It's a writer's daydream and impossible for basically every reason imaginable... Or as Elon Musk would put it "90% complete and will be commercially available next year."
Hi, I work for a cutting-edge high-tech corporation. "90% complete" means that the design is not even finished and there is no design-freeze yet. Nor has it been built. Nor has it passed the absolutely brutal performance-tests that are required to test for long-term viability.
Don't forget it would probably solve the world hunger issues. You have to make at least one promise that has nothing to do with the project too. Muskology.
@@MyKharliand why not just forget the anchor for the tether? Just build a symmetrical system with two space elevators going from antipodes and connect the cable from one with the other through a big hole running through Earth's center. I've heard there is now a company which made boring such tunnels much cheaper as it has ever been.
One potential correction if I may. The concept usually involves a cable that reaches beyond geosynchronous orbit and which is terminated above geosynchronous orbit with a counter weight. Now, if you graph the tension in the cable, the highest tension is at the point of geosynchronous orbit. The tension in the cable reduces as you move towards the ground. Which is what you expect because each point in the cable has less cable below it that it is holding up. In theory at least, when you reach the ground, the tension is zero. Of course adding a load will add to that tension, but the tension is supported by the cable from above. What I'm saying here is that although you need an anchor point, you do not need a massive anchor point since ground level is where you see the lowest tension. In fact you can actually tether this to a floating ship or floating structure of sufficient mass. Also, the counterweight (beyond geosynchronous orbit) is actually moving faster than geosynchronous speed. If you release an object from this point, it will go into an orbit that dips above and below the orbit of the counterweight. It won't get you into escape velocity, but it will get you most of the way there. At least in theory. Yes, its impractical with today's technology. But being the pedant I am, I figured I should correct those bits :)
You have it exactly backwards, the ground is where the greatest tension is. That's why you need to hold the cable down, if the tension was zero it would be floating.
@@PlatinumAltaria No, wrong. The greatest tension is at geostationary orbit. The cable is being pulled by the counterweight beyond geostationary orbit and below geostationary orbit the cable hangs. I know its counter intuitive to some, but that's the actual physics. Now, you do need to apply some additional tension to the cable to keep it reasonably straight against other forces and that additional force needs to be resisted by the ground, but that's a small force compared to the cables own self loading. A few tens of thousands of tonnes (a big ship) is sufficient to this task. Think about it. You have a fixed point in geostationary orbit. You lower a cable from there. Every km you pay out is additional mass that has to be supported by the cable above it. Hence the tension rises the further you go up.
3:24 Okay I actually laughed out loud at this reveal, after marveling at how long it would have taken me to find the location on Google Earth and then wondering why they chose Disney of all places. Thank you for including the process even though you could have skipped it!
Anyway. Arthur C Clarke has already specified (sort of!) where one of the few viable places on earth to build it, is. He suggested Adam's Peak /Sri Pada in Sri Lanka due to its proximity to the equator.
@@backalleycqc4790 Honestly that kind of depends on how you define Colonising. If it means making a limitted permanent pressence on Mars that does seem possible with current tech. It would require a genuine protracted effort but a small permanent research station like the ones in Antarctica (granted it would be a lot hard and would likely take a couple decades to achieve) it is not out of the realm of possibility of current technology. But if you mean a proper civilian colony on Mars working then yes I 100%.
@@mittelwelle_531_khz They could have but the political climate as well as a differing technological pathway pulled the resources away to more important projects.
We really should combine this with SpinLaunch technology, spinning out the tether on demand! Hereby, I give the world the Space Chameleon, AKA, the HyperLick - it's that easy, really.
Subscriber to you as well as this channel. This video did a great job of specifying LEO in the title. Which anyone who has taken a simple orbital mechanical class knows is impossible. A space elevator ONLY makes sense for deep space (IE, higher than geo stationary) destinations. Yes, we currently don't have materials strong enough to handle going from ground to geostationary. Simple as. But if we could somehow lift things past geostationary orbit, it would be amazing for getting payloads into deep space.
Hyperloop is impractical because the tube has to be in vacuum, right? There is plenty of vacuum above 100,000 feet. Now lets talk about electrifying the cable. You now have a very long rail gun or maglev track if you prefer. I agree that the cable anchor has to be at the equator but the terminus has to be at geosynchronous orbit with a big counterweight. If you need to have satellites at LEO, I would think it would be possible to build way stations anywhere along the length of the cable. Lastly, any cable strong enough to support it self and facilities and the counterweight, should be able to withstand space debris hitting it. It seems like you have a very narrow cross section so that most space junk would miss it.
Space Escalator. I'm telling you, guys. Not region Locked. Makes it's own electricity. Creates and controls weather patterns. Cools the planet. Launch platform is Already moving at speed, just let go.
I always assume the topic of space elevators for scientists is just a thought experiment in the absurd to get the mind thinking about things. Kind of like when someone in disaster preparedness thinks about how to prepare for a zombie apocalypse. You don't actually think it can happen, but what are the types of problems you would face, and how could you potentially solve them. We seem to do this sort of thing a lot in tech. We imagine an absurd way to solve a problem of we had an unlimited budget. But sometimes, that brain storming picks up on an idea of part of it that simplifies and works for the actual problem we were trying to solve.
Space elevators were a semi serious proposal for how to lower launch cost, the basic idea being that rockets spend a lot of their energy just carrying fuel and fighting air resistance. A space elevator would just be fed energy continously so it doesn't need to carry it's fuel and it could move slowly enough where air resistance isn't an issue, you could even just have it inside a depressurized tube. Then once you get to the desired height you could simply just launch the payload into orbit using something like a mass driver. This is basically the same idea that's behind all forms of space infrastructure. The issue with space elevators were many, firstly they're huge and have to be built at the equator, the cables need to be unnaturally strong, actually delivering power to the crawler is really difficult, and if the cable snaps it'd whiplash around the equator in the single biggest industrial disaster ever. However as you mention it is sorta like preparing for a zombie apocalypse in that by thinking out this scenario you learn what you actually want. A space elevator is like the best possible space infrastructure you can imagine, short of magic like teleportation there is no possible way to make it cheaper to launch things into space. So every other form of space infrastructure tries to approach all of the upsides of a space elevator while negating the negatives, space tethers are one example of much more realistic space infrastructure that actual companies have done research into, reuseable rockets are another idea.
Once it exists, it'd be great because you could lower the cost of getting materials to space, but more importantly, increase the frequency of such trips, *but* no materials exists that can do such a thing and by the time we have it, we'd probably have just gotten to other planets with rockets anyway.
@sedalionthunder6295 the problem isn't the idea, the thought experiment, or the pretty cool looking restaurant at Disney. The problem is turning the idea into a con and taking money from hopeful people.
Isaac Arthurs channel did some really good discussions on space elevators and an orbital ring as means of getting payloads into orbit more easily. And yes, its a long way from being even remotely practical.
Isaac has some really good content and does a great job pointing out the realistic, hypothetical, and scifi parts of his discussions. Ive been watching him for years.
Couldn't help imagining several thousand kilometers of thick cable falling through the atmosphere, directly above. Like many dangerous things, it looked really cool.
@@anno5936what? The part above the break might do this depending on the forces to that lead to the break, everything else is coming down because it does not have enough perpendicular speed to overcome the gravitational pull.
Halo 3: ODST actually shows you what a space elevator "collapse" would look like. When the New Mombasa tether finally gives way, it gets yanked into orbit by the centrifugal forces of the counterweight, dropping bits of support structure as it flies away.
As always, it's a lot easier to make a CGI video than actually work through the engineering challenges. I have met plenty of 'idea guys' in my career. They throw out impossible or near impossible concepts and then get frustrated and angry when engineers tell them why it's not going to work.
Engineering challenges were worked out well over a decade ago. It's not even that expensive. Is just an idea that sounds so crazy nobody is willing to actually take it seriously. First of all you use Rotating Space Elevators (RSEs from now on). Imagine a wheel traveling along the ground. If your car is going 20 freedom units per hour, then your wheels are going from standing still to going 40 freedom units, in a sine wave. Now make that wheel double the length of low earth orbit. Now get rid of the wheel and just make it a ribbon about 3 ft wide and a couple of micro freedoms thick. Every time it goes around when it hits the bottom it will be stopped. All you need is a hook on the end. By having adjustable mass at the center station, weight going down, cancels out weight going up. So assuming some sort of peerage agreement is worked out, that's a "free" ride to orbit. You can increase or decrease the amount of tethers arbitrarily, so scaling is easy that way. And you can put them in progressively higher orbits. That also means you can use them for deceleration. Meaning faster transit times, and getting paid for extra momentum. Does a bunch of other cool stuff. Does it take any unobtainium. I'm pretty sure according to the math, regular kevlar would work.
@@jtjames79 Nothing you said was true, Mr Idea Guy. The engineering challenges have NOT been worked out and no material in existence now or even prophesized in the future is up to the task. You've been watching too many Pop Sci channels apparently or ... your comment was all in jest
I think that orbital rings, Mars colonies, and O'Neill cylinders are reasonable. To make in 2500. Space Elevators are their own kind of difficult though. I could see us building them, again in hundreds of years, but they just don't seem practical around Earth. And the maintenance of an orbital ring would be... quite the problem. It's the sort of thing where world peace would help a lot.
Orbital ring maintenance is only hard if you are building a single ring. You want to build several rotor/stator pairs and can shut them off in turns to do maintenance.
Space elevators are just so much worse than orbital rings for Earth orbit, that they're not in the same category as orbital rings. But yeah, maintaining a maglev train 40 000 km long is going to be a bit of work.
I think they could be made before then, but we have to be in space and have worked out the whole "fuel supply to bring in asteroids for materials" thing.
The thing known in tabloid level media as the "O'Neill cylinder" wasn't ever proposed as a realistic thing, but was only ever an illustration of the sort of scale of things that modern realistic engineering might do. O'Neill said it's probably not workable (we know it isn't) and is about as realistic to the people 80 years after the first generation small habitats are done, would build when they need a place for millions of people, as what "futurists" in the 1890s thought that the year 2000 would be like. Scale your expectations back to O'Neill's "Island One" 800 meter diameter habitat, or the NASA Ames "Stanford Torus" 800 meter radius, and it's entirely do-able. The '70s NASA Ames space settlement studies found that no new inventions are needed to mine asteroids and moons and to build for virtually Earth-like conditions anywhere in space where there are or to which we bring materials. The first habitat for 10k workers, along with all the ground, launch, and in-space infrastructure to reproduce it or to build Solar power satellites would have been done by 2010. The cost would have been like many other large infrastructure or industrial developments down here. Like the Interstate Highway System, or like ≈4 of our CVNs and their air wings & escorts and the logistics infrastructure to deploy them. Far less than a small oil war or the bailouts we've seen. Less than what they projected that we'd need to spend to meet new electrical grid power in the same time frame (and we've spent far more than they projected). Eventually when space manufacturing of very large structures is built up and they need the living space, the largest pressure vessel that we could build with then-known technology to spin for 1 G and hold shielding and everything inside, was ≈30 km diameter, by maybe half as much in length (drum shape, instead of cylinder). Concrete & steel. No nanotech self-replicating 3D printing of magically huge amounts of graphene, required. With titanium (which isn't rare out there) instead of steel, maybe twice as big. Any who disagree with this is invited to show their qualifications in mining, construction and astronautical engineering and where they've published under peer-review saying that those studies were wrong. Note that before the first hab for the workers is done, the effort has paid back and ended all questions of budget or cost, with NEA metals. All objections against NEA mining of previously rare or precious or monetary metals brought back to Earth markets boils down to the lead time and scale of the effort. Yes, it's 25 years away, for NEA mining or Solar power sats to return anything big. It's been 25 years away since the '70s. As for a Mars colony (which is a place where people will retire and raise children): Prove that we can live long-term and stay healthy in low G. That's "proof", not S.F., not wishes and hopes that the question goes away and try it and see. Not maybe in the future biomechanically altering ourselves and our offspring. Prove that first, and we can go on to talk about why O'Neill/Kalpana/Stanford Torus habitats in space are still the better or only option for long-term, large-scale habitation off-Earth.
Sticking it in a spot it would fall over the ocean and including explosive charges to cut it at a point that limits how much cable falls you could limit risk solely to your own country. Obstructing so many orbits is some thing else though.
In sci fi I’ve read the elevators can take days to get to altitude. In K Stanley Robinsons 2312 the elevator riders enjoy their ride time by learning parts for a space opera and performing in a grand theatre. The elevator is like a large hotel.
That's really the idea, rockets need to go fast to get anywhere and this means they have to deal with a lot of air resistance. A space elevator could go as slow as it wants and therefore not a lot of energy would be lost to air resistance.
Vaporware company: We've solved the science of space elevators. CSS: How? Vaporware company: Step one involves making billions of dollars vaporize. CSS: So magic then? Vaporware company: Ta-Da!!
