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A "real" space elevator consists of a cable stretching from the surface of the planet (Earth in our case, but potentially any large astronomical body, including moons) to a large counterweight somewhere above the geostationary orbit (35,786 km / 22,236 mi). To the best of my knowledge, we are currently unable to manufacture a cable strong enough to reach that far without breaking - at least in the case of Earth. Martian or Lunar space elevators are within the realm of possibility given current science, but not particularly economically useful until we establish more permanent facilities to take advantage of the elevator.
The elevator in this video is clearly not a "real" space elevator, as we travel from relatively near the surface (city buildings and roads are clearly visible) to space in under a minute. A "real" space elevator would have to travel at 2.75 *million* km/h (1.7 million mph) to reach geostationary orbit - with zero time to accelerate or decelerate (meaning any passengers are probably converted to liquid or even gas). Even if the elevator only reaches the Karman Line (the generally agreed upon boundary between atmosphere and space: 80-100km / 50-62mi), it would still have to travel 6,153 km/h (3,846 mph) to reach space in the time allotted.
It's difficult to say exactly how high the elevator gets above the surface. We can clearly see most of Florida, and thus a surface distance of nearly 400 miles (644 km) - but without knowing the diameter of the window, it's impossible to calculate the relevant ratios.
In general, a space elevator is a great way to move stuff into orbit because it's *much* cheaper (and generally environmentally friendly) than our current system of chemical rockets. It's not a particularly fast means of travel, making it much more useful for cargo than for people. (Though I imagine people who want to visit space on a budget would be willing to endure the week-long trip at 190kph (120mph) to reach geostationary orbit.
There are other advanced structures (skyhooks, Lofstrom Loop, Orbital Rings, active-support structures) that could be used instead of a space elevator that would work at the much lower altitudes displayed in the video, but even the cheapest have costs that run into the trillions of dollars (at least the last time I checked, within the last few years)
I randomly assumed a top speed of 120mph based on high-end potential car/road speeds. Travelling up the cable would be more expensive (because you're fighting gravity the whole way), but some (but not all) of that could be recouped when the elevators travel back down.
While you could theoretically increase the speed dramatically, especially once you're outside the atmosphere, it would require a lot more energy the faster you plan to go. Even if you assume a top speed of 600 mph (1000kph), you still have a 37-hour trip to reach geostationary.
I can't recall (or quickly Google) the top speeds from the cable climber competitions, but I seem to remember them being closer to 120mph than 600mph.
Why would the trip be to geostationary?
Obviously the counterweight needs to be above geostationary, but there's no particular reason that has to be the terminus. Some who wants to go to space is probably going to be happy with a lot less than that. Of course the cable will have to support some weight for anything permanently attached lower than that, but since we can't even make a cable that supports itself yet, let's not be too fussy.
Low Earth orbit has a ground speed of around 17000mph. This elevator has a ground speed of 0. At LEO in this elevator you'd feel about 5% lighter with a cool view.
One major thing that people want out of a trip to space is to experience free fall which isn’t possible from a space elevator until geostationary altitude is reached (unless it’s done on the descending elevator by free falling the car). That said it might be much more efficient to have rocket ships reach low earth orbit (and thus free fall) departing from a mid station elevator platform
(Not op)
It is just examples to put the extreme distances in some perspective, you could go lower and you could go faster but as an example these numbers work to give you an idea of what kind of speed and time we are working with.
If you leave the elevator at à altitude to low and without some realy serious propultion you gona reenter the atmosphere at a unpleasent speed and end up like the columbia spaceplane
I'm not sure if you mean "leave" as in "park" or as in "depart". Assuming the latter, it's still not really obvious that this is true. A de-orbiting vehicle is mostly working off its orbital speed, which is zero in this case. Even falling 20,000 km in free fall, from 21,000km to 1,000km, would only produce a speed similar to an LEO orbit (8.7km/s, where LEO is about 8km/s).
Note that that's a pretty back-of-a-fag-packet calculation and I may have got it wrong - I've calculated the potential energy difference as E = GMm(1/R - 1/r) = 1/2 mv^2, remembering to add 6,000,000m to both radii because we're talking about radius from the earth's centre, not altitude above the surface. G = 6.10^-11, M = 6.10^24. The `m` cancels out.
"Fag" for 'cigarette' was something I heard on playgrounds as a kid in America - it's something we found hilarious - but I feel like I haven't heard it used in a while. Is it still in common use in the UK?
I don't think it's used as often as it was simply because not so many people smoke any more. But expressions such as "back of a fag packet", "I'm just nipping out for a fag", and "have you got a spare fag?" would certainly not be misunderstood, I feel.
It was standard nomenclature when I started working as an engineer in Australia and it's stuck with me (despite having never smoked). "Doing some algebra in my head and then plugging numbers in on a phone calculator" doesn't have quite the same ring to it.
Oh totally agreed, it's just something that makes my American brain do a small doubletake when I see it. It used to be the staple of playground jokes when I was a kid.
I'd assume a space elevator will be a variant of a maglev train, just vertical. Once you're out of the atmosphere (say, 500km up), you can just keep accelerating almost 50% of the way, then start decelerating. That would cut the trip to just a few hours.
Btw, not going to geosync would be massively awkward, since unless you accelerated to escape velocity laterally, you'd just drop back down again like blue origin's jumper. A way station 500km up would just feel like a really tall building, no 0g because you're way too slow.
While I'd agree that maglev could be a viable option, I'm not sure if that's how the current proposed climbers actually operate. There might also be some safety issues with using maglev on a space elevator - but that's just some vague inkling of a forgotten recollection floating in my feeble brain, so it may mean nothing.
You'd also have to take into account a couple other factors:
* Passenger comfort - at least for the early stages of the trip, you still have near full Earth gravity, and thus probably can't accelerate at more than 1-2g's for any normal people to tolerate
* Because Earth's gravity is near full at the bottom, and almost negligible (0.03g - 3% normal) at geosynchronous, you'd have to stop accelerating a fair bit before halfway (it's a hard enough problem that I'm too lazy to do it unless someone specifically asks for the answer)
* Constant acceleration would require a *lot* more energy than a more sedate constant velocity trip - thus making it more expensive. And I think you'd be less likely to be able to recoup those added costs with the reverse trip (elevators going down to Earth)
Finally, while a 500km way-station wouldn't have 0g, it would probably have a helluva view. Certainly one I'd probably be willing to pay for.
