 g. Is tension the issue? If so, why not say so?
I had the same question, when there is no drag (and in the almost vacuum of space there isn't) the tangential speed doesn't matter at all I would think. The only thing that is important for the material stresses is the centripetal force needed to hold everything together. And that is one g or below in all the examples. Thinking the centripetal speed matters is the same thing flat earthers are constantly yapping about when they say we should fly off the surface of the earth because it moves that fast
@@xerxis100 As I see it the bigger you go it is all about the tensile strength of your material. Basically having the material of ringworld would enable you to build a 100000000 km long suspension bridge. The best material we can come up with today has maybe 0.1% of the needed strength.
@@davidvanwetswinkel8992 also not a problem if you build in zero g?
@xerxis100 You can build it in zero G but once it is spun up, the entire thing will be in tension. The larger it is, the more mass the entire thing has, and therefore the more force it exerts on itself to stay together.
The same spin creating "gravity" is a force also felt by the ring or cylinder, so the whole object wants to fly apart. It's being stretched out against itself. It's like getting spun on one of those things on the playground until you get thrown off.
So glad to see The Culture series get it's due here.
agreed.
yep
Phenomenal video. Easily won a subscriber!
Nailed all the ones I was hoping! Awesome video.
I thought I remembered Niven claiming that he used to attend parties that local scientists also attended, and he got ideas for his stories, as well as help getting a hard sci-fi reputation, from them. And of course he did invent a fictional material to hold his Ringworld and its shadow squares together and in place, and described its properties.
were the shadow square wires made of scrith also ? not saying they weren't, it's been a while since I read any of those.
@@idjtoal I forget if they ever got a close look, but do remember that they made that assumption. They also knocked a piece of connecting string loose in the first book, which proceeded to fall on and cut to pieces a civilization on the ring floor. In that case I think they confirmed more strongly that it was scrith.
@@idjtoal They were. The Pak used it for pretty much everything.
@@AlbertaGeek It should have been superconducting.
@@Akio-fy7ep Yes, but that would have made it the _ultimate_ unobtanium. Had to leave something for the plot, right?
Been a fan of Taylor and Weir for years, I am glad to see them getting some proper nerdom recognition! I did some calculations of a Dyson sphere, I think I came up with 21 billion times the surface of the earth, But I solved the gravity issue with mass by making it have a 12k km thick shell. I abandoned it though because that amount of mass could actually alter the internal gravitational forces of the star it surrounded. Fun thought experiment though.
Imagine being in the maintenance department on the ring world.
I think you'd have a sector you're assigned to, rather then being sent all over the place
"The Ringworld Engineers" goes into this very thing.
@@fantabuloussnuffaluffagus I guess I'm not as clever as I thought.
@@oatlord Still, the maintenance was a huge problem. You're right to wonder about it.
Please pass me some of that Tree-of-Life root and I'll help with the maintenance myself.
The maintenance and repair of the ringworld become major plot points in the sequels. One of the reasons it works is that the people managing it are superintelligent immortals genetically compelled to keep alive anyone genetically similar to them.
The whole time I was hoping for Heavens River, then when you said the ones from the expanse it got me even more hopeful. This didn't disappoint!
Oh dang! I forgot about the Bobiverse until I saw this video. I only got up to book 3 then forgot about it because of the gap, and now I'm seeing that there are 2 more?? Sweet!
Fantastic video, btw. Thanks for making it!
OMG! Not only was I just reading about megastructures and compiling a table to compare them, but when I saw *Heaven's River* , my jaw dropped.
Bobiverse is the best! 🤗
Bolder’s Ring from the Xeelee sequence would be a fun comparison just for the insanity
In "Xeelee Redemption" we have a ringworld 10,000 astronomical units in circumference, rotating with a tangential velocity near lightspeed. The idea is that by coming aboard you can make time slow down to an arbitrarily low level and wait out catastrophic events in safety.
The cylindrical gundam colonies from the UC timeline, or the hourglass shaped colonies from the Gundam SEED timeline would be nice contenders. They all seem pretty realistic.
I also didn't realize why we hadn't just built the dam things already until I saw Collapsing Land and The Scar of Space -- holy crap! The last 25 years is proof enough to me these things absolutely have to be able to split completely into survivable modules on vectors that definitely allow them to avoid becoming dangerous Earthbound debris.
I'm not even happy about large habitats at the Lagrange points anymore.
cute konata pfp
Yeah. Those are O'Neill cylinders
@@GeoffFrizzell-kz3rg You might as well come out against interplanetary travel at all. The size hardly matters compared to the velocity.
love that you mentioned the culture, they don't get mentioned enough.
I am working on a scifi universe that has artificial gravity but has some vintage stations that still use spin gravity so this video is very useful. Thank you!
Ringworld is mind-numbingly big. A 95 mile segment of it has the same area as all of the land on earth, and there would be ~6.3 million of those segments.
Driving 24/7 on a highway straight across the width at 70 mph would take 370 days. An unbroken airliner flight would be in the neighborhood of 50 days.
Just take the space train thing that runs along its edges! Even that would probably still take forever to go around the whole thing though.
Good thing the ships are fast, "space pilots tend to forget that Mach 4 in an atmosphere is _fast."_
@@BinkyTheToasterthat’s still not fast enough to visit your friend who lives on the other side though.