You are correct about the tech not existing for an Elevator or Orbital Tower at this time. It would require some form of Clarketech (for the elevator) or a hyper-expensive active support system (for the tower). However, I thought it important to point out some small flaws in the presentation. First, the geostationary elevator "can" have nodes in other locations on earth. The anchor points simply need to neutralize the sheer strain by reaching a node along the main elevator that is also compensated by sending another cable down at an opposing angle. If we're talking Clarketech already, then this is basic physics once you've solved the material science. Granted, Clarketech - but still, the math is pretty solid on creating anchor points on a sphere not along the equator of that sphere. The material science is Clarketech, but the math is there. Second, a break in the cable does not mean the cable will wrap around the earth and cause untold damage. It will fall straight down the gravity well. And depending on the where the break occurs, we have several mitigation systems that could be put in place to either recover the cable as it falls or break the cable up into recoverable portions. We're talking Clarketech here, you aren't just going to let this thing fall and destroy stuff - you're going to harvest that cable as it comes down and have a new one ready to go in days while your counterweight station puts itself back into the right position and does repairs on the cable still attached. Third, LEO will likely be accessed by an Orbital Tower. Orbital Towers can be placed anywhere on earth (even if the most *useful* point is on the equator), and will have massive anchors built into the crust to distribute the mass of the tower itself and the energy involved in the active support system (or clarketech if available). The ocean/lithosphere/atmosphere is really not a big deal here compared to the other issues - the energy involved in dealing with those systems is only a small fraction of the material and energy science needed to maintain the tower under its own weight. IE- if you can build the systems to maintain such a tower you can compensate for extreme ocean depth, atmospheric turbulence, crust dynamics, and induced harmonics from any of it. Its a real problem, but its a minor problem that can be compensated for in the greater problem of the design itself. Fourth: Energy - anyone building a tower or a elevator would be an idiot to not build a system capable of harnessing the energy created by having such a massive structure moving through the earth's magnetic field. At the scales we're talking about the system has more than enough energy to power itself, and large swaths of the planet too. Especially the elevator. And if additional energy *was* needed, you'd build solar power relays and satellites as a part of the orbital infrastructure to support the elevator. This is not something that will ever be powered by conventional energy resources on the ground. It will instead be one of the primary relays via which orbital generated power is delivered to the planet. Fifth: Launching from a LEO Tower - If you shove something out a door it will fall straight down... with a bit of momentum from the shove. You have to shove harder. Being at that altitude you just need to add orbital velocity plus a bit when shoving the item out the door. Not insignificant in any way what so ever... but *much* less energy than is required to lift an object from the surface to space. A good 1/4 of a rocket's fuel is overcoming drag and the weight of that fuel to overcome that drag to get into the upper atmosphere. You have a lot less drag at 220miles than at sea level. We're talking about instead of needing a full falcon 9 you now only need a slightly larger second stage rocket. Good news though, you don't need artificial gravity on your orbital tower - should be well within human tolerance and plumbing will work as expected. No vacuum toilet. Stepping out for smoke breaks might be a bit of an issue though. :) Fifth: Realism versus aspriationalism. Earth based space elevators and orbital towers are impossible under current known science. Please note - Current known science is changing "daily". And while they are impossible on earth for now... They are *not* impossible on other bodies in the solar system. It is a function of gravity, material science, and practical physics. There are no mathematical blockers to the physics involved. There are, as of yet, no known natural laws that would prevent the discovery of materials that would be capable of this. Orbital Towers are closer to the "possible" in the near term. But "possible" does not mean achievable, practical or desirable. There are more factors than pure science and math involved. Economics, for example, is a driving motivator that will rapidly kill most projects. Infrastructure is another - in order to even begin to justify the cost of an orbital tower or space elevator, you need an infrastructure that would make such a structure not only "viable" but "essential". Final note: Infrastructure is the key to any practical human presence. It must be put in place *before* the people arrive in numbers. In fact, it is the existence of infrastructure that makes all human population centers possible. Before there are O'Neill Stations and Space Elevators, before there are Orbital Towers, Launch Loops, and other megastructures on or around earth... there will be Orbital Power Satellites, microwave beamed energy relays, massive solar collectors, automated lunar construction facilities... all because lifting anything more than humans and biomass to orbit from Earth is stupid. There will be rail guns on the moon launching packages of refined aluminum to LEO. There will be robots built from that aluminum working in orbit being directed by people running VR on earth building and constructing platforms and systems to *support* the few people that will launch up there. Long before the first mars colony is actually established, or long before the first lunar outpost boasts more than a dozen living residents... there will be tens of thousands of people working in LEO. And long before there is more than the ISS and a few small outposts in orbit, there will be automated infrastructure in place to prepare the way. People always wonder where the jet packs and flying cars are. They're here. They've been here for decades. General aviation aircraft and people playing with rocketfuel on their backs. They're not practical or ubiquitous for everyone because they do not have an infrastructure that makes them as safe as a car - which is actually pretty dubious in its safety anyway. But honestly, once the infrastructure is there? Sure, there will be flying vehicles in everyone's garages. And that's where they'll stay most of the time, because you'll walk to the corner store, ride a pedal bike to a strip mall, or drive to the shopping center because that's a lot more practical and safe. But you'll probably be doing all of it in electric vehicles - because that's the way the practicality is rolling. And as we build out orbital infrastructure - its quite likely that some or all that power might be coming from space. We're all upset the future isn't getting here as fast as we'd like. But the reality is that there's a lot of work that lives under that future that supports it. That's why "infrastructure" is the most important thing we can build. You have to put in the work to get the things you want in life. If you want a future where *most* people can live and work in space - that's a lot of work. A "lifetime" worth of work from "billions" of people. The generation that had the moon landings in their youth took for granted that this was going to be "their" future. They let it go - thinking someone else (their children) would do the work "for" them. Placed these burdens on their kids while trying to narrowly control their kids lives in ways that hobbled and hurt those kids. They didn't work with their kids, they tried to make their kids work for them. They partied. They pushed their kids to making a world that supported their older and more terrestrial needs and ignored the infrastructure. (leaded gas, pipes and paint didn't help) They sold their kids' tomorrows for their yesterday. That's a price we're paying now. Its going to be 100 years before more than a handful of people are regularly living and working in space. Not because we can't do it - because we didn't do the work to make it practical and feasible. And that's on everyone who thinks "oh, someone else will make it happen!" or "Someone else will fix my problems!" or "Someone will take care of me!" That's not the way this works. Space elevators and orbital towers are fictional because they are daydreams that ignore the work. Something like them might exist - but if they do, those structures will come far after all the hard work to get the basics in place. Remember that as you read the BS all these wannabe millionaires and billionaires spew looking for you to throw money at them for the promise of a fictional dream.
11:37 The Kurzgesagt animation shows a much higher elevation though. If the exit point is geostationary orbit, it works. I wouldn‘t necessarily call it an error.
I thought I was losing my mind. Comforting to know I was not the only one to have this thought. I think the confusion is from talking about LEO and GEO interchangably. There need to be more of a distinction in the video.
@@shanent5793 wth are you talking about? Why and how would a satellite at geostationary orbit descend to 100km perigee? It would stay in "place" unless you provide massive thrust. Also, how do you think it could "brake" above geostationary altitude with also recovering energy? Only way to brake up there is to expend fuel for thrust. You guys in this thread are "cray-cray". Kurzgesagt video is stupid. The point of space elevators is not that energy needed to only go "up". The point is that you don't have to accelerate the fuel inside the rocket ship, you can just accelerate the cabin/cargo with external forces. Also if you put satellites out in LEO this won't work. If you put them out in Geostationary altitude they will just be bunched up near your elevator. You'd still have to use their thrust to move elsewhere. It will spend less energy of course as that's the very point of the space elevator idea. But that's still doesn't make it materially feasible.
Yeah, that comment makes him sound unreasonably dismissive. Kurzgesagt know perfectly well that a space elevator has to reach geostationary orbit at 36,000 km for it to make sense. They even mention it 2 minutes later.
I do find it comical that the original poster asked Elon "why is this not possible?" The only legitimate answer he would be able to give is "how the hell should i know, that's the sort of question that is best asked of an engineer" but he'd most probably start his answer "I'm really confident that within 12-18 months..."
Nah. He'd say, "Even if we knew how to mass-produce the materials needed for a space elevator, Starship is going to be better than one." And he'd be right, for a beanstalk elevator, assuming Starship ends up half as good as its specs. Maybe he'd throw in some raving about how awesome stainless steel is.
Elon Musk IS an Engineer, a mighty fine one, not limited by the constraints that us normal humans carry around like a stone around our necks. He has zero "can't never could do nothing" cells in his DNA. He can DO, while the rest of us make excuses for NOT DOING, NOT BEING CAPABLE OF DOING. That is the only difference between him and us...we all make ten million excuses about not being able to do something difficult (pick any goal here). Yes, he is my hero, without a doubt. I try to emulate him every day.
I love it when you guys debunk space related bs, it's just warms my heart because I legit hate people promising bs or out of this world plans and ideas that have 0 chances of happening.
1. No funds are being diverted from NASA nor any other public or private organization to build a megastructure in space. 2. This is completely feasible on the moon right now with current tech.
Plus there's a very real risk of people being turned off to actual, viable projects when they've sat through decades of failed promises from Musk and the like.
@@Apistevist actually no, modern material are not strong enough. Just stop. people that think space elevators are viable the same people that imagine the earth as only being 500 miles in diameter. its a severe misunderstanding of the scales involved. here's a thought experiment, you have this "significant orbital infrastructure" in LEO and want to lower down the cable to earth. so you start dropping it down into the atmosphere...the only problem is the cable you're lowering is moving 16,000 miles per hour too fast. ever see a shuttle re-entry? the air drag alone would drag whatever is lowering the cable out of orbit unless you could produce enough thrust to not only keep that craft in orbit but also support the entire weight of the cable dragging through the atmosphere at re-entry speeds...among about 100 other problems. it's actually impossible with any known technology and will likely remain impossible.
@@JZsBFF they have a scene like that in the "Foundation" tv show, but realistically most segments would burn up and the few low enough to not burn up can be handled differently (for example with parachutes or by building it such that they drop into the ocean)
@@insu_na I'll have a peek a the series. As for safety "tricks"; we all know how eager engineers are to implement those. If such a ride ever got built I wouldn't wanna be on planet Earth when it comes down. The economic impact (pun intended) alone would be 'uge. I wonder what a millon billon tons a burning stuff would do the the atmosphere.
20:28 - it just hurts to watch Musk „lie-along“ so obviously… and it hurts even more to realize that all those mindlessly clapping seals blindly believe him 🤯
One of the biggest problems with space elevators is that they don't do nearly enough. Like, the marginal cost to orbit could be super low, but the throughput is terrible. If you want a kiloton to orbit per day, starship is way better positioned to deliver than a space elevator.
@@commonsenseskeptic that's bcz people were to busy with everything that happened man People are laid off and thanks to wars which of tax money goes to . U are doing god's work here . Whether u believe in God or not , u are doing what God gave us and what is most treasured.... Rationality
@@TucsonD1 I am sure that musk would never think of something like that. Just like he never thought about how a Robo taxi would go against his idea every one should own a Tesla.
I took a conspiracy theorist work colleague through the maths to try and convince him that no material exists with enough tensile strength Vs weight to even get close. From hemp rope to carbon fibre tube 😂. His eyes were glazed over by the end.
@@thethirdchimpanzee nothing gets even close. I don't think anything ever will exist. If it did then you just opened the door to all the other problems that were discussed in the video.
Simply coat the cable with an ablative material and shoot it with lasers to generate upward thrust so it doesn't have to carry its full weight under tension. The capsules can automatically replenish some of the coating each time they ascend. It really is that simple. Simply make sure the lasers never lose power and the coating is never depleted too much.
I think with the orbits most people hear that, in principle, launching a satellite from a space elevator means you "get it for free" but that only applies to ones released at the top, in geo sync orbit. And then, it's not very useful because you now have to put in a whole bunch of delta-V to move into whatever orbit of Earth you actually want to be in...
the orbital velocity at geostationary orbit is about 3 km/s so it is actually less than in low earth orbit. this often seems to be a bit counter-intuitive. still, the velocity of the surface of the rotating earth is only about 460 m/s so the object being raised to geostationary orbit still has to be accelerated by more than 2,5 km/s horizontally while travelling along the cable. this does not come for free, it will cause a horizontal force on the cable that is not compensated anywhere by the system, and will result in the cable "wrapping around the earth" eventually
@@Rob2 yeah I don’t quite understand this point like he talks about the people doing a space walk walk if you step out of the international space station you’ll he going 17,000 miles an hour due to inertia, so why wouldnt it be the same if you stepped out of a space elevator or you know that altitude wouldn’t you just float along because you’re already going that velocity
@@mcamp9445 For a space elevator to geostationary orbit that would work, but not for one to low earth orbit. The horizontal speed of an elevator to 500km is by far not enough to remain in orbit at that height, you would fall almost straight down.
You don't get it for free. 1) it takes energy to raise the elevator. 2) relative to the Earth, you're only moving 300 m/s on Earth's surface due to rotation, but you'll need to be going 3000 m/s in geostationary. So that's more energy needed. Nothing free about it.
The biggest problem with space elevator is that it forms a giant "lightning rod" through which the ionosphere would be constantly discharging to the ground. The potential difference there is around 300 kV. Good luck withstanding that.
Not as big a problem as you'd think. 300kV, but the impedance is huge. So high it's hard to even measure - otherwise people would just use kites to suck some of those sweet electrons up as a power source*. The current wouldn't be enough to worry about. The lightning bolts, on the other hand, those would be a problem. * This can actually be done, and there are videos on youtube of people doing it - but it generates just enough power to turn a rotor with no load and very good bearings.
You all better enjoy it since it's the only way a human will ever "experience" a space elevator. The food better be damn good because it sounds like a really expensive place to eat, knowing how Disney prices their stuff.
@@ChristopherSadlowski well the future of humanity and its technologies are yet to be written. The same thing people say about space elevators is the same thing they said about human flight, landing on the moon, the list goes on. Bunch of nay sayers. The food was great, not Michelin Star great but as good as a chain high end restaurant like Ruth Chris, Capital Grill or Roy's. Prices matched about that too. By the way there are two options to eat there you can have the dinning room or the lounge. The Dinning room gets you a table near the "windows" up close and a bigger menu, it also comes with a bigger price tag. The lounge has a smaller menu puts you up closer to the center of the room by the bar. It's also much cheaper. In the end you are paying for the atmosphere not the food. So if you just want the experience go with the lounge. Though if you have a group that is more than just a couple i strongly recommend the dinning room. Especially if your group likes to share food. Order something different for everyone and each try it. Btw best food i have ever had at disney is the Yacht Club Steak house. Thought I Haven't gone to Victoria Alberts.
Great video as always. One thing that’s always concerned me about these things aside from the points you’ve made, is the elevator being a giant target for terrorism.
I've brought this up repeatedly with people that bring up space elevators and the answers always range from "blah blah world peace through socialism will stop that" to "we can use super drones/guns/lasers/pewpewpews to kill the bad guys first"
So, I've been in the Shanghai World Finance Centre which is said to have the fastest terrestrial elevator in the World and it ascends at about 70 km/h or about 120 storeys in a minute. That was right on the cusp of uncomfortably fast as your body and brain adjust to the air pressure change from ground level. You kinda step off of it in a little daze, I think I even let out a little Keanau Reeves getting new skills uploaded in the Matrix "woah" when we got to the top. The idea of ascending 350 km in 1 minute sounds like it would pretty much liquify you.
Take a look at 22:33. No matter how massive your "counterweight" is at geostationary orbit, the counterweight will be in free fall by definition and will have zero lifting capacity. ie. it could not support a length of cotton. (If you could space walk out to any geostationary satellite, how much do you think you could pull it toward the Earth without both of you dropping from orbit?) For the orbiting mass to support a tethered cable, it must want to shoot off into space. Meaning, the counterweight must be orbiting beyond geostationary orbit at greater than free fall velocity. cheers PS. as you have alluded to, the complex dynamics of the tether would be a great problem and I expect would almost certainly destroy the whole structure in very short time.
@@shanent5793 Hi! A very good point. However, the motion of the tides does not come free. The pull of the Moon on our oceans causes tidal friction which slows the rotation of the Earth (longer days), and also causes the Moon to recede from the Earth (albeit at a very slow rate). cheers
@@TucsonD1 Hi Tucson. I agree, that's what I meant in my original post "Meaning, the counterweight must be orbiting beyond geostationary orbit at greater than free fall velocity". cheers Graham
Hyped for this video as someone intrigued by the idea of space elevators but also know they will never come to be as the material strength doesn’t exist, they would have a tendency to break and kill millions of people and destroy huge areas of earth on the ground. They’d have to be built on the equator and many thousands of kilometers above the earth. The mass needed and cost for a fever dream of a guaranteed future disaster is insane.
1. Look up terminal velocity. This would not kill millions from falling. It would have the terminal velocity of a carbon fiber rope or about 20 meters a second. This is based on the density of carbon fiber being lower and the drag higher than a human in freefall which has been clocked multiple times to be around 50 meters a second. 2. When looking at the size of the investment, it is always best to also examine the return one gets on that investment and for how long. Look at the fix and variable costs. Look at the upkeep and total cost of ownership. Yes, this would be expensive in labor, materials, and energy. You would also reduce the cost of putting something into LEO to a few hundred dollars per pound... all day long... everyday... for hundreds of years.
@@krisspkriss Good luck engineering a cable that could take the strain involved for hundreds of days, never mind years. And that's ignoring the times it will inevitably be struck by space debris. It's a pipe dream. Your ROI will be very squarely in the negative even if you can do it for free just based on legal fees from the massive lawsuits from those affected by the cable's uncontrolled return to earth.
Kim Stanley Robinson addressed many of these issues in his Mars trilogy (Red Mars, Green Mars, Blue Mars). They are a great read and answer a lot of the questions raised by this video. It is a simple fact that STEEL is not a viable option and a space elevator will require multiple cables, counter weighted transports, temperature stabilization, and an EXTREMELY deep anchor into bedrock, most likely a mountain in Ecuador.