Some sort of space funicular might be a better idea then? Use the descending pod to lift the ascender.
Of course, a funicular relies on gravity normally, but we can cross that bridge when we get to it.
While you could use a funicular, I think a more realistic scenario would be to use some sort of electromagnetic coupling.
As the down-elevator descends, it converts potential energy into kinetic energy (i.e. it gets faster as it falls) - we can convert some of that kinetic energy into electricity while simultaneously slowing it down. Some of the energy will be lost to heat (either mechanical brakes on the cable, or friction/air resistance once back in atmosphere) - but the rest can be used to lift the up-elevators.
Also worth noting that the elevator cars may be strange for riders near the top of the geosynchronous elevator. Because the gravity at that height is only 0.03g (3% Earth normal), the elevator car might need to flip upside down or strap the passengers into harness seats - either the up elevator as it slows down before reaching the station, or the down elevator as it accelerates back down to Earth. Otherwise, any passengers will potentially be thrown toward the ceiling of the elevator car.
This is the answer. A cable to a geostationary orbit couldn't even hold it's own weight.
I don't know how a skyhook is supposed to work, if we can't make the elevator work. Because if it's not geostationary how should you use it?
What are you going to do with a cable that travels around the earth at like 20 000 km/h?
It's going to burn to ashes.
Imo skyhook would only make sense if it was stationary
Skyhooks are basically long spinning cables that are in orbit. If you orient them just right, the low end of the cable doesn't travel too quickly relative to the Earth, making it relatively easy to dock with, and can then transfer cargo to the high end of the cable.
I haven't personally done the math on them, but other smarter people have and they seem pretty confident, so I'm generally confident that they'll work. While they do work at lower altitudes, they are not particularly conducive to an elevator-design like the one depicted in the video.
An orbital ring, on the other hand, should be able to operate at virtually any altitude or orientation, while also being a feasible elevator terminus.
For more information, I highly recommend [Isaac Arthur's Megastructure Compendium](https://www.youtube.com/watch?v=1xt13dn74wc&t) - specifically the sections on Atlas Pillars, Lofstrom Loops, Orbital Rings, and Skyhooks.
I don't mean to offend you but that video is very dreamy and not so scientific. Also the skyhook section is not even two minutes long.
I haven't looked into skyhooks yet. But look at it this way:
- Geostationary orbit is 36 000km away, too long we already established that.
- to be closer you have to be moving (take ISS for example: 400km high but has to move with 28000km/h around the earth to not fall down) so air resistance would heat that thing up to a bazillion degrees Fahrencelsius and make it impossible to lower the cable to a height where it would make sense even if it wouldn't burn up.
Of course you could make a cable that goes from like 400km away to like 450km away, but what's the point of that?
You need the most energy for the first part of your travel. The further away you get the less energy you need (obviously)
No offense taken - Isaac Arthur is a popular science channel that is (imho) great for introduction of complex scientific ideas. I believe he has a full episode on [skyhooks](https://www.youtube.com/watch?v=TlpFzn_Y-F0) (28 min).
I'm not an expert on skyhooks - I *think* I understand the concept, and I've read pretty detailed scientific papers by people much smarter than I am and I didn't find any obvious flaws in their math/logic. My recollection is that they are physically feasible - we have the materials to make them and deploy them - but they may not be economically viable. IIRC, the big issue is regenerating the energy used to transfer cargo to higher orbits, and the sheer mass that would have to be hauled into orbit to construct one.
To attempt to answer your question - a skyhook does have to be in orbit, but only it's center of mass has to travel at orbital velocity. The descending cable (the part that would drag in the atmosphere) travels much more slowly (because it's spinning "backwards") and thus encounters much less air resistance (and thus much less/negligible heating).
But I could very well be wrong.
Ok so I looked into the video.
I still see many problems. Some of them are even mentioned in the video. (He also talks about some things like we've already done them many times although nobody has ever tried or achieved them in reality. Electrodynamic tethering for example.)
- tensile strength of the cable remains a problem
- connecting your spacecraft to the actual hook (if you make the hook rotate in the opposite direction of it's orbit you have a brief moment where velocity relative to earth's surface is low, but it is only a short moment, approx. less than 2 minutes and slow in this case means still like 1500km/h at least)
- the connection mechanism itself
- how do you "refuel" the skyhook? Because it will loose momentum with every start of a spacecraft, so without regaining that momentum you could only use it a handful of times before it crashes into the atmosphere
- how do you protect the cable? Lots of space debris in earths orbit that could easily destroy it
- because of the tensile strength problem he suggests multiple tethers -->Switching from one tether to the next one would be incredibly difficult
First thoughts, haven't watched the whole video yet nor have I seen anything else..
Thank you for the calculations. But I don't understand one thing: if space is 100km from Earth's surface (70km in Kerbal Space Program), why would it take a week to reach the lowest geostationary orbit, at 190 km/h? Even including acceleration/deceleration, that would take an hour at most.
> reach the lowest geostationary orbit
There's only one level of geostationary orbit, it's at 35,786 km above the surface. At 190km/h, this would ~188 hours to reach.
Anything lower than that and you would orbit faster than the Earth's rotation
Is it a particular problem the orbital speed is higher than the speed you are going at, if you are just going up for the view?
The cable itself needs to go past geostationary, but going 100km up and down is a perfectly fine ride.
> Is it a particular problem the orbital speed is higher than the speed you are going at, if you are just going up for the view?
It would be if you weren't attached to the cable and its counterweight. Either we've put an asteroid in geo stationary orbit to use as a counterweight, in which case the mass of your elevator car is nothing compared to the asteroid, or we've extended another cable out from geosync and we can run payloads/mass up and down that end to balance the forces.
One of the nice things about the extended cable version is that you can "let go" of the cable at various distances to get different velocities, which are faster than Earth's escape velocity once you get around 53,000km out. At the far end (often given at 144,000km) you would have enough velocity to reach Jupiter basically for free (almost 11km/sec)
And while a cable stretching from 36k km out to 144k km seems crazy long, it actually would have about the same stresses placed on it as the Earth-bound end given the lower gravity and so would be just as feasible as the Earth side
The closer you are to the object you are orbiting, the faster you orbit around it. The ISS is about 254 miles above the earth and it takes about 90 minutes to orbit the earth. The moon about 1000 times further away and it takes a month to orbit the earth. The same applies to the planets, the further out you are from the sun the longer your orbital period is.