@@cjeam9199 easy,.. just jump out of gravity, fart, wait, wait,fart the opposite way, land tadaa
@@cjeam9199 Mach 4 isn't, but this is a spacecraft we're discussing; it'll make like Mach 20000 before you have to engage the hyperdrive to go faster.
Does tangential velocity really matter though if the acceleration is still only 1 g?
I had the same question, when there is no drag (and in the almost vacuum of space there isn't) the tangential speed doesn't matter at all I would think. The only thing that is important for the material stresses is the centripetal force needed to hold everything together. And that is one g or below in all the examples. Thinking the tangential speed matters is the same thing flat earthers are constantly yapping about when they say we should fly off the surface of the earth because it moves that fast
In small scales it really doesn't, but you do have to impart the velocity which is an energy challenge. That said, i wouldn't trust any space"rock" to handle the loads other than ones made of solid metal. In the planetary+ scales you end up spinning faster than orbital speeds which means you could go interstellar accidentally on structural failure! And any spacerocks impacting would get an unfortunate speed boost relative to the surface, so cleaning those up beforehand is a must.
Yes. Spin doesn't actually create the force of gravity. The spinning force that creates the sense of gravity is felt by the object as well, tearing itself apart. All the pieces want to fly away in different directions.
@@corbinhirschhorn9064 sure, but that is still only affected by the angular velocity of the object and not the tangential velocity. In theory if you could build a huge wheel out of a very light exotic material and spin it around fast the tangential velocity would be enormous but the forces trying to tear the wheel apart would be small. All of this is just a response to the video where it's claimed the tangential velocity would be problematic
@@rinalds637 but once you start building planetary scale objects gravity would also pull everything back inside. And then you would have just gravity anyway and no need to spin the entire thing
Rama and Hailmary mentioned 😊
One that you missed is Orbitsville (Bob Shaw). Its like Ringworld but its a Dyson sphere. It has an inner sphere which has a series of slots it is of varing sizes to give days as well as seasons. Needless to say its internal ares is redonculous!
I ususally just watch these videos for the 3d comparison, but the narration here was pretty good, it wasn't just a list of things, there were interesting facts about each of the elements. It was fun to watch.
I love this video, and I love your inclusion of Project Hail Mary and Rama, but why didn't you include Hermes from The Martian?
It just didn't make the cut... :-(
The one thing I wish you did included was the Buthandi (sp?) from Schlock Mercenary. Probably not appropriate for this video because they generate gravity through fictional science. But it is a stellar enclosure which according to the author, the name translated into English is, "this was expensive to build"
In Schlock Mercenary there's the spingrav Credomar habitat.
IIRC Buuthandi is shorthand for the phrasw "Buut go buut-buut nnaa-nnaa cho handi".
Should also look into Eina-Afa the "Can Full of Sky"
How do you make a video about science fiction spin gravity and just not mention Gundam at all? Legit the most realistic and prolific examples of spin gravity in science fiction and just... not even on the map for you?
Some people are just anime racist.
Nice to see The Culture get a mention, and to visualise the size of the Orbitals!
I love this so much. I've been intending for years to work out the math for an Earth-friendly ring, but this is far better.
8:13 The day-night cycle comes from the ring's rotation, not its own shadow. The rotation speed is specifically designed so that half the day your surface is facing away from the sun. You tilt the ring so that it *doesn't* cast a shadow on itself (except twice a year when your tilt axis lines up with the sun).
8:20 I do not get the day/night cycle bit. In my mind, a ring inherently cannot cast a shadow on itself while the light source is a sphere within the ring. If you ever wanted to do a follow-up vid with a graphic for that, you'd be da boss
EDIT: Ah, nevermind. The next graphic cleared it up! I thought the middle of the first ring example was the sun. I got you now. Great work!
I thought the same exact thing because Ring World is just engraved in my mind, no instead it's just a kinda small station orbiting a star.
@@man-from-2058 The shadow squares should have had more-clever shapes, to emulate twilight. Perforated at the ends, maybe.
As I understand from the description, those rings don't orbit a centrally-positioned star, but are in planetary orbits. Imagine that you took the Earth and replaced it with a ringworld in the same position and orbit, so that the centroid of the ringworld followed the Earth's orbit.
Id probably add birch world as the grand pappy of them all
Was looking for someone mentioning Birch world
A sphere around SMBH... it is BIG.
Birch World doesnt spin for gravity, it uses the SMBH at its center for gravity as a shellworld
@@fiiral5870 true, but would not be that out of place here
@fiiral5870 you are correct, I retract my recommendation.
Then a recommendation for a future vid. Habitable megastructure scale maybe?
I love watching this video and actually have read several of the series mentioned. Normally when I see video like this I have no clue about the series they come from.
Bobiverse is an amazing series. Big points for covering it in the video.
7:16 Maybe of the argue that they didn't always have artificial gravity. So it was built in the ring form to create spin gravity. And then it was just the design they kept
10:18 absolute nerds
Absolute units
12:11 whoever wrote that misspelled. Second paragraph, 3rd to last line, should be "engineering challenges *than* "
🤓
I was waiting for Heavens River but thought the book was too small to have made it into this video. I was so excited when you mentioned it!
Such a good video. Love the Culture books and Bobiverse and this was just brain candy!