There are some errors, it is very difficult to get these debunking videos completely correct: - the "space elevator to geostationary orbit" needs to have its "counterweight" above the orbit. The idea is that a weight higher than geostationary orbit would "pull" on the cable to keep it straight. A weight at exactly geostationary orbit would not impact any force to the cable, and would be useless. The weight of the cable would still pull it down. - when the space elevator is properly setup (with a weight above geostationary orbit), the whole thing would not come crashing down when the cable breaks. only the part of the cable below the breaking point would come crashing down. the remainder (the restaurant and the counterweight) would fly away in space, or more likely would get into a higher orbit around the earth. - the orbital velocity at geostationary orbit is about 3 km/s so it is actually less than in low earth orbit. this often seems to be a bit counter-intuitive. still, the velocity of the surface of the rotating earth is only about 460 m/s so the object being raised to geostationary orbit still has to be accelerated by more than 2,5 km/s horizontally while travelling along the cable. this does not come for free, it will cause a horizontal force on the cable that is not compensated anywhere by the system, and will result in the cable "wrapping around the earth" eventually.
Don't miss this year's annual gala ISEC convention at the Denny's next to the Des Moines, Iowa airport. This year's keynote speaker: the esteemed Bob Bigelow on integrating paranormal investigation with aerospace vaporware. Channeling Tsilkovsky.
You sound like my engineer husband who worked at the space center for a few decades while we “rode” WDW space elevator, correcting the location of the elevator, the speed, etc going up and then again coming down. :-)
If that were the case, we'd be at full blown kessler syndrome already. Much like satellites and stations do, you could minutely move your teather by nudging either the GSO counterweight, or any station along its length to avoid collisions. The end-point is fixed (if on land), but most of the collision danger comes from mid-upper LEO or above, giving you a fair amount of play. It's also likely if you had a power source that can send a climber up and down, you probably have the energy on hand for lots of tracking radars and laser ablation systems. What's a bigger hurdle is the material science, and geopolitical climate. No one would agree where to put the thing, who gets access or who pays for what portion of it, never mind the vast cost. This is kinda like worrying about a ferrari getting its windshield smashed by gravel falling off a truck when you have 35 cents to your name and will never be able to afford to buy one. :P
All spacecraft and significant satellites have meteorite-debris shielding. The chance to get hit is based on the frontal area of an object and its time in space. A tether, although narrow, has a hundred to thousands of kilometers of length giving it a huge frontal area and a guarantee to be hit. A tether to GEO would have to pass through "The Dead Zone", the graveyard of military upper stages. The only debris protection for that area is to get the heck through it as fast as you can.
@@BigfootxHunter That sheidling is to deal with particles too small to track, onces that likely wouldn't be a major threat to a tether. Stuff like flecks of paint, tiny screws, micro fragments and natural micro meteorites. And it's not like we can't remediate space junk, we'll have to do it eventually anyway; because space-dumping is going to lead to kessler syndrome if we don't start cleaning it up. If we put the money in to build an orbital elevator, putting the money in to build a 'laser broom' to de orbit all the junk left in orbit wouldn't be too hard. Also, another factor to consider, a network of orbital elevators around the planet's equator might well make all satellites obsolete. You could just cram a package onto stations placed along the theater for the same effect, and they'd be much easier to service.
@@kauske A one gram chunk of aluminium can punch a hole through a 4 inch thick piece of aluminium plate at orbital velocities. Even the small pieces are a threat to tethers. Even the tiniest debris can cut through a steel cable one strand at a time.
@@BigfootxHunter Considering a steel cable wouldn't be able to exist at that length under its own mass, that's not a concern. That's one thing people don't understand, the materials to make a tether that wouldn't snap under its own weight from surface to LEO would have strength that would reshape engineering as we know it. That's the rub to take home, and that's why the elevator will remain a material science issue, with all the other issues being comparatively tiny. Also, 1 g of aluminium would be big enough for modern radar to spot, it's around half a CM cubed. The stuff we can't track and avoid is far smaller than that. And if it can be tracked, it can be avoided, or redirected.
Another factor that gets often ignored is the radiation from the sun. The space elevator needs withstand harsh UV radiation. Furthermore the upper atmosphere also interacts with this harsh radiation. The oxygen (O2) splits into two single oxygen atoms that are highly reactive. A space elevator will probably stay in service for decades and the material need to withstand these harsh conditions. A protective layer is needed (more weight) and it needs to reapplied regularly. Carbon nanotubes may be proposed as a material. But this material seems a bit sensitive to defects in the structure. This issue may not the immediate deal breaker but it needs to be considered if they actually plan to built it.
I was walking home from the corner store listening to this video on my headphones. I literally said out loud at one point, "That's not taking into account the conservation of velocity and angular momentum!" Which might actually be the same thing now that I think about it, but my brain was getting fried listening to the apologetics of space elevators. All these dumb ideas have me so shook that I'm unable to clearly remember my terms and if I'm using them correctly or not. Oh my god...and to think people actually think something this goofy from SCIENCE FICTION can actually be done in any reasonable or practical manner.
Getting access to geostationary orbit would be useful though, there is a way to get back the angular momentum you need to rotate at geostationary by having the same mass going down. That being said, the resistance of materials will never allow that, nor the possible dramatic outcomes a giant cable wrapping around the globe could have.
I just chalk these FiSci pipe dreams as a result of The Musk Effect. The delusion that simply augmenting your imagination with impressive graphical simulations means what you are imagining is possible. Step 1: collect underpants. Step 2: ? Step 3: Mars Colony.
The CGI imagery checks out, therefore, I'm very confident that this project can be successfully completed by the end of Q4, next year. It's really not that hard! I will accept deposits *now* for your chance to be an early investor in my new, 20 year old, startup company called *Y.* (Sure, the company appears in the Yellow Pages after that X company, however, the Y company name is a more apt descriptor of our products, services and the reasons for investors putting large sums of money into our venture. And that is more profound than it sounds.) Please forgive me. I was channelling my inner pumpty dumpty. Now, all I've got to do is get my dad to quit his regular job, invest in an emerald mine and I'll have a better shot at becoming a billionaire.
Ive read a shipload of fiction which deals with space elevators. I keep on coming back to this question. Why not just pour that amount of energy and resources into an airline service to space? If you crash a few space airliners you dont lose the entire service. You crash a space elevator and you are back to the drawing board IF you can even recover.
As far as we know there’s no material that has the tensile strength to withstand the forces required to build a space elevator on the Earth (or similarly sized stellar body). You can build one on the Moon though where the gravity is just a sixth of the Earth’s and there’s no atmosphere or oceans to disturb you. Problem is that the Moon itself has no stationary orbits due to gravitational fluctuations and even if it did a selenostatonary orbit would still not exist because it would be beyond the Hill radius beyond which the Earth’s gravity would have impact. You can put the counterweight at L1 though which is stationary in respect to the Moon’s surface, but is still not stable and will require you to fire a booster to adjust the counterweight every once in a while. A proposed use for such a device is to reduce fuel costs for sending material to the Moon from Earth and from the Moon to Earth’s orbit. The problem is, however, that since there’s nothing on the Moon, such device is currently unnecessary. Until there is a viable industry on the Moon that mass produces and sends stuff on Earth in quantities that would make regular rockets inefficient, this would just be complete overkill despite being within the realm of possibility.
But, Americans are special! They're exceptional! They can do anything - other than maintain their infrastructure, supply universal health care, have a true democracy, and weigh less than 150 Kg. I can imagine what they're eating in the restaurant as they pretend they're hurtling into space...
You can't get off in LEO. You'll just fall back to Earth. Instead you'd need to get off at high enough altitude that your horizontal velocity kicks you into an eccentric orbit above the atmosphere. It would be below geosynchronous but well above LEO. I'm not sure what the minimum exit altitude would be.
Congras on a well deserved 100k... The common theme with obital elevators in media (games, movie or animation) is always in a dystopian future. E.g Ace Combat 7, Gundam 00. Lol is 22:20 a correct depiction, I thought it would have been like a metorite hitting the earth with the amount of mass.
It's probably going to be impossible to get reservations at that restaurant/attraction now. Sounds like a cool experience though. Thanks for breaking this down. Any updates on "Star Raker"?
If the station was in geostationary orbit it would already be moving at the velocity nessesary to stay in orbit so anything on the station would also be moving at that velocity and would stay in orbit. This of course doesn't apply to Leo. And also doesn't explain how the weight of the tether wouldn't pull the station down. Lot of good stuff here though
One thing I find lacking in discussions on the space elevator concept is the examinaton of forces in the equatorial plane, e.g. Coriolis force acting on an elevator cabin during travel, and what that does to the whole system. Consider this: A cabin traveling upward will experience a force tangential to the cable in the direction opposite to earth's rotation. That force _will_ tug on the cable, and eventually on the "space anchor", which _will_ result in an earthward ("anti-normal") acceleration of that "anchor". This in turn _will_ cause the "space anchor"'s orbit to become eccentric, effectively causing the anchor to oscillate in a kind of circular motion (as viewed from a ground observer) around its designated "parking spot". Such oscillations _will_ be dampened by the cable eventually, but that also means that the anchor _will_ lose energy to the cable, which _will_ convert that energy to heat. The same process, albeit in reverse, _will_ happen when the cabin travels back towards earth. The bad news is that this will _not_ recuperate the lost energy, but rather _will_ lose even more energy. You can't even counter this by having one cabin ride the elevator up and another down at the same time: By virtue of coriolis force they'll tug at the cables in opposite directions, but at different locations along the cable (except for that very brief moment when they meet each other halfway along the cable), so there will still be an increase in the cable tension and thus an increase in the downward force pulling on the anchor. Now if the "space anchor" were parked _at_ geostationary orbit, that would be game over: If it were an untethered satellite, it would just enter into a lower (and probably excentric) orbit and find new equilibrium there; but that equilibrium would require faster-than-earth angular velocity, which the tether wouldn't allow. Instead, it would decelerate the satellite even further - finding new equilibrium only resting on the surface of the earth. A more realistic "space anchor" would be parked _way_ above geostationary orbit instead, and would therefore fare slightly better. However, it still wouldn't resume its nominal position: Instead, it would settle into a lower orbit, compensating for the resulting "slack" in the cable by both shifting its partking spot further westward and also reducing the cable tension. Eventually, even this system's orbit will drop below geostationary, and things will come crashing down - literally. So yeah, even if you manage to get an "anchored satellite" contraption to actually work - as an elevator it could serve only a limited number of rides. Which quite defies the whole purpose of the concept.
Oh, and did I mention tidal forces? Yeah - we'd need to get rid of the moon first. Turns out it'll tug a "space elevator" back and forth twice a day, again causing the system to lose energy in the form of heat.
Regarding your wind turbulence suggestion, I am not entirely sure but I don't think there is any wind turbulence at the equator. If I remember correctly, there is almost no relative wind there since all wind begins there as the air is heated at the surface and flows straight up in an area known as the doldrums. When the warm air finally reaches the top of the atmosphere, it then spreads out creating wind patterns to the northern hemisphere and the southern hemisphere and the relative winds caused by the Coriolis effect. Of course this really doesn't matter in this case since the entire concept of such a structure is ridiculous.
It’s amazing how many people fail to realize that, if you step off the roof of a building that extends to the height of the ISS, you don’t go into orbit, you fall straight down.
Just realized you're at 101k subscribers now, congrats! (Totally missed you finally reaching 100k.) Super happy. Now your subscriber count won't bother me quite as much while I'm watching your videos. :D
You are absolutely right. A space elevator can only be to geostationary orbit. They need a Massive structure on a geostationary orbit with a long tail above it. The cable is impossible to make using current technology. Making one means clearing space from all satellite and debris to avoid collisions.
Not to mention Angular Momentum. The car at ground-level on the equator is travelling at 1600km/h. As it gets pulled up the cable, it will still want to travel at only 1600km/h and will tend to pull the cable backwards. This, in turn, will have the effect of reeling in the counterweight, causing its orbit to become more and more elliptical until it all comes crashing to earth. To avoid this, the car will need to be accelerated up to the orbital speed appropriate to the altitude as it climbs. Nothing is free in physics.
I am by no means a engineer but i would assume this would be impossible due to the weight of the cables alone which is a problem potentially for Jeddah Tower which is tall but is nowhere near space even carbon fibre cables like what is planned for Jeddah Tower elevator would probably still be to heavy if it went to space
People tend to believe that Sci-fi movies are all possible, do a bit of real science and most of the things they've watched are impractical or extremely improbable, like Feynman said once: “Keep an open mind - but not so open that your brain falls out.”
Great quote. I looked it up and......" the January 27, 1940 edition of the Blytheville Courier News reported that Professor Walter Kotschnig told Holyoke College students to keep their minds open: “but not so open that your brains fall out.” 1940, now that is a long time ago.
Before even watching it: how should this work when geostationary orbit is at least by an order of magnitude higher than LEO? Angular velocity would be to low for stable orbit, it'd just fall out of the sky. The anker would need to be even higher than geostationary to compensate for the additional weight between earth and anker.
@@commonsenseskeptic Yes congratulations at reaching the 100k mark of subscribers. Please keep it going because I only like the 100% truth been told. Not these lies or half truths and in some cases people living in and believing in their own bs fantasyland world as being the real deal. Again congratulations at the 100k milestone. Pete from Tasmania in Australia.
@@commonsenseskepticagain... *"NOT NEARLY AS CRAZY AS IT SEEMS"* by way of example...why land on the Moon when simply being in orbit around the Moon is an incredible achievement...and *THEN* try out the Space Elevator.
First thing that comes to mind is that the elevator seems to be in florida. Florida is not on the equator, so there's no way for a space station to be in a geosynchronous orbit above that point. Also stuff in LEO has to move much faster than the ground below to remain in Orbit. There's a reason why geosynchrnous satellites are at a ~36 000 km orbit since the orbital speed at that distance is just slow enough to move in sync with the surface below.
I'm guessing maybe if it ran the speed of an elevator in a building? There's no reason to expect it to take more than (say) 10x as long as a rocket ship, as long as we're inventing the technology for the cable.
Just a couple points: A space elevator would not need to be on the equator. Multiple lines could be run from differing location both north and south of the equator to counterbalance their off center torque. Also 220 miles could be maintains if the combined mass of the object was at orbital speed. Say a ring where half of the mass was traveling at double orbital speed. But that would fall in line with the significantly better orbital ring. 150 mile per hour wind would only produce as much force as 70 mile per hour wind a sea level.
I must have missed that Musk was going to name his point-to-point offshore platforms Phobos and Deimos - appropriately the deities of fear and panic... which is what anyone boarding a Musk point-to-point rocket would be feeling.
5:01 Their is a way to have a space elevator teather in Florida. Florida to LEO station and also Peru to the same LEO station. 6:34 Eletricity from the grid (possibly to the climber or through the cable) 7:09 Rocket comparisons are not correct. The rocket is going 20,000Km/hour horizontally across the planet not verticaly. (see the altitude at 198KM at 8 minutes) 8:38 Despite all the mistakes above (2651 (km / hour)) * 8 minutes = 353km. 8:50 : Move the station out to GSO and the point on the cable at 350KM will still be stationary. This allows you to build the station. 10:23 You are above the atmosphere which means no atmospheric drag 10:38 Possibly their is a tether connecting them to the elevator above the station and they are behind the station on the orbit. 11:08 the station is traveling at 10,800km/hour if you use the same refrence frame at 27,576km/hour for the ISS. But with the plane changes the diffrence is much more then 17,000Km/hour 14:49 : The counterweight does not put any weight on the cable. Think of it like hanging a rope from a bridge. The weight of the bridge does not change how strong the rope needs to be. 15:02 Testing for the beaming part of the elevator currently use 1km cables. (Still a lot more then the required length still) 17:11 at just 8km up the air pressure is only 30% of the ground 17:51 you do not want a lot of weight pulling at the ground as that would makes the cable required to be much stronger. Even if you only have 100 tons of force then still means you can have a 10 ton climber without pulling the anchor below GSO. 19:26 If you go the ocean anchor you do not want it to be attached to the ground. You want to be able to steer your ship around the weather. The MSC Irina for instance weights 240,000 tons fully loaded. This is a pretty good anchor. 23:00: You disconect the ground station and now the cable falls stright down and does not wrap. (Plus with how light weight the cable is , it will likely burn up in the atmosphere) 23:46 Why would the higher up of cable be in the shade. The earth's shadow is only so big. - I argue that a space elevator is more unrealistic then O'Neil cylinders and Mars Colonies. We have a pathway to them without new breakthroughs in science (only economic). We do not have a pathway to a space elevator without new breakthoughs. Space hotels with gravity also do not need new science(only economic) unlike orbital rings.