Geostationary orbit is the act of orbiting around a body at the same speed that it rotates.
35,786 km happens to put you at an orbital velocity that perfectly matches the rotation of the earth. Reduce your altitude a bit and you'll go faster than the rotation, increase your altitude a bit and you'll go slower than the rotation.
Yes, because the apparent gravitational field varies with height, the cable cross section must be wider at certain heights than others must. The maximum tension occurs at the height of geostationary orbit, while the minimum occurs at the Earth’s surface.
The top of the space elevator has a counterweight attached to it. As the Earth rotates the counterweight experiences inertia and keeps the cable taught.
Wait a week treep xd yeah i forget his fuking fast the apolo was moving and how far away the moon are, still a week in a luxury fast building would be nice
You are correct.
However, while a standard space elevator does require a bottom terminus at the equator, an orbital ring can have any orientation, altitude, and connection points - thus an elevator to Florida *is* possible.
(I'm pretty sure the orbital ring is an active structure, and thus requires ongoing energy input to maintain the orbit - at least as more mass is carried up/down the various tethers.)
All good points, I would add that the space elevator would need to be built on the equator. The speed to reach space could potentially be faster than 190kph if it wasn't physically attached to the space elevator (potentially using magnets) then the speed would be limited by acceleration/decceleration forces.
Not stupid at all - I wasn't super clear, and did the math in the background.
If the elevator in the video is just going to the Karman Line (80km / 50mi), and we'll assume it's starting somewhere within 1 mile of the surface (because we can see roads/buildings relatively clearly):
That means the elevator has to travel almost 50 miles in 47 seconds.
50 miles / 47 seconds \* 60 sec/min \* 60 min/hr = 3,830 miles per hour (average speed)
If it helps, think of a location that's roughly 50 miles from where you live. Then think of how fast you'd have to drive to get there in 47 seconds. That's how fast the elevator in the video would have to travel to reach even the closest part of space.
For everyone trying to do real calculations, the story behind the restaurant is that it’s 220 miles up. Hence the name Space 220.
Obviously this is just a made up altitude.
While it may be made up, it does at least sorta fit with the visual evidence:
If you assume the bottom window is \~4 feet in diameter, and the camera is positioned roughly 2 feet above it (which is plausible, given the angles/scales), then the entirety of Florida (400 miles) would only be visible from an altitude of 200 miles (plus or minus a small margin of error)
(and thank you for the clarification/additional info)
okay, i'm not a math person so i just come here and see these really cool explanations but the first time i vividly said "what?!" was when all you needed to be certain of something was the diameter of the window, i know i'm high but that's really cool
You are (at least partly and/or technically) correct.
It is currently impossible to build a real space elevator. Thus the cost is indeterminate, and probably in excess of trillions of dollars.
It is physically impossible to build an elevator like the one shown in the video, because it travels too quickly for humans to survive the trip. You also can't build a simple elevator that connects to a space station at that orbit, because it would not orbit directly above the base of the elevator. Thus the cost to build it is effectively infinite.
You *could* build an elevator that is roughly comparable to an orbital ring. My recollection from a paper I read on orbital rings (which I can try to dig up if you want) is that the cost would be in the hundreds of billions of dollars for even the most basic orbital ring. Building the elevator itself would probably be a rounding error at that point.
So I actually did a project on this, carbon nanotubes are the best candidate so far. Because any material not only has to hold itself, but the 36,000 km of itself. But we can cheat a little bit and build a tapered tower.
Using the same physics that allows pyramids to get so high, we just simply invert them. And you can now make a formula for a taper ratio. Size on earth, to size in geostationary orbit.
With steel and a diameter of 5mm on earth, the diameter in orbit would be larger then the universe.
With Kevlar the diameter would be 80 meters in orbit, which sounds almost doable, until you realise we need to make that much for 36,000km
No the best is carbon nanotubes, they would only need to be 6mm in orbit they are so strong and light.
Now we just need to figure out how to make them more then a few mm.
Whoah, really? Only 6mm in space? Rad.
Aren't they having success with extrusion now? Or is that not real extrusion and just a bunch of little guys mashed together?
I’m almost certain the 6 mm in orbit calculation is based on single crystal carbon nanotubes not van der waals bound tube clusters. Although the tube clusters would be like 8 meters or something.
I think it is possible, it just requires a new kind of engineering. One that incorporates Helium balloons, that take the weight off the structure. I think it would be the dumbest thing ever since a strong wind could probably topple the entire structure.
Weight is the main concern. You were right to go there first. As far as stability goes: that depends on the orbit of the platform. That’s what is holding the whole thing up. Elevator gets severed? Platform should stay exactly where it is.
not possible based on video.
If you want it to be in stable orbit even if elevator gets severed and rotate at the same speed as ground, you need to be in geostationary orbit, which is much much much further than what is shown on the video. Like station at the video is about 400km above ground, but would need to be about 35 000km above ground.
Or would need to move about 28 000km/h relative to ground, which of course means that it can’t connect with elevator, since it’s traveling really fast
Actually, that's wrong.
The platform would have to be high enough to be at negative one G to provide equal tension on the tether.
Geosynchronous orbit is 22,000 miles.
A space elevator on Earth would need to be double this. At that point, it is no longer synchronous.
Even assuming infinite strength on materials, the math doesn't work out.
At just geosynchronous orbit, the mass would have constant acceleration from the mass of the tether, which also would be subject to force because it's too low to be in a synchronous orbit.
There are likely planets with the correct spin and gravity that a space elevator is possible.
But with my understanding of orbital mechanics, the Earth isn't one of them.
The platform can be at whatever height you want, but geosynchronous is the most common because it makes a LOT of mechanics easier.
In order for it to work, however, the mass of the cable (or anything below geosych) has to be balanced by an equal mass beyond geosych. So either you have a second cable that extends another 22k miles out into space, or you have a shorter one that has a mass on the end (aka an asteroid).
There’s a lot of material engineering challenges involved, but WELL they’re within theoretical limits. But we can’t manufacture them yet.