You say that this thing will attract lightening like no other system in the world? Great Scott, Marty, I think that we just solved the issue of how to power the space elevator … !😮 How many gigawatts did you say that we needed, Doc? 🚘
12:04 I may not remember this correctly but I think the kurzgesagt video was assuming a space elevator with a counter weight at geostationary orbit and some length of run even further out to allow the launch of stuff out of orbit. If the counterweight station was in geostationary orbit (and there was a material strong enough to work as an elevator cable etc etc) so kurzgesagt was saying something accurate, by definition if you are in geostationary orbit you are in orbit.
The counterweight cannot be at GEO .. has to be well beyond to keep the tether taut (via centrifugal force) or both the tether and the counterweight will fall to Earth
@@xenuno usually the models have a very heavy rock at the geostationary position so that it doesn’t get pulled around easily and a much smaller counterweight on a second tether at a higher position that can be winched up and down to keep the masses balanced and keep tension on the cable etc, it could also serve as a launching point to send stuff out of earth orbit.
@@glenecollins Ya I spose that would work but all the models prophesize tether properties and dynamics based on Unobtainium, specifying strength, density, and a host of other properties that real world materials do not and will not ever possess
This just in - SpaceX attempt a second launch of the Starship, although booster separation was successful, it _exploded_ in perhaps one of the biggest blasts I've ever seen. It gets better, mission control Boca Chica lost contact with the Starship, it exploded at suborbital altitude, and once again, just like in April, SpaceX attempt to save face by calling it "A Rapid Unscheduled Disassembly", in other words, it means it blew up again.
This also in - the test worked a sight better than the April test, and didn't do any damage to the ground. SpaceX can get another test on the platform by the end of December if the naysayers will let him. Fusilier7 doesn't seem to be one as will let him.
A one inch thick braided steel wire cable weighs roughly 2 pounds per foot. That means a cable reaching to geostationary orbit would weigh 118,080 tons. However, that same 1" thick cable will fail at 65 tons of tension. You'd need a material that's 1,800 times stronger than steel just to support it's own weight. Materials science is not yet up to the task...
10:50 Small correction, they wouldn't burn up in the atmosphere specifically because they aren't moving fast. Instead they would just fall until they reached terminal velocity and then smacked into the Earth.
I don't think you are right. They start move-less at 350km above ground ~~ 270km above 'the top of the atmosphere'. Applying just basic physics. (s=1/2*g*t*t and v=g*t), it would take them ~233s of undecelerated free fall before reaching the top of the atmosphere, reaching speed of ~2330m/s = 8400kmph or 5200mph or Mach7. I'm no expert, but entering atmosphere verically down @Mach7 WOULD pretty much cause you to burn down into a charcoal. Pretty much like Vladimir Komarov did.
There is another big problem. The rising capsule has mass which must also be accelerated at right angles to the cable, as the farther it gets from the surface, the larger a circle it''s motion will inscribe and the more rapidly it will be moving around the Earth. It will be moving faster at the terminus than it will at the Earth's surface. So, it will resist that lateral acceleration and induce a lateral force on the cable, drawing it back opposite the direction of rotation of the Earth, like a bowstring. Some sort of thrust will have to be applied to offset this, or it will massively load the cable and likely pull the counterweight down toward the Earth and/or stretch the cable. The opposite problem will be encountered on the return trip, with the capsule having to bleed off rotational velocity, again with a thruster of some sort. The amount of thrust will increase as the operational speed of the lift increases. This counter thrust will undoubtedly add to the vibrational harmonics. A smaller thruster can be used over a much longer time if the elevator is slowed down considerably, by taking a few hours or longer to make the trip.
@@shanent5793 The total amount of thrust applied is the same no matter how slowly or quickly you go. So, you have to use the same amount of reaction mass, which is enough for a round trip. The mass for the return trip adds to the amount you have to bring for the ascent, as it also needs to be accelerated to orbital speed. A slow ascent means that there will be more water, food, and waste processing capacity in the capsule. Perhaps sleeping facilities, too. if you end up spending a couple of days in the capsule, you will need a heavier capsule, to provide additional radiation shielding. Instead of a bus, it begins to look more like a train with the attendant mass increase, complexity, and energy requirements.
@@shanent5793 You are only considering the primary frequency of the cable, you have no idea of the number of harmonics which are possible and which ones would be destructive or at what amplitude you may get degradation of the materials in the cable. If it's a single crystal, that is one thing, if it's a laminate of monoatomic thick carbon matrix that would be a whole different deal. How much would it take for a meteorite or bit of space junk to nick the cable, causing a sufficient single point failure. Like opening a potato chip bag.... can't tear it until a little nick is induced and a stress raiser is caused.
@@shanent5793 The capsule needs to be accelerated laterally, as well as vertically. It needs to be going around the Earth faster when it reaches the terminus than when it left Earth, as it is inscribing a larger circle during the same amount of time. The cable can induce that by providing resistance, with the capsule deflecting the cable like a bowstring being pulled. This induces a harmonic as the cable rises with the point of resistance moving up the cable at whatever rate of rise is found to be sustainable. If the cable can't stretch, then the terminus will be pulled downward, with the maximum deflection coming near the middle of the trip.
@@shanent5793 Until you reach resonance. Then..... And that isn't my primary objection to the situation, as just varying the velocity of the capsule at random could probably dampen the harmonic resonance or the primary wave.
This wasn't mentioned either........... A long cable sweeping through lower orbit will acquire an enormous amount of electrical charge. An LEO satellite experiment to see if power could be generated ended up melting the cables. During a solar storm, the amount of electrical charge could be truly terrifying.
This video takes me back to the 80's when I first read about the idea and excitedly asked my physics teacher about it. She told me it was a daft idea, pointing out many of the problems highlighted in this video. I was a little upset that my easy trip to space wasn't to be, but at least I learned about orbital velocity!
20:08 this is actually a self propelled ship that is dynamically positioned usong theusters...and a consteuction ship that not connected to the sea floor unless they are lifting or setting something onto it with the cranes
I just witnessed another SpaceX launch failure and am so looking forward to your next video about the event. All the fanboys along with SpaceX have already begun to spin the event.
@@Albtraum_TDDC I thought the purpose of the launch was to head to space, circle the earth and land somewhere in the Pacific near Hawaii? Why did it explode? Is "ok" what they were aiming for? Did I get it wrong? If there is a "space" mission with "goals" and the goals aren't realized, do we then call the mission a "success"? Did I miss the realization of SpaceX's attempted achievements? Or, are we living in the upsidedown world where we call failures success? If this test flight had a crew onboard, would it have been considered a success? Please enlighten me.
@@QuestionEverything-qp6kw I was just asking. So it exploded after launch, but made it to orbit? Why did it explode? I thought only the stage one rocket exploded, when it was supposed to be reused after landing. Did the whole rocket explode later?
To be fair, while you can't have the bulk of your elevator sitting in LEO; physics-wise, you could have a small stop-off hanging from a bigger counterweight that is at GSO or higher. Effectively, you could put any number of stops along the cable (or cables) and they'd hang in-line with the structure as a whole. You can also put things above GSO and use them to hurl objects onto escape velocity; assuming we could find a material durable enough to work out for Earth's gravitational pull. There's probably zero chance the first elevator would ever be put out by a lone private entity though, it would be a massive, likely international undertaking if we ever unlock some sort of super material that can do the job. Also another thing to note, a singular teather is likely not a sustainable system overall anyhow; as you move mass up and down the structure, you'd have to constantly move counterweights around, esp if you are moving cargo around outside the GSO region of the structure. I imagine you'd need dozens, maybe hundreds of theaters for a system with multiple climbers and stations along its length, all with adjustable counterweights to stop the structure from going slack due to climbers moving along it, and cargo or docked craft being added, removed and repositioned.
@@commonsenseskeptic OK, that's a good point. Then how about the Norse mythology story of "Yggdrasil" the cosmic tree which connects various different realms. The trunk rises through the middle realm of Asgard, thereby connecting all the nine worlds of Norse cosmology. Now yes, Babel predates that too, but it's still an interesting historically analogous story of a space elevator.
I saw something once where they spoke about space elevators and the problems with the materials we currently have that could be used for such a device. They looked at spider web as a viable material if we could make it. It would be light enough and strong enough to hold itself together, tethered to a heavy thing in geo-sync above. Dont remember what else they spoke about.
I'm not sure if it was done yet, but there are plans to genetically modify silkworms with spider DNA to increase production to be viable enough for textiles.
@@UA-camBorkedMyOldHandle_why There are a few reasons space elevators are sci-fi, one of which is we don't yet have material(s) light, strong & flexible enough without stretching too much.
@@hanspecansmaybe exactly the way someone in 1800 would have thought pulling some little flat object out of your pocket and talking over moving pictures with someone on the other side of the globe was magic? Yeah, with enough determination and incremental scientific and engineering progress “magic” becomes an accepted element of daily life.
15:35 😳😱 GOT DaMn son, this part scared the crap out of me! I had the screen off and my headphones on listening to this episode while I was cleaning 😂 🤣
Maybe use the tether itself to generate power from the electrical potential energy difference between earth level and upper atmosphere. Satellite deployers could consist of a rotational launcher a la Spinlaunch, or maybe a railgun type linear launcher. It would still require acceleration to orbital velocity, but that should be much easier to achieve without all the atmosphere in the way. The weather and resonance from winds blowing over the tether seem like maybe the tougher nut to crack. And how much is the length going to fluctuate from thermal expansion?
Overall would likely make much more sense to look how to build autononmic, self reparing drones which mine the moon and build something out of that if possible. We overall should focus more on that before starting to look into space, beause without such technology, there isn't much we can reach up there. As soon as we got drone which can build a whole city on their own on earth, we can think about if they can do that in space. Else: what's the point even to create such a space elevator or whatever in the first place?
It's a writer's daydream and impossible for basically every reason imaginable... Or as Elon Musk would put it "90% complete and will be commercially available next year."
Hi, I work for a cutting-edge high-tech corporation. "90% complete" means that the design is not even finished and there is no design-freeze yet. Nor has it been built. Nor has it passed the absolutely brutal performance-tests that are required to test for long-term viability.
"Honestly, it's not that hard" (TM)
''This is something we can do RIGHT NOW''
Which is way more profound than it sounds.
Don't forget it would probably solve the world hunger issues. You have to make at least one promise that has nothing to do with the project too. Muskology.
To get to 21,000 km/h we will have to use a hyperloop for the tether. It should be done by the end of this year. Worst case next year.
Concerning. Looking into it.
A hyperloop?
What a brilliant idea! We already got tonnes of vacuum in space, to put into the tube!
`Honestly, its really not that difficult`
@@MyKharliand why not just forget the anchor for the tether? Just build a symmetrical system with two space elevators going from antipodes and connect the cable from one with the other through a big hole running through Earth's center. I've heard there is now a company which made boring such tunnels much cheaper as it has ever been.
@@akyhneikr, all they need to do to refresh the vacuum would be to open a door at the top and let some more in...
One potential correction if I may. The concept usually involves a cable that reaches beyond geosynchronous orbit and which is terminated above geosynchronous orbit with a counter weight. Now, if you graph the tension in the cable, the highest tension is at the point of geosynchronous orbit. The tension in the cable reduces as you move towards the ground. Which is what you expect because each point in the cable has less cable below it that it is holding up. In theory at least, when you reach the ground, the tension is zero. Of course adding a load will add to that tension, but the tension is supported by the cable from above. What I'm saying here is that although you need an anchor point, you do not need a massive anchor point since ground level is where you see the lowest tension. In fact you can actually tether this to a floating ship or floating structure of sufficient mass.
Also, the counterweight (beyond geosynchronous orbit) is actually moving faster than geosynchronous speed. If you release an object from this point, it will go into an orbit that dips above and below the orbit of the counterweight. It won't get you into escape velocity, but it will get you most of the way there. At least in theory.
Yes, its impractical with today's technology. But being the pedant I am, I figured I should correct those bits :)
You have it exactly backwards, the ground is where the greatest tension is. That's why you need to hold the cable down, if the tension was zero it would be floating.
@@PlatinumAltaria No, wrong. The greatest tension is at geostationary orbit. The cable is being pulled by the counterweight beyond geostationary orbit and below geostationary orbit the cable hangs. I know its counter intuitive to some, but that's the actual physics. Now, you do need to apply some additional tension to the cable to keep it reasonably straight against other forces and that additional force needs to be resisted by the ground, but that's a small force compared to the cables own self loading. A few tens of thousands of tonnes (a big ship) is sufficient to this task.
Think about it. You have a fixed point in geostationary orbit. You lower a cable from there. Every km you pay out is additional mass that has to be supported by the cable above it. Hence the tension rises the further you go up.
Not pedantic at all, that's the actual design and anything else is a sci fi misunderstanding of the engineering concept.
3:24 Okay I actually laughed out loud at this reveal, after marveling at how long it would have taken me to find the location on Google Earth and then wondering why they chose Disney of all places.
Thank you for including the process even though you could have skipped it!
Anyway. Arthur C Clarke has already specified (sort of!) where one of the few viable places on earth to build it, is. He suggested Adam's Peak /Sri Pada in Sri Lanka due to its proximity to the equator.
In fairness, tech to make space elevators is a lot closer to current tech than ressurecting cryopreserved humans.
Or, to colonizing Mars.
@@backalleycqc4790 Honestly that kind of depends on how you define Colonising. If it means making a limitted permanent pressence on Mars that does seem possible with current tech. It would require a genuine protracted effort but a small permanent research station like the ones in Antarctica (granted it would be a lot hard and would likely take a couple decades to achieve) it is not out of the realm of possibility of current technology.
But if you mean a proper civilian colony on Mars working then yes I 100%.
I remember very well that in 1969, when the first man set his foot on the Moon, NASA projected the year 1986 as an option to do the same on Mars.
@@mittelwelle_531_khz With the budged they had at that moment in time they could have done it.
@@mittelwelle_531_khz They could have but the political climate as well as a differing technological pathway pulled the resources away to more important projects.
You raise good points but we can't skip on the opportunity to build the largest yo-yo in the universe!
We really should combine this with SpinLaunch technology, spinning out the tether on demand!
Hereby, I give the world the Space Chameleon, AKA, the HyperLick - it's that easy, really.
Largest yoyo in the universe *as far as we know*
@@UCXEO5L8xnaMJhtUsuNXhlmQ we're the only ones dumb enough to actually do it
We don't have the largest yo-yo, just millions of smaller ones walking around. Ba-doom-dish.
A space elevator makes Hyperloop look entirely practical and sensible in comparison. And Hyperloop is totally impractical.
Subscriber to you as well as this channel.
This video did a great job of specifying LEO in the title. Which anyone who has taken a simple orbital mechanical class knows is impossible.
A space elevator ONLY makes sense for deep space (IE, higher than geo stationary) destinations.
Yes, we currently don't have materials strong enough to handle going from ground to geostationary. Simple as.
But if we could somehow lift things past geostationary orbit, it would be amazing for getting payloads into deep space.
Hyperloop is impractical because the tube has to be in vacuum, right? There is plenty of vacuum above 100,000 feet.
Now lets talk about electrifying the cable. You now have a very long rail gun or maglev track if you prefer.
I agree that the cable anchor has to be at the equator but the terminus has to be at geosynchronous orbit with a big counterweight. If you need to have satellites at LEO, I would think it would be possible to build way stations anywhere along the length of the cable.
Lastly, any cable strong enough to support it self and facilities and the counterweight, should be able to withstand space debris hitting it. It seems like you have a very narrow cross section so that most space junk would miss it.
Space Escalator. I'm telling you, guys.
Not region Locked. Makes it's own electricity. Creates and controls weather patterns. Cools the planet. Launch platform is Already moving at speed, just let go.
If i remove all my knowledge about physics that sounds reasonable
read that with an Elon Musk voice, stutters and all... hilarious
The stairs will be made out of solar panels, and it will have wind turbines.
@@fredlaroche6969 I Don't Stutter, but my partial gives me a lisp sometimes.
@@tomlxyz Not physics, it's engineering.
A simple 3:12 ratio ramp. 14% grade, 25 degree angle, OSHA standard.
Musky, "...why can't this be done?" LOVE IT. You guys are legends.
Arthur C Clarke made space elevators seem so reasonable in The Fountains of Paradise.
Clarke wouldn't be surprised to learn how far carbon nanostructures have come since his day. The space elevator is within our reach. He'd be proud.
I always assume the topic of space elevators for scientists is just a thought experiment in the absurd to get the mind thinking about things. Kind of like when someone in disaster preparedness thinks about how to prepare for a zombie apocalypse. You don't actually think it can happen, but what are the types of problems you would face, and how could you potentially solve them.
We seem to do this sort of thing a lot in tech. We imagine an absurd way to solve a problem of we had an unlimited budget. But sometimes, that brain storming picks up on an idea of part of it that simplifies and works for the actual problem we were trying to solve.
Space elevators were a semi serious proposal for how to lower launch cost, the basic idea being that rockets spend a lot of their energy just carrying fuel and fighting air resistance. A space elevator would just be fed energy continously so it doesn't need to carry it's fuel and it could move slowly enough where air resistance isn't an issue, you could even just have it inside a depressurized tube. Then once you get to the desired height you could simply just launch the payload into orbit using something like a mass driver. This is basically the same idea that's behind all forms of space infrastructure. The issue with space elevators were many, firstly they're huge and have to be built at the equator, the cables need to be unnaturally strong, actually delivering power to the crawler is really difficult, and if the cable snaps it'd whiplash around the equator in the single biggest industrial disaster ever. However as you mention it is sorta like preparing for a zombie apocalypse in that by thinking out this scenario you learn what you actually want. A space elevator is like the best possible space infrastructure you can imagine, short of magic like teleportation there is no possible way to make it cheaper to launch things into space. So every other form of space infrastructure tries to approach all of the upsides of a space elevator while negating the negatives, space tethers are one example of much more realistic space infrastructure that actual companies have done research into, reuseable rockets are another idea.
Once it exists, it'd be great because you could lower the cost of getting materials to space, but more importantly, increase the frequency of such trips, *but* no materials exists that can do such a thing and by the time we have it, we'd probably have just gotten to other planets with rockets anyway.
Nothing wrong with the thought itself. I quite like that humans come up with ideas like this, it’s nice to challenge the idea too.
@sedalionthunder6295 the problem isn't the idea, the thought experiment, or the pretty cool looking restaurant at Disney. The problem is turning the idea into a con and taking money from hopeful people.
Ha I was going to say the same thing.
Isaac Arthurs channel did some really good discussions on space elevators and an orbital ring as means of getting payloads into orbit more easily. And yes, its a long way from being even remotely practical.
Isaac has some really good content and does a great job pointing out the realistic, hypothetical, and scifi parts of his discussions. Ive been watching him for years.
Couldn't help imagining several thousand kilometers of thick cable falling through the atmosphere, directly above. Like many dangerous things, it looked really cool.
It would likely snap back into space
Check out the show Foundation. Their space elevator falls onto earth. Pretty cool.
@@anno5936it's long enough to be stable, if it breaks it's no longer stable
@@anno5936what? The part above the break might do this depending on the forces to that lead to the break, everything else is coming down because it does not have enough perpendicular speed to overcome the gravitational pull.
Halo 3: ODST actually shows you what a space elevator "collapse" would look like. When the New Mombasa tether finally gives way, it gets yanked into orbit by the centrifugal forces of the counterweight, dropping bits of support structure as it flies away.
As always, it's a lot easier to make a CGI video than actually work through the engineering challenges.
I have met plenty of 'idea guys' in my career. They throw out impossible or near impossible concepts and then get frustrated and angry when engineers tell them why it's not going to work.
damn architects
Engineering challenges were worked out well over a decade ago.
It's not even that expensive.
Is just an idea that sounds so crazy nobody is willing to actually take it seriously.
First of all you use Rotating Space Elevators (RSEs from now on).
Imagine a wheel traveling along the ground. If your car is going 20 freedom units per hour, then your wheels are going from standing still to going 40 freedom units, in a sine wave.
Now make that wheel double the length of low earth orbit. Now get rid of the wheel and just make it a ribbon about 3 ft wide and a couple of micro freedoms thick.
Every time it goes around when it hits the bottom it will be stopped. All you need is a hook on the end.
By having adjustable mass at the center station, weight going down, cancels out weight going up.
So assuming some sort of peerage agreement is worked out, that's a "free" ride to orbit.
You can increase or decrease the amount of tethers arbitrarily, so scaling is easy that way.
And you can put them in progressively higher orbits.
That also means you can use them for deceleration. Meaning faster transit times, and getting paid for extra momentum.
Does a bunch of other cool stuff.
Does it take any unobtainium. I'm pretty sure according to the math, regular kevlar would work.
@@jtjames79 Nothing you said was true, Mr Idea Guy. The engineering challenges have NOT been worked out and no material in existence now or even prophesized in the future is up to the task. You've been watching too many Pop Sci channels apparently or ... your comment was all in jest
You may be surprised to learn that real engineers are working on space elevator designs right now. People who know what the real-world challenges are.
I think that orbital rings, Mars colonies, and O'Neill cylinders are reasonable. To make in 2500. Space Elevators are their own kind of difficult though. I could see us building them, again in hundreds of years, but they just don't seem practical around Earth.
And the maintenance of an orbital ring would be... quite the problem. It's the sort of thing where world peace would help a lot.
Orbital ring maintenance is only hard if you are building a single ring. You want to build several rotor/stator pairs and can shut them off in turns to do maintenance.
Space elevators might be useful on smaller bodies in the solar system like moons or asteroids.
Space elevators are just so much worse than orbital rings for Earth orbit, that they're not in the same category as orbital rings. But yeah, maintaining a maglev train 40 000 km long is going to be a bit of work.
I think they could be made before then, but we have to be in space and have worked out the whole "fuel supply to bring in asteroids for materials" thing.
The thing known in tabloid level media as the "O'Neill cylinder" wasn't ever proposed as a realistic thing, but was only ever an illustration of the sort of scale of things that modern realistic engineering might do.
O'Neill said it's probably not workable (we know it isn't) and is about as realistic to the people 80 years after the first generation small habitats are done, would build when they need a place for millions of people, as what "futurists" in the 1890s thought that the year 2000 would be like.
Scale your expectations back to O'Neill's "Island One" 800 meter diameter habitat, or the NASA Ames "Stanford Torus" 800 meter radius, and it's entirely do-able.
The '70s NASA Ames space settlement studies found that no new inventions are needed to mine asteroids and moons and to build for virtually Earth-like conditions anywhere in space where there are or to which we bring materials.
The first habitat for 10k workers, along with all the ground, launch, and in-space infrastructure to reproduce it or to build Solar power satellites would have been done by 2010. The cost would have been like many other large infrastructure or industrial developments down here. Like the Interstate Highway System, or like ≈4 of our CVNs and their air wings & escorts and the logistics infrastructure to deploy them. Far less than a small oil war or the bailouts we've seen. Less than what they projected that we'd need to spend to meet new electrical grid power in the same time frame (and we've spent far more than they projected).
Eventually when space manufacturing of very large structures is built up and they need the living space, the largest pressure vessel that we could build with then-known technology to spin for 1 G and hold shielding and everything inside, was ≈30 km diameter, by maybe half as much in length (drum shape, instead of cylinder). Concrete & steel. No nanotech self-replicating 3D printing of magically huge amounts of graphene, required.
With titanium (which isn't rare out there) instead of steel, maybe twice as big.
Any who disagree with this is invited to show their qualifications in mining, construction and astronautical engineering and where they've published under peer-review saying that those studies were wrong.
Note that before the first hab for the workers is done, the effort has paid back and ended all questions of budget or cost, with NEA metals. All objections against NEA mining of previously rare or precious or monetary metals brought back to Earth markets boils down to the lead time and scale of the effort. Yes, it's 25 years away, for NEA mining or Solar power sats to return anything big.
It's been 25 years away since the '70s.
As for a Mars colony (which is a place where people will retire and raise children): Prove that we can live long-term and stay healthy in low G. That's "proof", not S.F., not wishes and hopes that the question goes away and try it and see. Not maybe in the future biomechanically altering ourselves and our offspring.
Prove that first, and we can go on to talk about why O'Neill/Kalpana/Stanford Torus habitats in space are still the better or only option for long-term, large-scale habitation off-Earth.
As a lawyer, is it wrong for me to admit that I kind of want to hear a talk on the legal implications of building a space elevator?
OceanGate vibes, am i rite?
This would be a good talk 😊 and an interesting topic as space and law are quite a new field
Sticking it in a spot it would fall over the ocean and including explosive charges to cut it at a point that limits how much cable falls you could limit risk solely to your own country. Obstructing so many orbits is some thing else though.
Is murder legal in space? Asking for a friend.
@@johnwinter2252Murder is legal at any point over 150,000 feet altitude. Just don't ask me how I know.
In sci fi I’ve read the elevators can take days to get to altitude. In K Stanley Robinsons 2312 the elevator riders enjoy their ride time by learning parts for a space opera and performing in a grand theatre. The elevator is like a large hotel.
36,000 km / 1 day is only 1,500kph.
We have rockets that are faster.
That's really the idea, rockets need to go fast to get anywhere and this means they have to deal with a lot of air resistance. A space elevator could go as slow as it wants and therefore not a lot of energy would be lost to air resistance.
@@hedgehog3180 also no g force if it goes slow. the space elevator in fiction is either bulk cargo at slow speeds or luxury passenger service
Vaporware company: We've solved the science of space elevators.
CSS: How?
Vaporware company: Step one involves making billions of dollars vaporize.
CSS: So magic then?
Vaporware company: Ta-Da!!
At college there was a lift (elevator) to the 6th floor. I never felt quite safe in it. On the plus side, the lift was surrounded by breathable air.
I'd be wary of a lift described as _"surrounded_ by breathable air", too. Especially when it's beans day.
You are correct about the tech not existing for an Elevator or Orbital Tower at this time. It would require some form of Clarketech (for the elevator) or a hyper-expensive active support system (for the tower). However, I thought it important to point out some small flaws in the presentation.
First, the geostationary elevator "can" have nodes in other locations on earth. The anchor points simply need to neutralize the sheer strain by reaching a node along the main elevator that is also compensated by sending another cable down at an opposing angle. If we're talking Clarketech already, then this is basic physics once you've solved the material science. Granted, Clarketech - but still, the math is pretty solid on creating anchor points on a sphere not along the equator of that sphere. The material science is Clarketech, but the math is there.
Second, a break in the cable does not mean the cable will wrap around the earth and cause untold damage. It will fall straight down the gravity well. And depending on the where the break occurs, we have several mitigation systems that could be put in place to either recover the cable as it falls or break the cable up into recoverable portions. We're talking Clarketech here, you aren't just going to let this thing fall and destroy stuff - you're going to harvest that cable as it comes down and have a new one ready to go in days while your counterweight station puts itself back into the right position and does repairs on the cable still attached.
Third, LEO will likely be accessed by an Orbital Tower. Orbital Towers can be placed anywhere on earth (even if the most *useful* point is on the equator), and will have massive anchors built into the crust to distribute the mass of the tower itself and the energy involved in the active support system (or clarketech if available). The ocean/lithosphere/atmosphere is really not a big deal here compared to the other issues - the energy involved in dealing with those systems is only a small fraction of the material and energy science needed to maintain the tower under its own weight. IE- if you can build the systems to maintain such a tower you can compensate for extreme ocean depth, atmospheric turbulence, crust dynamics, and induced harmonics from any of it. Its a real problem, but its a minor problem that can be compensated for in the greater problem of the design itself.
Fourth: Energy - anyone building a tower or a elevator would be an idiot to not build a system capable of harnessing the energy created by having such a massive structure moving through the earth's magnetic field. At the scales we're talking about the system has more than enough energy to power itself, and large swaths of the planet too. Especially the elevator. And if additional energy *was* needed, you'd build solar power relays and satellites as a part of the orbital infrastructure to support the elevator. This is not something that will ever be powered by conventional energy resources on the ground. It will instead be one of the primary relays via which orbital generated power is delivered to the planet.
Fifth: Launching from a LEO Tower - If you shove something out a door it will fall straight down... with a bit of momentum from the shove. You have to shove harder. Being at that altitude you just need to add orbital velocity plus a bit when shoving the item out the door. Not insignificant in any way what so ever... but *much* less energy than is required to lift an object from the surface to space. A good 1/4 of a rocket's fuel is overcoming drag and the weight of that fuel to overcome that drag to get into the upper atmosphere. You have a lot less drag at 220miles than at sea level. We're talking about instead of needing a full falcon 9 you now only need a slightly larger second stage rocket. Good news though, you don't need artificial gravity on your orbital tower - should be well within human tolerance and plumbing will work as expected. No vacuum toilet. Stepping out for smoke breaks might be a bit of an issue though. :)
Fifth: Realism versus aspriationalism. Earth based space elevators and orbital towers are impossible under current known science. Please note - Current known science is changing "daily". And while they are impossible on earth for now... They are *not* impossible on other bodies in the solar system. It is a function of gravity, material science, and practical physics. There are no mathematical blockers to the physics involved. There are, as of yet, no known natural laws that would prevent the discovery of materials that would be capable of this. Orbital Towers are closer to the "possible" in the near term. But "possible" does not mean achievable, practical or desirable. There are more factors than pure science and math involved. Economics, for example, is a driving motivator that will rapidly kill most projects. Infrastructure is another - in order to even begin to justify the cost of an orbital tower or space elevator, you need an infrastructure that would make such a structure not only "viable" but "essential".