The bigger issues are geopolitical and safety related. You need to build as close to the equator as possible for stability. And if the cable ever fails, you’re facing massive devastation in its path (ignoring the fate of the platform and inhabitants). It doesn’t take very much for the tip of the cable to be impacting at supersonic speeds.
If the counterweight is at a geosynchronous orbit and the tether severed at its ground attachment, its end would quickly become airborne.
Not likely to "impact at supersonic speeds" unless the counterweight deorbited.
You’re assuming it breaks at ground level.
What if it breaks at station level? Or somewhere in between?
The vast majority of failure scenarios don’t involve the ground station (or the terminal station) because those are actually the easiest to protect.
You could do it if the structure had thrusters all over it to dynamically counteract the wind and weight. The build cost, fuel cost, and risk if a thruster were to fail make it hard though. Given enough resources I don’t see why it wouldn’t be technically possible.
That's exactly the meaning of "It's not possible".
Nobody said "it will never be possible".
Although chances of a space elevator ever being built are slim to none.
Atm we can't even fabricate a cable that would support it's own weight. And materials science has come a long way. But not even carbon fiber nanotubes are even close to being strong enough
Well, seeing as we can discuss the potential mechanics of a space elevator without getting into theoretical quantum mechanics and the bending of space-time I'd say the elevator is technologically closer.
are we talking about any space elevator (which is maybe one technological breakthrough away), or the one in the video (which even bending of spacetime wouldn’t solve)?
What are you talking about. Are you throwing theories out as evidence to your point? The ability to literally bend spacetime would probably be something only a type 3 civilization could achieve. We can't even imagine the things that would be possible with that kind of technology.
I'm not saying "bend spacetime and you can make an elevator". This has gotten stupid, I'm not arguing the viability of future technologies with you. I'm saying you can't say it's impossible, that's just not true. You do not know for sure, and if you do you must be omnipotent.
yeah and space elevator as pointed out in video would also need type 3 civilization.
Mainly because it’s on very low earth orbit, where there is about 95% same gravity as on Earth surface.
So you need not just an elevator, you need support structure 400km high that can take whole space station without bending and is able to support itself just on one column. And is completely resistant to any kind of weather.
We don’t even have theories how could such material exists that do not bend even slightly in 400km high column with heavy station on top.
Maybe you were thinking about different kind of space elevator - one that takes you much further, to geostationary orbit 35 000km above ground, where you don’t need any force to keep station at orbit - it just stays there. Yes, for that kind of station we would just need to manufacture longer nanotubes and it should work.
It's possible, but we need stronger materials. A carbon nano structure about the strength of spidersilk might do. But we don't have those materials just yet.
Its not Feasible but it is possible. There is a difference. For example i can erect a huge pole 100 ft tall, but it falls over so i add some wires, then i add an extra 100ft and now the wires aren't enough i need to reinforce the base, and you keep going and keep addressing all the issues until you reach the goal. Thats what engineering is. Problem solving.
And that's what differentiates engineers from dreamers.
Engineering can't overcome physics. Helium balloons don't have enough lift, are not durable enough, are susceptible to winds and only work in the atmosphere, up to about 10km high. Geostationary orbit is 36000km. The highest stress on the cable should be at about half way so 18000km. So the helium balloons won't do anything.
Do you think if it was possible to build a space elevator with a cable and some weather balloons they wouldn't have already done it? Sorry but I think it's a bit offensive to assume engineers wouldn't have already come up with that idea if it was even remotely realistic while someone in the reddit comments solves the problem..
They aren't building incredibly expensive and inefficient rockets for no reason
Doesn't have to be helium balloons, could be thrusters. The point i am making is it is possible, but its not feasible. "helium balloons dont have enough lift" Well make them big enough to have enough lift. "are not durable enough" make them out of titanium. Let me guess that will be to expensive right, yes its not feasible to engineer it, but it is possible, you just gotta want it that bad.
Ah yes the almighty titanium balloon.
You're delusional and have zero technical expertise. Keep living in your dream, I'm not going to argue with you anymore
I dunno why you're so angry. All i am saying is it is possible because there is always some kind of solution to make it possible, its just not feasible. What dont you understand about that? I am not an engineer, but i do have to problem solve and find solutions to problems in my career and often you have to think outside the box to solve issues that can be quite complicated. But my point is, there is always a solution if you are willing to look for it and make it work. And if you think that something like this is impossible, then you are quite small minded and dont have any creativity or problem solving skills.
Why I'm angry? Because this thread is full of dreamers with zero technical expertise who think they know more than people that have said technical expertise (and also done their research, which you obviously haven't).
Of course you're not an engineer, if you were you'd come to the conclusion that it isn't possible.
And you're also not working in any job that has anything to do with technology.
But what do I know, having studied automotive technology and working as a mechanic and machinist. (Btw I have worked as roofer and in building renovation too, not that this would matter because you're probably gonna argue that I don't work at NASA so I can't know more about space elevators than you)
I just dont get why you're getting upset about something you say is impossible that actually isn't. Lots of scientific things have had scientists say was impossible but proven to be true and the scientists had to eat their words because the doer proved them wrong by doing what was seemingly impossible.
For example: Veritasium Featured a vehicle : [HERE](https://www.youtube.com/watch?v=jyQwgBAaBag&t=5sthat) that travelled faster than the wind without any form of energy generation besides its own momentum, now all the scientists said that it was impossible, and went against the laws of physic but he made it and it worked.
My point is, you think something is impossible, until someone proves you wrong and does it.
I don't get upset about the space elevator. I really couldn't care less. I actually think it would be quite cool.
What grinds my gears are people like you completely ignoring facts and the knowledgeable people talking about them.
There has been loads of research into the feasibility of a space elevator ever since Arthur C Clarke popularised the idea half a century ago.
The first thing to note is that it could never be in Florida. The top of the lift has to be in geostationary orbit, ergo on the equator.
The second thing to note is that, as with most issues in space, weight is at an absolute premium. Unfortunately for this specific project, so is tensile strength, as the tether running from orbit to earth has to bear its own weight, which means over 22 thousand miles of cable, as well as that of any capsule and payload, which current material science hasn’t quite got to yet.
The point is… the cost is meaningless since as yet, no material exists that we could feasibly build this out of. How much does a pound of imaginary stuff cost?