Final note: Infrastructure is the key to any practical human presence. It must be put in place *before* the people arrive in numbers. In fact, it is the existence of infrastructure that makes all human population centers possible. Before there are O'Neill Stations and Space Elevators, before there are Orbital Towers, Launch Loops, and other megastructures on or around earth... there will be Orbital Power Satellites, microwave beamed energy relays, massive solar collectors, automated lunar construction facilities... all because lifting anything more than humans and biomass to orbit from Earth is stupid. There will be rail guns on the moon launching packages of refined aluminum to LEO. There will be robots built from that aluminum working in orbit being directed by people running VR on earth building and constructing platforms and systems to *support* the few people that will launch up there. Long before the first mars colony is actually established, or long before the first lunar outpost boasts more than a dozen living residents... there will be tens of thousands of people working in LEO. And long before there is more than the ISS and a few small outposts in orbit, there will be automated infrastructure in place to prepare the way.
People always wonder where the jet packs and flying cars are. They're here. They've been here for decades. General aviation aircraft and people playing with rocketfuel on their backs. They're not practical or ubiquitous for everyone because they do not have an infrastructure that makes them as safe as a car - which is actually pretty dubious in its safety anyway. But honestly, once the infrastructure is there? Sure, there will be flying vehicles in everyone's garages. And that's where they'll stay most of the time, because you'll walk to the corner store, ride a pedal bike to a strip mall, or drive to the shopping center because that's a lot more practical and safe. But you'll probably be doing all of it in electric vehicles - because that's the way the practicality is rolling. And as we build out orbital infrastructure - its quite likely that some or all that power might be coming from space.
We're all upset the future isn't getting here as fast as we'd like. But the reality is that there's a lot of work that lives under that future that supports it. That's why "infrastructure" is the most important thing we can build. You have to put in the work to get the things you want in life. If you want a future where *most* people can live and work in space - that's a lot of work. A "lifetime" worth of work from "billions" of people. The generation that had the moon landings in their youth took for granted that this was going to be "their" future. They let it go - thinking someone else (their children) would do the work "for" them. Placed these burdens on their kids while trying to narrowly control their kids lives in ways that hobbled and hurt those kids. They didn't work with their kids, they tried to make their kids work for them. They partied. They pushed their kids to making a world that supported their older and more terrestrial needs and ignored the infrastructure. (leaded gas, pipes and paint didn't help) They sold their kids' tomorrows for their yesterday. That's a price we're paying now. Its going to be 100 years before more than a handful of people are regularly living and working in space. Not because we can't do it - because we didn't do the work to make it practical and feasible. And that's on everyone who thinks "oh, someone else will make it happen!" or "Someone else will fix my problems!" or "Someone will take care of me!" That's not the way this works. Space elevators and orbital towers are fictional because they are daydreams that ignore the work. Something like them might exist - but if they do, those structures will come far after all the hard work to get the basics in place. Remember that as you read the BS all these wannabe millionaires and billionaires spew looking for you to throw money at them for the promise of a fictional dream.
11:37 The Kurzgesagt animation shows a much higher elevation though. If the exit point is geostationary orbit, it works. I wouldn‘t necessarily call it an error.
Yep, totally right and this comment needs to be upvoted. I hope CSS can correct.
I thought I was losing my mind. Comforting to know I was not the only one to have this thought. I think the confusion is from talking about LEO and GEO interchangably. There need to be more of a distinction in the video.
@@shanent5793 wth are you talking about? Why and how would a satellite at geostationary orbit descend to 100km perigee? It would stay in "place" unless you provide massive thrust.
Also, how do you think it could "brake" above geostationary altitude with also recovering energy? Only way to brake up there is to expend fuel for thrust.
You guys in this thread are "cray-cray". Kurzgesagt video is stupid. The point of space elevators is not that energy needed to only go "up". The point is that you don't have to accelerate the fuel inside the rocket ship, you can just accelerate the cabin/cargo with external forces.
Also if you put satellites out in LEO this won't work. If you put them out in Geostationary altitude they will just be bunched up near your elevator. You'd still have to use their thrust to move elsewhere. It will spend less energy of course as that's the very point of the space elevator idea. But that's still doesn't make it materially feasible.
Yeah, that comment makes him sound unreasonably dismissive. Kurzgesagt know perfectly well that a space elevator has to reach geostationary orbit at 36,000 km for it to make sense. They even mention it 2 minutes later.
I do find it comical that the original poster asked Elon "why is this not possible?" The only legitimate answer he would be able to give is "how the hell should i know, that's the sort of question that is best asked of an engineer" but he'd most probably start his answer "I'm really confident that within 12-18 months..."
Well...um...mumble....mumble.... prototype....mumble ready.....already made 2 last week...mumble...mumble...
@@justinfowler2857that's something we can do ri ght now
Nah. He'd say, "Even if we knew how to mass-produce the materials needed for a space elevator, Starship is going to be better than one." And he'd be right, for a beanstalk elevator, assuming Starship ends up half as good as its specs. Maybe he'd throw in some raving about how awesome stainless steel is.
Elon Musk IS an Engineer, a mighty fine one, not limited by the constraints that us normal humans carry around like a stone around our necks. He has zero "can't never could do nothing" cells in his DNA. He can DO, while the rest of us make excuses for NOT DOING, NOT BEING CAPABLE OF DOING. That is the only difference between him and us...we all make ten million excuses about not being able to do something difficult (pick any goal here). Yes, he is my hero, without a doubt. I try to emulate him every day.
@@timcash8713 your positivity is admirable. but hes a fraud who lives by a hype and never archieved anything he advertised.
I loved the Ace Combat space elevator's inclusion
I love it when you guys debunk space related bs, it's just warms my heart because I legit hate people promising bs or out of this world plans and ideas that have 0 chances of happening.
1. No funds are being diverted from NASA nor any other public or private organization to build a megastructure in space.
2. This is completely feasible on the moon right now with current tech.
Man will never fly.
The handheld computers i saw in Star Trek as a kid were out of this world.
Plus there's a very real risk of people being turned off to actual, viable projects when they've sat through decades of failed promises from Musk and the like.
@@Apistevist actually no, modern material are not strong enough. Just stop.
people that think space elevators are viable the same people that imagine the earth as only being 500 miles in diameter. its a severe misunderstanding of the scales involved.
here's a thought experiment, you have this "significant orbital infrastructure" in LEO and want to lower down the cable to earth. so you start dropping it down into the atmosphere...the only problem is the cable you're lowering is moving 16,000 miles per hour too fast. ever see a shuttle re-entry? the air drag alone would drag whatever is lowering the cable out of orbit unless you could produce enough thrust to not only keep that craft in orbit but also support the entire weight of the cable dragging through the atmosphere at re-entry speeds...among about 100 other problems. it's actually impossible with any known technology and will likely remain impossible.
Now imagine that cable re-entering the atmosphere. Disaster! Good one, as always.
That would make a crappy disaster movie.
Well we've still got star shit and star sling to look forward too.
Exactly! Nothing has ever burned up when entering earth's atmosphere at high velocity
@@insu_na Surely a 40,000 km hundred billon ton stilt lashing Earth must be a scene in some videogame.
@@JZsBFF they have a scene like that in the "Foundation" tv show, but realistically most segments would burn up and the few low enough to not burn up can be handled differently (for example with parachutes or by building it such that they drop into the ocean)
@@insu_na I'll have a peek a the series. As for safety "tricks"; we all know how eager engineers are to implement those. If such a ride ever got built I wouldn't wanna be on planet Earth when it comes down. The economic impact (pun intended) alone would be 'uge. I wonder what a millon billon tons a burning stuff would do the the atmosphere.
20:28 - it just hurts to watch Musk „lie-along“ so obviously… and it hurts even more to realize that all those mindlessly clapping seals blindly believe him 🤯
Let's hope Musk doesn't hear of this.He may decide to 'revolutionise' elevators. Just like he did with tunnels...
One of the biggest problems with space elevators is that they don't do nearly enough. Like, the marginal cost to orbit could be super low, but the throughput is terrible. If you want a kiloton to orbit per day, starship is way better positioned to deliver than a space elevator.
Elon Musk Space Elevator: 23 stories tall and made of rusted junk, covered in RGB.
elevator you meant "space riser 420"
Congrats on 100k guys. It's been a long arduous journey through ignorance and nonsense but you made it!
The last 1000 took FOREVER :)
@@commonsenseskeptic thats because we are no bots :X
@audiogarden21 - unfortunately it's only a small fraction of the subscribers for openly fascist pro-Musk fan sites like the Elon Musk Fan Zone...
@@commonsenseskeptic that's bcz people were to busy with everything that happened man
People are laid off and thanks to wars which of tax money goes to .
U are doing god's work here . Whether u believe in God or not , u are doing what God gave us and what is most treasured.... Rationality
It must be pretty impossible if even Musk isn't claiming it's ready for production next year.
You do realize that a space elevator is a direct competitor to Musk's SpaceX company?
@@TucsonD1 I am sure that musk would never think of something like that. Just like he never thought about how a Robo taxi would go against his idea every one should own a Tesla.
I took a conspiracy theorist work colleague through the maths to try and convince him that no material exists with enough tensile strength Vs weight to even get close.
From hemp rope to carbon fibre tube 😂.
His eyes were glazed over by the end.
Now try it with the Hypersonic skyhook.
No material(s) exist...yet.
@@thethirdchimpanzee nothing gets even close.
I don't think anything ever will exist.
If it did then you just opened the door to all the other problems that were discussed in the video.
I can do it with some 80 pound test line and some beer cans. Cheers mate.
Simply coat the cable with an ablative material and shoot it with lasers to generate upward thrust so it doesn't have to carry its full weight under tension. The capsules can automatically replenish some of the coating each time they ascend. It really is that simple. Simply make sure the lasers never lose power and the coating is never depleted too much.
I think with the orbits most people hear that, in principle, launching a satellite from a space elevator means you "get it for free" but that only applies to ones released at the top, in geo sync orbit. And then, it's not very useful because you now have to put in a whole bunch of delta-V to move into whatever orbit of Earth you actually want to be in...
Free? Not even then, you won't get any angular momenum for free anywhere in this universe....
the orbital velocity at geostationary orbit is about 3 km/s so it is actually less than in low earth orbit. this often seems to be a bit counter-intuitive. still, the velocity of the surface of the rotating earth is only about 460 m/s so the object being raised to geostationary orbit still has to be accelerated by more than 2,5 km/s horizontally while travelling along the cable. this does not come for free, it will cause a horizontal force on the cable that is not compensated anywhere by the system, and will result in the cable "wrapping around the earth" eventually
@@Rob2 yeah I don’t quite understand this point like he talks about the people doing a space walk walk if you step out of the international space station you’ll he going 17,000 miles an hour due to inertia, so why wouldnt it be the same if you stepped out of a space elevator or you know that altitude wouldn’t you just float along because you’re already going that velocity
@@mcamp9445 For a space elevator to geostationary orbit that would work, but not for one to low earth orbit. The horizontal speed of an elevator to 500km is by far not enough to remain in orbit at that height, you would fall almost straight down.
You don't get it for free. 1) it takes energy to raise the elevator. 2) relative to the Earth, you're only moving 300 m/s on Earth's surface due to rotation, but you'll need to be going 3000 m/s in geostationary. So that's more energy needed.
Nothing free about it.
Just had a morbid thought where the tether snaps, eviscerates everything in its path, then leaves a mile deep gouge in the Earth.
The biggest problem with space elevator is that it forms a giant "lightning rod" through which the ionosphere would be constantly discharging to the ground. The potential difference there is around 300 kV. Good luck withstanding that.
Not as big a problem as you'd think. 300kV, but the impedance is huge. So high it's hard to even measure - otherwise people would just use kites to suck some of those sweet electrons up as a power source*. The current wouldn't be enough to worry about. The lightning bolts, on the other hand, those would be a problem.
* This can actually be done, and there are videos on youtube of people doing it - but it generates just enough power to turn a rotor with no load and very good bearings.
Been to space 220 at disney world. It is honestly amazing to actually experience this in person.
I'd love to take my kids there. If we ever go to Disney World we will make sure to visit that restaurant!
It really looks like a fun experience
You all better enjoy it since it's the only way a human will ever "experience" a space elevator. The food better be damn good because it sounds like a really expensive place to eat, knowing how Disney prices their stuff.
@@ChristopherSadlowski well the future of humanity and its technologies are yet to be written. The same thing people say about space elevators is the same thing they said about human flight, landing on the moon, the list goes on. Bunch of nay sayers.
The food was great, not Michelin Star great but as good as a chain high end restaurant like Ruth Chris, Capital Grill or Roy's. Prices matched about that too. By the way there are two options to eat there you can have the dinning room or the lounge. The Dinning room gets you a table near the "windows" up close and a bigger menu, it also comes with a bigger price tag. The lounge has a smaller menu puts you up closer to the center of the room by the bar. It's also much cheaper. In the end you are paying for the atmosphere not the food.
So if you just want the experience go with the lounge. Though if you have a group that is more than just a couple i strongly recommend the dinning room. Especially if your group likes to share food. Order something different for everyone and each try it.
Btw best food i have ever had at disney is the Yacht Club Steak house. Thought I Haven't gone to Victoria Alberts.
Great video as always. One thing that’s always concerned me about these things aside from the points you’ve made, is the elevator being a giant target for terrorism.
The elevator is basically a Michael Bay movie waiting to happen…
I've brought this up repeatedly with people that bring up space elevators and the answers always range from "blah blah world peace through socialism will stop that" to "we can use super drones/guns/lasers/pewpewpews to kill the bad guys first"
I laughed a little too hard at the "flaming meatball" bit. Thanks for that.
So, I've been in the Shanghai World Finance Centre which is said to have the fastest terrestrial elevator in the World and it ascends at about 70 km/h or about 120 storeys in a minute. That was right on the cusp of uncomfortably fast as your body and brain adjust to the air pressure change from ground level. You kinda step off of it in a little daze, I think I even let out a little Keanau Reeves getting new skills uploaded in the Matrix "woah" when we got to the top. The idea of ascending 350 km in 1 minute sounds like it would pretty much liquify you.
@ChrisRaynorMD should do a video on all the ways 40G acceleration/deceleration would kill you!
Ask yourself if you could imagine sitting in any vehicle transporting you 350 km within one minute and I think you have the answer 😀
@@StefanReich350 km in an hour would be pretty exciting. And unlikely.
@@BrySmi No, it would be a very slow commercial airliner.
@@BrySmiwe literally have trains that go that fast...
Take a look at 22:33. No matter how massive your "counterweight" is at geostationary orbit, the counterweight will be in free fall by definition and will have zero lifting capacity. ie. it could not support a length of cotton. (If you could space walk out to any geostationary satellite, how much do you think you could pull it toward the Earth without both of you dropping from orbit?)
For the orbiting mass to support a tethered cable, it must want to shoot off into space. Meaning, the counterweight must be orbiting beyond geostationary orbit at greater than free fall velocity. cheers
PS. as you have alluded to, the complex dynamics of the tether would be a great problem and I expect would almost certainly destroy the whole structure in very short time.
@@shanent5793 Hi! A very good point. However, the motion of the tides does not come free. The pull of the Moon on our oceans causes tidal friction which slows the rotation of the Earth (longer days), and also causes the Moon to recede from the Earth (albeit at a very slow rate). cheers
The counterweight in a proper space elevator design is not at GEO, it is *above* it, where centrifugal force is greater than gravity.
@@TucsonD1 Hi Tucson. I agree, that's what I meant in my original post "Meaning, the counterweight must be orbiting beyond geostationary orbit at greater than free fall velocity". cheers Graham
@@gjpercy which proves the point that a counterweight is what holds the tether taut. The video assumed the counterweight was AT GEO, which is wrong.
Hyped for this video as someone intrigued by the idea of space elevators but also know they will never come to be as the material strength doesn’t exist, they would have a tendency to break and kill millions of people and destroy huge areas of earth on the ground. They’d have to be built on the equator and many thousands of kilometers above the earth. The mass needed and cost for a fever dream of a guaranteed future disaster is insane.
As Arthur C. Clarke put it, it'll be built about 50 years after people stop laughing.
You have a cool @
Probably not millions
1. Look up terminal velocity. This would not kill millions from falling. It would have the terminal velocity of a carbon fiber rope or about 20 meters a second. This is based on the density of carbon fiber being lower and the drag higher than a human in freefall which has been clocked multiple times to be around 50 meters a second.
2. When looking at the size of the investment, it is always best to also examine the return one gets on that investment and for how long. Look at the fix and variable costs. Look at the upkeep and total cost of ownership. Yes, this would be expensive in labor, materials, and energy. You would also reduce the cost of putting something into LEO to a few hundred dollars per pound... all day long... everyday... for hundreds of years.
@@krisspkriss Good luck engineering a cable that could take the strain involved for hundreds of days, never mind years. And that's ignoring the times it will inevitably be struck by space debris. It's a pipe dream. Your ROI will be very squarely in the negative even if you can do it for free just based on legal fees from the massive lawsuits from those affected by the cable's uncontrolled return to earth.
Kim Stanley Robinson addressed many of these issues in his Mars trilogy (Red Mars, Green Mars, Blue Mars). They are a great read and answer a lot of the questions raised by this video. It is a simple fact that STEEL is not a viable option and a space elevator will require multiple cables, counter weighted transports, temperature stabilization, and an EXTREMELY deep anchor into bedrock, most likely a mountain in Ecuador.
I am a simple man: Common Sense Skeptic upload a video, and immediately I watch the video, I enjoy the video, and I upvote the video.
Simple!
There are some errors, it is very difficult to get these debunking videos completely correct:
- the "space elevator to geostationary orbit" needs to have its "counterweight" above the orbit. The idea is that a weight higher than geostationary orbit would "pull" on the cable to keep it straight. A weight at exactly geostationary orbit would not impact any force to the cable, and would be useless. The weight of the cable would still pull it down.
- when the space elevator is properly setup (with a weight above geostationary orbit), the whole thing would not come crashing down when the cable breaks. only the part of the cable below the breaking point would come crashing down. the remainder (the restaurant and the counterweight) would fly away in space, or more likely would get into a higher orbit around the earth.
- the orbital velocity at geostationary orbit is about 3 km/s so it is actually less than in low earth orbit. this often seems to be a bit counter-intuitive. still, the velocity of the surface of the rotating earth is only about 460 m/s so the object being raised to geostationary orbit still has to be accelerated by more than 2,5 km/s horizontally while travelling along the cable. this does not come for free, it will cause a horizontal force on the cable that is not compensated anywhere by the system, and will result in the cable "wrapping around the earth" eventually.
Don't miss this year's annual gala ISEC convention at the Denny's next to the Des Moines, Iowa airport. This year's keynote speaker: the esteemed Bob Bigelow on integrating paranormal investigation with aerospace vaporware. Channeling Tsilkovsky.
Please give the date for this event. And how does one sign up for it? If this is a past event, can you provide the information for any future events?
You sound like my engineer husband who worked at the space center for a few decades while we “rode” WDW space elevator, correcting the location of the elevator, the speed, etc going up and then again coming down. :-)
Don't forget space debris! The life expectency of a tether to LEO is literally seconds. To GEO it would be much, much shorter.
If that were the case, we'd be at full blown kessler syndrome already. Much like satellites and stations do, you could minutely move your teather by nudging either the GSO counterweight, or any station along its length to avoid collisions. The end-point is fixed (if on land), but most of the collision danger comes from mid-upper LEO or above, giving you a fair amount of play.
It's also likely if you had a power source that can send a climber up and down, you probably have the energy on hand for lots of tracking radars and laser ablation systems. What's a bigger hurdle is the material science, and geopolitical climate. No one would agree where to put the thing, who gets access or who pays for what portion of it, never mind the vast cost. This is kinda like worrying about a ferrari getting its windshield smashed by gravel falling off a truck when you have 35 cents to your name and will never be able to afford to buy one. :P
All spacecraft and significant satellites have meteorite-debris shielding. The chance to get hit is based on the frontal area of an object and its time in space. A tether, although narrow, has a hundred to thousands of kilometers of length giving it a huge frontal area and a guarantee to be hit. A tether to GEO would have to pass through "The Dead Zone", the graveyard of military upper stages. The only debris protection for that area is to get the heck through it as fast as you can.
@@BigfootxHunter That sheidling is to deal with particles too small to track, onces that likely wouldn't be a major threat to a tether. Stuff like flecks of paint, tiny screws, micro fragments and natural micro meteorites.
And it's not like we can't remediate space junk, we'll have to do it eventually anyway; because space-dumping is going to lead to kessler syndrome if we don't start cleaning it up.
If we put the money in to build an orbital elevator, putting the money in to build a 'laser broom' to de orbit all the junk left in orbit wouldn't be too hard.
Also, another factor to consider, a network of orbital elevators around the planet's equator might well make all satellites obsolete. You could just cram a package onto stations placed along the theater for the same effect, and they'd be much easier to service.
@@kauske A one gram chunk of aluminium can punch a hole through a 4 inch thick piece of aluminium plate at orbital velocities. Even the small pieces are a threat to tethers. Even the tiniest debris can cut through a steel cable one strand at a time.
@@BigfootxHunter Considering a steel cable wouldn't be able to exist at that length under its own mass, that's not a concern. That's one thing people don't understand, the materials to make a tether that wouldn't snap under its own weight from surface to LEO would have strength that would reshape engineering as we know it.
That's the rub to take home, and that's why the elevator will remain a material science issue, with all the other issues being comparatively tiny. Also, 1 g of aluminium would be big enough for modern radar to spot, it's around half a CM cubed.
The stuff we can't track and avoid is far smaller than that. And if it can be tracked, it can be avoided, or redirected.
Another factor that gets often ignored is the radiation from the sun. The space elevator needs withstand harsh UV radiation. Furthermore the upper atmosphere also interacts with this harsh radiation. The oxygen (O2) splits into two single oxygen atoms that are highly reactive. A space elevator will probably stay in service for decades and the material need to withstand these harsh conditions. A protective layer is needed (more weight) and it needs to reapplied regularly. Carbon nanotubes may be proposed as a material. But this material seems a bit sensitive to defects in the structure. This issue may not the immediate deal breaker but it needs to be considered if they actually plan to built it.
Carbon nanotubes promise incredible tensile strength, but... they are still carbon. They burn just fine. Even diamond burns.
I didn't even know they had a ride like that! That thing looks awesome!
My neighbours must love me randomly shouting "but orbital decay!" & "Tacoma Narrows!" & "Oh, Elon!".
I was walking home from the corner store listening to this video on my headphones. I literally said out loud at one point, "That's not taking into account the conservation of velocity and angular momentum!" Which might actually be the same thing now that I think about it, but my brain was getting fried listening to the apologetics of space elevators. All these dumb ideas have me so shook that I'm unable to clearly remember my terms and if I'm using them correctly or not. Oh my god...and to think people actually think something this goofy from SCIENCE FICTION can actually be done in any reasonable or practical manner.
Getting access to geostationary orbit would be useful though, there is a way to get back the angular momentum you need to rotate at geostationary by having the same mass going down. That being said, the resistance of materials will never allow that, nor the possible dramatic outcomes a giant cable wrapping around the globe could have.
I just chalk these FiSci pipe dreams as a result of The Musk Effect. The delusion that simply augmenting your imagination with impressive graphical simulations means what you are imagining is possible. Step 1: collect underpants. Step 2: ? Step 3: Mars Colony.
The CGI imagery checks out, therefore, I'm very confident that this project can be successfully completed by the end of Q4, next year. It's really not that hard!
I will accept deposits *now* for your chance to be an early investor in my new, 20 year old, startup company called *Y.* (Sure, the company appears in the Yellow Pages after that X company, however, the Y company name is a more apt descriptor of our products, services and the reasons for investors putting large sums of money into our venture. And that is more profound than it sounds.)
Please forgive me. I was channelling my inner pumpty dumpty. Now, all I've got to do is get my dad to quit his regular job, invest in an emerald mine and I'll have a better shot at becoming a billionaire.
Ive read a shipload of fiction which deals with space elevators. I keep on coming back to this question. Why not just pour that amount of energy and resources into an airline service to space? If you crash a few space airliners you dont lose the entire service. You crash a space elevator and you are back to the drawing board IF you can even recover.
Unlike warp drives, (Star Trek-) transporters and Death Stars etc, Space Elevators are just feasible enough to not scream >>>Sc-Fi
As far as we know there’s no material that has the tensile strength to withstand the forces required to build a space elevator on the Earth (or similarly sized stellar body). You can build one on the Moon though where the gravity is just a sixth of the Earth’s and there’s no atmosphere or oceans to disturb you. Problem is that the Moon itself has no stationary orbits due to gravitational fluctuations and even if it did a selenostatonary orbit would still not exist because it would be beyond the Hill radius beyond which the Earth’s gravity would have impact. You can put the counterweight at L1 though which is stationary in respect to the Moon’s surface, but is still not stable and will require you to fire a booster to adjust the counterweight every once in a while.
A proposed use for such a device is to reduce fuel costs for sending material to the Moon from Earth and from the Moon to Earth’s orbit.
The problem is, however, that since there’s nothing on the Moon, such device is currently unnecessary.
Until there is a viable industry on the Moon that mass produces and sends stuff on Earth in quantities that would make regular rockets inefficient, this would just be complete overkill despite being within the realm of possibility.
The explanation of cable harmonics brought me back to that Star Trek Voyager episode 🖖
Which episode was that?
@@kanebunce3791 Rise, S03E19
I am sure that there is some math/music nerd who can tell us all about the harmonics of a theoretical space elevator cable.
@@kanebunce3791 The Omega Directive?
But, Americans are special! They're exceptional! They can do anything - other than maintain their infrastructure, supply universal health care, have a true democracy, and weigh less than 150 Kg. I can imagine what they're eating in the restaurant as they pretend they're hurtling into space...
Lots of international tourists at Disney. 😉 Also, less than 150kg--oof! Lol
Credulous Commenter: "But they said was impossible too!"
You can't get off in LEO. You'll just fall back to Earth. Instead you'd need to get off at high enough altitude that your horizontal velocity kicks you into an eccentric orbit above the atmosphere. It would be below geosynchronous but well above LEO. I'm not sure what the minimum exit altitude would be.
Congras on a well deserved 100k...
The common theme with obital elevators in media (games, movie or animation) is always in a dystopian future. E.g Ace Combat 7, Gundam 00.
Lol is 22:20 a correct depiction, I thought it would have been like a metorite hitting the earth with the amount of mass.
That's mostly because Utopia is boring to write about..
To be totally fair to Ace Combat - I think a meteor did hit - and the whole Belka thing...
It's probably going to be impossible to get reservations at that restaurant/attraction now. Sounds like a cool experience though. Thanks for breaking this down. Any updates on "Star Raker"?
If the station was in geostationary orbit it would already be moving at the velocity nessesary to stay in orbit so anything on the station would also be moving at that velocity and would stay in orbit. This of course doesn't apply to Leo. And also doesn't explain how the weight of the tether wouldn't pull the station down. Lot of good stuff here though
One thing I find lacking in discussions on the space elevator concept is the examinaton of forces in the equatorial plane, e.g. Coriolis force acting on an elevator cabin during travel, and what that does to the whole system. Consider this:
A cabin traveling upward will experience a force tangential to the cable in the direction opposite to earth's rotation. That force _will_ tug on the cable, and eventually on the "space anchor", which _will_ result in an earthward ("anti-normal") acceleration of that "anchor". This in turn _will_ cause the "space anchor"'s orbit to become eccentric, effectively causing the anchor to oscillate in a kind of circular motion (as viewed from a ground observer) around its designated "parking spot". Such oscillations _will_ be dampened by the cable eventually, but that also means that the anchor _will_ lose energy to the cable, which _will_ convert that energy to heat.
The same process, albeit in reverse, _will_ happen when the cabin travels back towards earth. The bad news is that this will _not_ recuperate the lost energy, but rather _will_ lose even more energy.
You can't even counter this by having one cabin ride the elevator up and another down at the same time: By virtue of coriolis force they'll tug at the cables in opposite directions, but at different locations along the cable (except for that very brief moment when they meet each other halfway along the cable), so there will still be an increase in the cable tension and thus an increase in the downward force pulling on the anchor.
Now if the "space anchor" were parked _at_ geostationary orbit, that would be game over: If it were an untethered satellite, it would just enter into a lower (and probably excentric) orbit and find new equilibrium there; but that equilibrium would require faster-than-earth angular velocity, which the tether wouldn't allow. Instead, it would decelerate the satellite even further - finding new equilibrium only resting on the surface of the earth.
A more realistic "space anchor" would be parked _way_ above geostationary orbit instead, and would therefore fare slightly better. However, it still wouldn't resume its nominal position: Instead, it would settle into a lower orbit, compensating for the resulting "slack" in the cable by both shifting its partking spot further westward and also reducing the cable tension.
Eventually, even this system's orbit will drop below geostationary, and things will come crashing down - literally.
So yeah, even if you manage to get an "anchored satellite" contraption to actually work - as an elevator it could serve only a limited number of rides. Which quite defies the whole purpose of the concept.
Oh, and did I mention tidal forces?
Yeah - we'd need to get rid of the moon first.
Turns out it'll tug a "space elevator" back and forth twice a day, again causing the system to lose energy in the form of heat.
Regarding your wind turbulence suggestion, I am not entirely sure but I don't think there is any wind turbulence at the equator. If I remember correctly, there is almost no relative wind there since all wind begins there as the air is heated at the surface and flows straight up in an area known as the doldrums. When the warm air finally reaches the top of the atmosphere, it then spreads out creating wind patterns to the northern hemisphere and the southern hemisphere and the relative winds caused by the Coriolis effect. Of course this really doesn't matter in this case since the entire concept of such a structure is ridiculous.
as someone who spent 8-years in Singapore, I can tell you we regularly enjoyed some spectacular storms
It’s amazing how many people fail to realize that, if you step off the roof of a building that extends to the height of the ISS, you don’t go into orbit, you fall straight down.
I love the space concept art I saw growing up. And that is all it is, cool little pictures. 😂
Just realized you're at 101k subscribers now, congrats! (Totally missed you finally reaching 100k.)
Super happy. Now your subscriber count won't bother me quite as much while I'm watching your videos. :D
I do agree the engineering is beyond us now.
And, like fusion, will be perpetually "beyond us now".
You are absolutely right.
A space elevator can only be to geostationary orbit. They need a Massive structure on a geostationary orbit with a long tail above it. The cable is impossible to make using current technology.
Making one means clearing space from all satellite and debris to avoid collisions.
Come on then, let’s see some entrepreneurs and animators who overstepped their abilities
Not to mention Angular Momentum. The car at ground-level on the equator is travelling at 1600km/h. As it gets pulled up the cable, it will still want to travel at only 1600km/h and will tend to pull the cable backwards. This, in turn, will have the effect of reeling in the counterweight, causing its orbit to become more and more elliptical until it all comes crashing to earth. To avoid this, the car will need to be accelerated up to the orbital speed appropriate to the altitude as it climbs.
Nothing is free in physics.
I am by no means a engineer but i would assume this would be impossible due to the weight of the cables alone which is a problem potentially for Jeddah Tower which is tall but is nowhere near space even carbon fibre cables like what is planned for Jeddah Tower elevator would probably still be to heavy if it went to space
Twitter: why is this not possible?