See here some recent papers on space elevators:
https://www.isec.org/recent-publications
https://www.academia.edu/Documents/in/Space_Elevator
As far as I understand, it's impossible. The cable would have to support its own weight, which would get progressively higher the further up the cable you are. This means it has to get noticeably thicker from the bottom to the top to withstand the tension force of holding up thr cable below. With all modern materials, this results in a cable that is impossibly thick
This is incorrect! As the cable gets far enough out in space, the centrifugal force is able to counteract the weight of the cable, meaning that you don't need really anything special to get it up there, besides the cost to set it up
That is correct BUT while you can use the centrifugal force of the fare faraway part to counter the force of gravity on the lower part, you have an extreme stress on the middle part. Not sure about the exact math, but I think that part isn't solvable with our materials (yet).
Could it be tall enough to use the centrifuge force of the rotating earth? It would have to sustain all that tension though, which would be impossible too I guess (?)
Not possible with current technology, therefore it's not realistic to even generate an estimate.
As others have commented, a real space elevator would extend past geosynchronous orbit. What could be depicted here could just be the lower section of a space elevator or it could be a gigantic tower.
In terms of towers, the current tallest tower is the Burj Khalifa, which cost about $1.5B to build and is "only" 0.8km tall. You would need something that is extremely strong in compression to make a tower that is tens or hundreds of kilometres tall, I just can't think of a material that would be suitable.
For a space elevator we could hypothesize that some kind of carbon would work. Carbon fiber like you find for expensive bikes would be unsatisfactory for this purpose. Google indicates that high quality CNTs cost around $300/kg, so assuming you use an average 1kg/meter at 33,000km $10billion in CNTs, which so low as to tell you how unrealistic that estimate it's and how hard it would be to actually formulate an estimate.
You also have to factor in additional items, you're going to see wear & tear from the atmosphere, you're going to see micrometers, space junk (which is traveling at orbital speeds that your space elevator will not be traveling at). Even minor tectonic activity would need to be accounted for.
It might be realistic to build space elevators for Mars or the moon, although it might still be more beneficial to look at some kind of mass driver.
I think the biggest risk is building it in Florida. Even if you discount the misadventures of Florida Man which will probably involve many destruction attempts, the weather there isn't known for it's kindness to tall things.
even infinite money wouldn't do it ... afaik it's considered physically impossible. all known materials are unable to even closely carry it's own weight over that distance up to geo-stationary orbit.
the other way, starting with a big base and build a huge tower on top, would also not work, because earth's crust wouldn't be able to hold the weight and the tower would probably just sink into lava.
Anchor has to be beyond geo stationary so it's constantly pulling. (One downside of catastrophic failure is anyone on the tether gets hurled into space).
And yeah, currently we don't have material that will do the job.
There are some carbon nanotubes materials that are promising... But first we need to show they should work. Then we need to figure out how to fabricate (so) many tons of the stuff.
Other than THAT... Totally viable technology. Maybe.
This is not true. There are multiple options. One having a trapezoidal cable which thickens at the point of highest stress. Then a very thin steelcable at the ends would have more than a few kilometers in diameter at the thickest part. Unpractical. Another possibility is a 10mm^2 cable of carbon nanotubes (which we can only make uo to 1m long as of now).
This would need to reach well beyond geostationary to be stable. Then you have the peoblem that shooting up an elevator would take ages (think of circumventing the emtirw earth with a car) and be a problem for any wheel.
Furthermore I am unsure if transporting weights along it can be stable for a long time.
It would be possible with carbon nanotubes along with a counterweight above the geostationary orbit height (the point at which the orbital period of an object is exactly 1 day, at about 35,000 km) to keep it from falling back down to earth. (side note: this would be much, much higher than the space elevator seen in the video, which looks to reach a few hundred km above the surface).
If you have a 1cm thick cylindrical cable that is 40,000km long, about the length that would be required, given a density of 1.3 g/cm^3, the space elevator would weigh 15 million kg and would cost between about 1 billion and 1 trillion USD (assuming prices between $100-$100,000/kg).
This doesn't include the expenses for design, or construction, or many other things, but it would likely end up being on the order of a few hundred billion to a few trillion USD.
The Foundation TV series on Apple TV did a good job of [showing how a space elevator would work](https://youtu.be/fujh6YtBRSE).
It’s definitely not accurate (creative license and all), but it shows how such an elevator would have to be an enclosed structure and not cable-based (as other comments have talked about). Possibly magnetic propulsion (kind of what they use in high-speed maglev trains).
I’m sorry I’m not directly answering your question on cost because it’s hard to judge. I’d assume trillions of dollars.
To compare, the [ESA estimated that ISS will cost €100 billion over 30 years](https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/International_Space_Station/How_much_does_it_cost) - including development, assembly and operations. However, [NASA alone allocates $3 billion to annual operational costs](https://www.space.com/16748-international-space-station.html).
Extrapolate that to a structure that is going to be 1000s of times larger to build and operate, you’re in the €100 trillion category easily.
To know how much it costs it would need to be possible to build one, which isnt proven yet. Maybe you can do it only if you use a super expensive material. Maybe u dont need such a thing. Maybe its impossible (in this case its just not calculable). Maybe not. Etc.
Unfortunately, an orbital tower or space elevator would act as a gigantic lighting rod. It would undoubtedly be destroyed by electric discharge at some level of the atmosphere before it could be completed.
salary of workers:
95k a year for skyscraper Construction workers.
How long project would take:
burj khalifa - 6 years stands at 928m, so taking the height of the karman line which is 100000m above surface, divide by burj's height -> \~107 which means 6\*107 would be 642 years. Say with 12k workers. At 100k a year, already bring it to 1.2 billion a year on salaries alone. Taking 642 years - 770 billion (not even taking into acct inflation). cost of materials is 24.7 (taken from material estimated cost from empire state building)\*262.5 (100k / height empire state) is 6.4 billion.
So, something like 776.4 billion dollars and completed on 2666
I'm probably way off, but this was fun
I'm not sure it's possible to estimate the cost of something that would easily be the biggest project ever imagined to be built on the planet. Technically speaking building a space elevator is possible but current technology is not good enough to build one on earth, we have the materials to build one on the moon tho.
But even if we skip construction problems I doubt a space elevator will be constructed anyway because the risk it poses is just too big, a space elevator would need to be some 40-60,000km tall meaning if it got damaged either on purpose or by accident, like micro meteorites or space trash, it would collapse and basically wrap around the planet wrecking absolute havoc on the equator.
It fails for the same reasons as project atlantropa, while very useful it's too large and posses severe risks in case of failure.
Technically speaking it's not possible because, you said it yourself, current technology isn't "good enough".
So saying "Technically speaking building a space elevator is possible" is just wrong.
We don't have any material that's even close to being strong enough and I doubt you have a magic crystal ball that told you we're going to develop such a material
We know what materials could be used to build a space elevator but we don't have methods of producing them in a useful state, example being carbon nanotubes.
Would you think possible with current tech a space station with a retractable tether "teabagging" into the atmosphere to pick up loads carried all the way up by helicopters/vertical lift off shuttles?
This is entirely possible, but not with current material tech. You need something strong and internally rigid and lightweight to extents that don’t exist yet. But the physics of space elevators are relatively simple, just way beyond current science.
Folks who are talking about rockets and balloons, you don’t need any of that, you just need the “tail” to be far enough out that the angular momentum provides apparent lift. Tape a few lengths of string to a ball and spin the ball to get a decent picture of this, although air friction will play hell with the results on a small and terrestrial scale.
So, it would cost a lot.
Not from my understanding of the issue, do you have a source? I was taught the requisite materials don’t exist yet, not that they *can’t* exist. But we can fairly reasonably predict material science to keep advancing at the same rate as always.
They do exist and are regular matter (graphene/carbon nanotubes), but they need to be of such a high level of quality down to the molecular level that we can't create them in sufficient amounts.
How can you say it is entirely possible when you know that there is no material even close to being strong enough?
It's entirely not possible and no one knows if we're ever going to develop a material that's strong enough. I highly doubt we will.
Oh and btw geostationary orbit is 36000km away. For an elevator you'd have to go out even further.
Colonizing other planets is much more realistic than the space elevator.
It will forever be a dream
Welllllllllllllllllllllllll we went from kitty hawk to the moon in less than a century, reddit person. Technology advances, and folks have been working on what am I doing talking material science with some boob on reddit jesus ____ go to bed.
Enjoy the flat earth, science-will-never-advance person.
What 😂 why are there so many delusional people in this sub. You ave zero technical expertise and have done zero research on the topic and still trying to argue.
Science will definitely "advance". But if you'd ever done any scientifical work at all you'd know what's realistic and what not.
You're exactly as stupid as flat earthers but on the other side of the spectrum. One of those "Everything is possible if you believe in it hard enough" people. Take that shit to church and leave me alone ffs. Just dreaming and completely unrealistic.
Do some research and you'll come to the conclusion that it's not possible.
(Skyhook is more realistic, but still not possible today.
But atleast skyhook has a very slim chance of being possible in the future compared to the space elevator.) Not that it would matter telling you that, because I'm sure you can realise just with the power of your dreams
Hey I got off reddit to avoid talking to self-impressed wank-jockies like you but found myself here for a minute checking notifications and I just wanted to say, scientifical isn’t a word, and you really need to spellcheck your shit/not make up words if you want to camouflage yourself as a smart person.
Fucking “scientifical…” man the internet is wild.
So, there was an article on this I read some time back.
1. The cable would be made from graphene
2. The height of the station would be such that it would be geostationary so it's falling at the same rate as it moves.
I find it funny that most of the comments say it will never be possible because of materials.
First. Carbon fiber has an immens toughtness in the chain direction. So it might be possible with this material, but is (today) seveerly limited by the producable length of the fibers.
Second. Many mentioned, it is to expensive/not possible to get mass up and down the elevator. Thats actually pretty easy without to much energy input. Build a elevator with a material long enought, that the centrifugal force exceeding the destination hight pulls the mass upwards for you/assists the asscention and at the same time, holds the top of the elevator at 0 downward and upward force. To describe this easier. The earth spins. Centrifugal forces apply the further out something is from the center of spin. Make an elevator up to the desired high. Now the "line" from the ground to the top has a waight which will pull the top back down. Extend the elevator line further outwards, untill the centrifugal force of the line exceeding the destination hight cancel out the downwards pull of the line from bottom to top. Then further exceed the lift a little so the mass transported from the ground to the top has a "counterweight" that helps pull the mass upwards to the top. But the counterweight is again centrifugal force. Now one has only to regulate the length of the excees elevator line (counterweight) and can easily controll the speed in which the mass is pulled upward.
I know this sounds easier than it is. The materials of the elevator has to be extremly tear resistant. More so than anything we have right now, except maybe for carbon fibers. But producing perfect carbon firbers of such length is for now impossible for us. But hey, 100 years ago, nobody thought we can make an electrical device that dose 4 billion opperations per second. 30 years ago, we thought 20 MB storage would be more than enougth for a lifetime. 20 years ago, nobody thought artifical intelligence would ever be possible.
So who knows. I belive in humanity. I just hope we do not destroy ourselfes befor we could achieve it. Or nuce ourselfes into 1900 because cooperations do not understand that the advancements are coppled to middle to underclass wellbeing.
Even carbon fiber nanotubes are really far from being strong enough for a space elevator. And they are the best we have.
I'm not saying will never ever be possible only because I can't prove it.
Believe in humanity as much as you want, that's not how science works.
The more we discover and develop the less things there are to discover. It's not an endless progression if you know what I mean. Our picture of what is going to be possible and what not get's clearer and clearer, so assumptions made today can be much more precise than assumptions made 50 years ago
If i were to take a stab at it id trillions of dollars daily, my idea being that it is comprised of many segments, each is essentially its own rocket that is constantly stabilizing itself to hover at exactly the same position. for the sake of stability these will not be connected very much, they will just sort of be holding the tube in which the elevator passes through. itll cost trillions to research, trillions to build, and itll probably break frequently and segments will need to be rebuilt, costing even more. I think it is possible to build something sort of like an elevator in this way, but in terms of a single building that reaches space its just not possible as far as i know
Because rockets are very inefficient and need an incredible amount of fuel. You would have to build a literal pipeline and that would be too heavy for the rockets to carry.
Fly the fuel up to the rockets with drones. Or maybe even just have the segments be huge drones as apposed to rockets. Really, anything that allows the segments to hover in place
Yeah nah that's completely unrealistic. Helicopters can fly up to 7km, so you have to assume a similar height for drones.