Me: what are ya, a moron?
Ground based anchor: Super Glue- I have seen the add - really works.
People tend to believe that Sci-fi movies are all possible, do a bit of real science and most of the things they've watched are impractical or extremely improbable, like Feynman said once: “Keep an open mind - but not so open that your brain falls out.”
Great quote. I looked it up and......" the January 27, 1940 edition of the Blytheville Courier News reported that Professor Walter Kotschnig told Holyoke College students to keep their minds open: “but not so open that your brains fall out.” 1940, now that is a long time ago.
Before even watching it: how should this work when geostationary orbit is at least by an order of magnitude higher than LEO?
Angular velocity would be to low for stable orbit, it'd just fall out of the sky. The anker would need to be even higher than geostationary to compensate for the additional weight between earth and anker.
Congrats on reaching 100k subscribers. Love the channel!
Thanks so much!
@@commonsenseskeptic Yes congratulations at reaching the 100k mark of subscribers. Please keep it going because I only like the 100% truth been told. Not these lies or half truths and in some cases people living in and believing in their own bs fantasyland world as being the real deal. Again congratulations at the 100k milestone. Pete from Tasmania in Australia.
@@commonsenseskepticagain... *"NOT NEARLY AS CRAZY AS IT SEEMS"* by way of example...why land on the Moon when simply being in orbit around the Moon is an incredible achievement...and *THEN* try out the Space Elevator.
First thing that comes to mind is that the elevator seems to be in florida. Florida is not on the equator, so there's no way for a space station to be in a geosynchronous orbit above that point.
Also stuff in LEO has to move much faster than the ground below to remain in Orbit. There's a reason why geosynchrnous satellites are at a ~36 000 km orbit since the orbital speed at that distance is just slow enough to move in sync with the surface below.
I saw something on natgeo that said an SE would take 6 months one way.
I'm guessing maybe if it ran the speed of an elevator in a building? There's no reason to expect it to take more than (say) 10x as long as a rocket ship, as long as we're inventing the technology for the cable.
Just a couple points:
A space elevator would not need to be on the equator. Multiple lines could be run from differing location both north and south of the equator to counterbalance their off center torque.
Also 220 miles could be maintains if the combined mass of the object was at orbital speed. Say a ring where half of the mass was traveling at double orbital speed. But that would fall in line with the significantly better orbital ring.
150 mile per hour wind would only produce as much force as 70 mile per hour wind a sea level.
I must have missed that Musk was going to name his point-to-point offshore platforms Phobos and Deimos - appropriately the deities of fear and panic... which is what anyone boarding a Musk point-to-point rocket would be feeling.
But the feeling would be incredibly short lived...
5:01 Their is a way to have a space elevator teather in Florida. Florida to LEO station and also Peru to the same LEO station.
6:34 Eletricity from the grid (possibly to the climber or through the cable)
7:09 Rocket comparisons are not correct. The rocket is going 20,000Km/hour horizontally across the planet not verticaly. (see the altitude at 198KM at 8 minutes)
8:38 Despite all the mistakes above (2651 (km / hour)) * 8 minutes = 353km.
8:50 : Move the station out to GSO and the point on the cable at 350KM will still be stationary. This allows you to build the station.
10:23 You are above the atmosphere which means no atmospheric drag
10:38 Possibly their is a tether connecting them to the elevator above the station and they are behind the station on the orbit.
11:08 the station is traveling at 10,800km/hour if you use the same refrence frame at 27,576km/hour for the ISS. But with the plane changes the diffrence is much more then 17,000Km/hour
14:49 : The counterweight does not put any weight on the cable. Think of it like hanging a rope from a bridge. The weight of the bridge does not change how strong the rope needs to be.
15:02 Testing for the beaming part of the elevator currently use 1km cables. (Still a lot more then the required length still)
17:11 at just 8km up the air pressure is only 30% of the ground
17:51 you do not want a lot of weight pulling at the ground as that would makes the cable required to be much stronger. Even if you only have 100 tons of force then still means you can have a 10 ton climber without pulling the anchor below GSO.
19:26 If you go the ocean anchor you do not want it to be attached to the ground. You want to be able to steer your ship around the weather. The MSC Irina for instance weights 240,000 tons fully loaded. This is a pretty good anchor.
23:00: You disconect the ground station and now the cable falls stright down and does not wrap. (Plus with how light weight the cable is , it will likely burn up in the atmosphere)
23:46 Why would the higher up of cable be in the shade. The earth's shadow is only so big.
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I argue that a space elevator is more unrealistic then O'Neil cylinders and Mars Colonies.
We have a pathway to them without new breakthroughs in science (only economic). We do not have a pathway to a space elevator without new breakthoughs.
Space hotels with gravity also do not need new science(only economic) unlike orbital rings.
You say that this thing will attract lightening like no other system in the world? Great Scott, Marty, I think that we just solved the issue of how to power the space elevator … !😮
How many gigawatts did you say that we needed, Doc? 🚘
12:04 I may not remember this correctly but I think the kurzgesagt video was assuming a space elevator with a counter weight at geostationary orbit and some length of run even further out to allow the launch of stuff out of orbit.
If the counterweight station was in geostationary orbit (and there was a material strong enough to work as an elevator cable etc etc) so kurzgesagt was saying something accurate, by definition if you are in geostationary orbit you are in orbit.
The counterweight cannot be at GEO .. has to be well beyond to keep the tether taut (via centrifugal force) or both the tether and the counterweight will fall to Earth
@@xenuno usually the models have a very heavy rock at the geostationary position so that it doesn’t get pulled around easily and a much smaller counterweight on a second tether at a higher position that can be winched up and down to keep the masses balanced and keep tension on the cable etc, it could also serve as a launching point to send stuff out of earth orbit.
@@glenecollins Ya I spose that would work but all the models prophesize tether properties and dynamics based on Unobtainium, specifying strength, density, and a host of other properties that real world materials do not and will not ever possess
This just in - SpaceX attempt a second launch of the Starship, although booster separation was successful, it _exploded_ in perhaps one of the biggest blasts I've ever seen. It gets better, mission control Boca Chica lost contact with the Starship, it exploded at suborbital altitude, and once again, just like in April, SpaceX attempt to save face by calling it "A Rapid Unscheduled Disassembly", in other words, it means it blew up again.
This also in - the test worked a sight better than the April test, and didn't do any damage to the ground. SpaceX can get another test on the platform by the end of December if the naysayers will let him.
Fusilier7 doesn't seem to be one as will let him.
A one inch thick braided steel wire cable weighs roughly 2 pounds per foot. That means a cable reaching to geostationary orbit would weigh 118,080 tons. However, that same 1" thick cable will fail at 65 tons of tension. You'd need a material that's 1,800 times stronger than steel just to support it's own weight.
Materials science is not yet up to the task...
10:50
Small correction, they wouldn't burn up in the atmosphere specifically because they aren't moving fast. Instead they would just fall until they reached terminal velocity and then smacked into the Earth.
I don't think you are right. They start move-less at 350km above ground ~~ 270km above 'the top of the atmosphere'.
Applying just basic physics. (s=1/2*g*t*t and v=g*t), it would take them ~233s of undecelerated free fall before reaching the top of the atmosphere, reaching speed of ~2330m/s = 8400kmph or 5200mph or Mach7.
I'm no expert, but entering atmosphere verically down @Mach7 WOULD pretty much cause you to burn down into a charcoal. Pretty much like Vladimir Komarov did.
There is another big problem. The rising capsule has mass which must also be accelerated at right angles to the cable, as the farther it gets from the surface, the larger a circle it''s motion will inscribe and the more rapidly it will be moving around the Earth. It will be moving faster at the terminus than it will at the Earth's surface. So, it will resist that lateral acceleration and induce a lateral force on the cable, drawing it back opposite the direction of rotation of the Earth, like a bowstring. Some sort of thrust will have to be applied to offset this, or it will massively load the cable and likely pull the counterweight down toward the Earth and/or stretch the cable. The opposite problem will be encountered on the return trip, with the capsule having to bleed off rotational velocity, again with a thruster of some sort. The amount of thrust will increase as the operational speed of the lift increases. This counter thrust will undoubtedly add to the vibrational harmonics. A smaller thruster can be used over a much longer time if the elevator is slowed down considerably, by taking a few hours or longer to make the trip.
@@shanent5793 The total amount of thrust applied is the same no matter how slowly or quickly you go. So, you have to use the same amount of reaction mass, which is enough for a round trip. The mass for the return trip adds to the amount you have to bring for the ascent, as it also needs to be accelerated to orbital speed. A slow ascent means that there will be more water, food, and waste processing capacity in the capsule. Perhaps sleeping facilities, too. if you end up spending a couple of days in the capsule, you will need a heavier capsule, to provide additional radiation shielding. Instead of a bus, it begins to look more like a train with the attendant mass increase, complexity, and energy requirements.
@@shanent5793 You are only considering the primary frequency of the cable, you have no idea of the number of harmonics which are possible and which ones would be destructive or at what amplitude you may get degradation of the materials in the cable. If it's a single crystal, that is one thing, if it's a laminate of monoatomic thick carbon matrix that would be a whole different deal. How much would it take for a meteorite or bit of space junk to nick the cable, causing a sufficient single point failure. Like opening a potato chip bag.... can't tear it until a little nick is induced and a stress raiser is caused.
@@shanent5793 The capsule needs to be accelerated laterally, as well as vertically. It needs to be going around the Earth faster when it reaches the terminus than when it left Earth, as it is inscribing a larger circle during the same amount of time. The cable can induce that by providing resistance, with the capsule deflecting the cable like a bowstring being pulled. This induces a harmonic as the cable rises with the point of resistance moving up the cable at whatever rate of rise is found to be sustainable. If the cable can't stretch, then the terminus will be pulled downward, with the maximum deflection coming near the middle of the trip.
@@shanent5793 Until you reach resonance. Then..... And that isn't my primary objection to the situation, as just varying the velocity of the capsule at random could probably dampen the harmonic resonance or the primary wave.
Congratulations on reaching 100k subscribers, and thank you for the content you create.
This wasn't mentioned either........... A long cable sweeping through lower orbit will acquire an enormous amount of electrical charge. An LEO satellite experiment to see if power could be generated ended up melting the cables. During a solar storm, the amount of electrical charge could be truly terrifying.
This video takes me back to the 80's when I first read about the idea and excitedly asked my physics teacher about it. She told me it was a daft idea, pointing out many of the problems highlighted in this video. I was a little upset that my easy trip to space wasn't to be, but at least I learned about orbital velocity!
20:08 this is actually a self propelled ship that is dynamically positioned usong theusters...and a consteuction ship that not connected to the sea floor unless they are lifting or setting something onto it with the cranes
I just witnessed another SpaceX launch failure and am so looking forward to your next video about the event. All the fanboys along with SpaceX have already begun to spin the event.
Did it fail? I think I watched Thunderf00t's video and it went OK, at least in the launch part and all engines working part.
Did it fail later?
@@Albtraum_TDDC I thought the purpose of the launch was to head to space, circle the earth and land somewhere in the Pacific near Hawaii? Why did it explode? Is "ok" what they were aiming for? Did I get it wrong? If there is a "space" mission with "goals" and the goals aren't realized, do we then call the mission a "success"? Did I miss the realization of SpaceX's attempted achievements? Or, are we living in the upsidedown world where we call failures success? If this test flight had a crew onboard, would it have been considered a success? Please enlighten me.
@@QuestionEverything-qp6kw I was just asking. So it exploded after launch, but made it to orbit? Why did it explode? I thought only the stage one rocket exploded, when it was supposed to be reused after landing. Did the whole rocket explode later?
To be fair, while you can't have the bulk of your elevator sitting in LEO; physics-wise, you could have a small stop-off hanging from a bigger counterweight that is at GSO or higher. Effectively, you could put any number of stops along the cable (or cables) and they'd hang in-line with the structure as a whole. You can also put things above GSO and use them to hurl objects onto escape velocity; assuming we could find a material durable enough to work out for Earth's gravitational pull.
There's probably zero chance the first elevator would ever be put out by a lone private entity though, it would be a massive, likely international undertaking if we ever unlock some sort of super material that can do the job. Also another thing to note, a singular teather is likely not a sustainable system overall anyhow; as you move mass up and down the structure, you'd have to constantly move counterweights around, esp if you are moving cargo around outside the GSO region of the structure.
I imagine you'd need dozens, maybe hundreds of theaters for a system with multiple climbers and stations along its length, all with adjustable counterweights to stop the structure from going slack due to climbers moving along it, and cargo or docked craft being added, removed and repositioned.
I thought this was already debunked《is not even an unreasonable idea,it's just stupid》
No, it’s totally bunk. 🤣
@@albeit1its possible to do this on the moon with normal materials, not even some super exotic stuff, just a steel cable.
If you're going to qualify it with "not counting the tower of Babel", you could also add, not counting "Jack's Beanstalk".
Babel pre-dates Jack.
@@commonsenseskeptic OK, that's a good point. Then how about the Norse mythology story of "Yggdrasil" the cosmic tree which connects various different realms. The trunk rises through the middle realm of Asgard, thereby connecting all the nine worlds of Norse cosmology.
Now yes, Babel predates that too, but it's still an interesting historically analogous story of a space elevator.
I saw something once where they spoke about space elevators and the problems with the materials we currently have that could be used for such a device.
They looked at spider web as a viable material if we could make it. It would be light enough and strong enough to hold itself together, tethered to a heavy thing in geo-sync above.
Dont remember what else they spoke about.
spider silk is not even close to being strong enough.
I'm not sure if it was done yet, but there are plans to genetically modify silkworms with spider DNA to increase production to be viable enough for textiles.
As far as I have seen the only viable material has been carbon nano tubes which is still under development
Quick question ... how many bridges are built out of spider webs? Or nano tubes for that matter?
@@UA-camBorkedMyOldHandle_why There are a few reasons space elevators are sci-fi, one of which is we don't yet have material(s) light, strong & flexible enough without stretching too much.
On the accelleration, to quote Doctor Brief from DBZ abridged: "You'll be crapping out your own spine."
If there are educators attending this space elevator conference, their employers should reevaluate their employment.
Nothing says "skeptic" quite as much as believing that everything that exists today is all that will ever exist...
Not at all. Educators should always seek new information.
@@eldenfindley186 they need to think and filter any flecks of gold from the mountain of poo
@@insu_na you must think magic is real.
@@hanspecansmaybe exactly the way someone in 1800 would have thought pulling some little flat object out of your pocket and talking over moving pictures with someone on the other side of the globe was magic? Yeah, with enough determination and incremental scientific and engineering progress “magic” becomes an accepted element of daily life.
15:35 😳😱 GOT DaMn son, this part scared the crap out of me! I had the screen off and my headphones on listening to this episode while I was cleaning 😂 🤣
Maybe use the tether itself to generate power from the electrical potential energy difference between earth level and upper atmosphere.
Satellite deployers could consist of a rotational launcher a la Spinlaunch, or maybe a railgun type linear launcher. It would still require acceleration to orbital velocity, but that should be much easier to achieve without all the atmosphere in the way.
The weather and resonance from winds blowing over the tether seem like maybe the tougher nut to crack. And how much is the length going to fluctuate from thermal expansion?
Overall would likely make much more sense to look how to build autononmic, self reparing drones which mine the moon and build something out of that if possible.
We overall should focus more on that before starting to look into space, beause without such technology, there isn't much we can reach up there.
As soon as we got drone which can build a whole city on their own on earth, we can think about if they can do that in space.
Else: what's the point even to create such a space elevator or whatever in the first place?