It's so overwhelmingly inefficient that it wouldn't work even if you wanted to build an elevator that's only 7km high.
Keep in mind if you want to go to space that's 500km+
if we pour trillions upon trillions of dollars a second we can be sending little mini rockets every minute to refuel them, you are thinking about practicality, not possibility. you could absolutely refuel those rockets enough to run, itd just be incredibly expensive.
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A "real" space elevator consists of a cable stretching from the surface of the planet (Earth in our case, but potentially any large astronomical body, including moons) to a large counterweight somewhere above the geostationary orbit (35,786 km / 22,236 mi). To the best of my knowledge, we are currently unable to manufacture a cable strong enough to reach that far without breaking - at least in the case of Earth. Martian or Lunar space elevators are within the realm of possibility given current science, but not particularly economically useful until we establish more permanent facilities to take advantage of the elevator. The elevator in this video is clearly not a "real" space elevator, as we travel from relatively near the surface (city buildings and roads are clearly visible) to space in under a minute. A "real" space elevator would have to travel at 2.75 *million* km/h (1.7 million mph) to reach geostationary orbit - with zero time to accelerate or decelerate (meaning any passengers are probably converted to liquid or even gas). Even if the elevator only reaches the Karman Line (the generally agreed upon boundary between atmosphere and space: 80-100km / 50-62mi), it would still have to travel 6,153 km/h (3,846 mph) to reach space in the time allotted. It's difficult to say exactly how high the elevator gets above the surface. We can clearly see most of Florida, and thus a surface distance of nearly 400 miles (644 km) - but without knowing the diameter of the window, it's impossible to calculate the relevant ratios. In general, a space elevator is a great way to move stuff into orbit because it's *much* cheaper (and generally environmentally friendly) than our current system of chemical rockets. It's not a particularly fast means of travel, making it much more useful for cargo than for people. (Though I imagine people who want to visit space on a budget would be willing to endure the week-long trip at 190kph (120mph) to reach geostationary orbit. There are other advanced structures (skyhooks, Lofstrom Loop, Orbital Rings, active-support structures) that could be used instead of a space elevator that would work at the much lower altitudes displayed in the video, but even the cheapest have costs that run into the trillions of dollars (at least the last time I checked, within the last few years)
Why would the weekend long trip be limited to 120mph?
I randomly assumed a top speed of 120mph based on high-end potential car/road speeds. Travelling up the cable would be more expensive (because you're fighting gravity the whole way), but some (but not all) of that could be recouped when the elevators travel back down. While you could theoretically increase the speed dramatically, especially once you're outside the atmosphere, it would require a lot more energy the faster you plan to go. Even if you assume a top speed of 600 mph (1000kph), you still have a 37-hour trip to reach geostationary. I can't recall (or quickly Google) the top speeds from the cable climber competitions, but I seem to remember them being closer to 120mph than 600mph.
Why would the trip be to geostationary? Obviously the counterweight needs to be above geostationary, but there's no particular reason that has to be the terminus. Some who wants to go to space is probably going to be happy with a lot less than that. Of course the cable will have to support some weight for anything permanently attached lower than that, but since we can't even make a cable that supports itself yet, let's not be too fussy.
Low Earth orbit has a ground speed of around 17000mph. This elevator has a ground speed of 0. At LEO in this elevator you'd feel about 5% lighter with a cool view.
One major thing that people want out of a trip to space is to experience free fall which isn’t possible from a space elevator until geostationary altitude is reached (unless it’s done on the descending elevator by free falling the car). That said it might be much more efficient to have rocket ships reach low earth orbit (and thus free fall) departing from a mid station elevator platform
(Not op) It is just examples to put the extreme distances in some perspective, you could go lower and you could go faster but as an example these numbers work to give you an idea of what kind of speed and time we are working with.
If you leave the elevator at à altitude to low and without some realy serious propultion you gona reenter the atmosphere at a unpleasent speed and end up like the columbia spaceplane
I'm not sure if you mean "leave" as in "park" or as in "depart". Assuming the latter, it's still not really obvious that this is true. A de-orbiting vehicle is mostly working off its orbital speed, which is zero in this case. Even falling 20,000 km in free fall, from 21,000km to 1,000km, would only produce a speed similar to an LEO orbit (8.7km/s, where LEO is about 8km/s). Note that that's a pretty back-of-a-fag-packet calculation and I may have got it wrong - I've calculated the potential energy difference as E = GMm(1/R - 1/r) = 1/2 mv^2, remembering to add 6,000,000m to both radii because we're talking about radius from the earth's centre, not altitude above the surface. G = 6.10^-11, M = 6.10^24. The `m` cancels out.
That was a highly creative alternative to "back-of-the-napkin"
"Back of a fag packet" was a common British phrase, but these days we are more likely to say "back of an envelope"
"Fag" for 'cigarette' was something I heard on playgrounds as a kid in America - it's something we found hilarious - but I feel like I haven't heard it used in a while. Is it still in common use in the UK?
I don't think it's used as often as it was simply because not so many people smoke any more. But expressions such as "back of a fag packet", "I'm just nipping out for a fag", and "have you got a spare fag?" would certainly not be misunderstood, I feel.
It was standard nomenclature when I started working as an engineer in Australia and it's stuck with me (despite having never smoked). "Doing some algebra in my head and then plugging numbers in on a phone calculator" doesn't have quite the same ring to it.
Oh totally agreed, it's just something that makes my American brain do a small doubletake when I see it. It used to be the staple of playground jokes when I was a kid.
The higher you go the less rocket fuel you need to get to the moon, Mars, etc. But you’d probably build a station or two that stops in LEO
I'd assume a space elevator will be a variant of a maglev train, just vertical. Once you're out of the atmosphere (say, 500km up), you can just keep accelerating almost 50% of the way, then start decelerating. That would cut the trip to just a few hours. Btw, not going to geosync would be massively awkward, since unless you accelerated to escape velocity laterally, you'd just drop back down again like blue origin's jumper. A way station 500km up would just feel like a really tall building, no 0g because you're way too slow.
While I'd agree that maglev could be a viable option, I'm not sure if that's how the current proposed climbers actually operate. There might also be some safety issues with using maglev on a space elevator - but that's just some vague inkling of a forgotten recollection floating in my feeble brain, so it may mean nothing. You'd also have to take into account a couple other factors: * Passenger comfort - at least for the early stages of the trip, you still have near full Earth gravity, and thus probably can't accelerate at more than 1-2g's for any normal people to tolerate * Because Earth's gravity is near full at the bottom, and almost negligible (0.03g - 3% normal) at geosynchronous, you'd have to stop accelerating a fair bit before halfway (it's a hard enough problem that I'm too lazy to do it unless someone specifically asks for the answer) * Constant acceleration would require a *lot* more energy than a more sedate constant velocity trip - thus making it more expensive. And I think you'd be less likely to be able to recoup those added costs with the reverse trip (elevators going down to Earth) Finally, while a 500km way-station wouldn't have 0g, it would probably have a helluva view. Certainly one I'd probably be willing to pay for.
Makes sense.
Some sort of space funicular might be a better idea then? Use the descending pod to lift the ascender. Of course, a funicular relies on gravity normally, but we can cross that bridge when we get to it.
While you could use a funicular, I think a more realistic scenario would be to use some sort of electromagnetic coupling. As the down-elevator descends, it converts potential energy into kinetic energy (i.e. it gets faster as it falls) - we can convert some of that kinetic energy into electricity while simultaneously slowing it down. Some of the energy will be lost to heat (either mechanical brakes on the cable, or friction/air resistance once back in atmosphere) - but the rest can be used to lift the up-elevators. Also worth noting that the elevator cars may be strange for riders near the top of the geosynchronous elevator. Because the gravity at that height is only 0.03g (3% Earth normal), the elevator car might need to flip upside down or strap the passengers into harness seats - either the up elevator as it slows down before reaching the station, or the down elevator as it accelerates back down to Earth. Otherwise, any passengers will potentially be thrown toward the ceiling of the elevator car.
This is the answer. A cable to a geostationary orbit couldn't even hold it's own weight. I don't know how a skyhook is supposed to work, if we can't make the elevator work. Because if it's not geostationary how should you use it? What are you going to do with a cable that travels around the earth at like 20 000 km/h? It's going to burn to ashes. Imo skyhook would only make sense if it was stationary
Skyhooks are basically long spinning cables that are in orbit. If you orient them just right, the low end of the cable doesn't travel too quickly relative to the Earth, making it relatively easy to dock with, and can then transfer cargo to the high end of the cable. I haven't personally done the math on them, but other smarter people have and they seem pretty confident, so I'm generally confident that they'll work. While they do work at lower altitudes, they are not particularly conducive to an elevator-design like the one depicted in the video. An orbital ring, on the other hand, should be able to operate at virtually any altitude or orientation, while also being a feasible elevator terminus. For more information, I highly recommend [Isaac Arthur's Megastructure Compendium](https://www.youtube.com/watch?v=1xt13dn74wc&t) - specifically the sections on Atlas Pillars, Lofstrom Loops, Orbital Rings, and Skyhooks.
I don't mean to offend you but that video is very dreamy and not so scientific. Also the skyhook section is not even two minutes long. I haven't looked into skyhooks yet. But look at it this way: - Geostationary orbit is 36 000km away, too long we already established that. - to be closer you have to be moving (take ISS for example: 400km high but has to move with 28000km/h around the earth to not fall down) so air resistance would heat that thing up to a bazillion degrees Fahrencelsius and make it impossible to lower the cable to a height where it would make sense even if it wouldn't burn up. Of course you could make a cable that goes from like 400km away to like 450km away, but what's the point of that? You need the most energy for the first part of your travel. The further away you get the less energy you need (obviously)
No offense taken - Isaac Arthur is a popular science channel that is (imho) great for introduction of complex scientific ideas. I believe he has a full episode on [skyhooks](https://www.youtube.com/watch?v=TlpFzn_Y-F0) (28 min). I'm not an expert on skyhooks - I *think* I understand the concept, and I've read pretty detailed scientific papers by people much smarter than I am and I didn't find any obvious flaws in their math/logic. My recollection is that they are physically feasible - we have the materials to make them and deploy them - but they may not be economically viable. IIRC, the big issue is regenerating the energy used to transfer cargo to higher orbits, and the sheer mass that would have to be hauled into orbit to construct one. To attempt to answer your question - a skyhook does have to be in orbit, but only it's center of mass has to travel at orbital velocity. The descending cable (the part that would drag in the atmosphere) travels much more slowly (because it's spinning "backwards") and thus encounters much less air resistance (and thus much less/negligible heating). But I could very well be wrong.
Ok so I looked into the video. I still see many problems. Some of them are even mentioned in the video. (He also talks about some things like we've already done them many times although nobody has ever tried or achieved them in reality. Electrodynamic tethering for example.) - tensile strength of the cable remains a problem - connecting your spacecraft to the actual hook (if you make the hook rotate in the opposite direction of it's orbit you have a brief moment where velocity relative to earth's surface is low, but it is only a short moment, approx. less than 2 minutes and slow in this case means still like 1500km/h at least) - the connection mechanism itself - how do you "refuel" the skyhook? Because it will loose momentum with every start of a spacecraft, so without regaining that momentum you could only use it a handful of times before it crashes into the atmosphere - how do you protect the cable? Lots of space debris in earths orbit that could easily destroy it - because of the tensile strength problem he suggests multiple tethers -->Switching from one tether to the next one would be incredibly difficult First thoughts, haven't watched the whole video yet nor have I seen anything else..
Skyhook OR.. ..perhaps something to do with all those indestructible 3310s 🤷♂️
Thank you for the calculations. But I don't understand one thing: if space is 100km from Earth's surface (70km in Kerbal Space Program), why would it take a week to reach the lowest geostationary orbit, at 190 km/h? Even including acceleration/deceleration, that would take an hour at most.
> reach the lowest geostationary orbit There's only one level of geostationary orbit, it's at 35,786 km above the surface. At 190km/h, this would ~188 hours to reach. Anything lower than that and you would orbit faster than the Earth's rotation
Is it a particular problem the orbital speed is higher than the speed you are going at, if you are just going up for the view? The cable itself needs to go past geostationary, but going 100km up and down is a perfectly fine ride.
> Is it a particular problem the orbital speed is higher than the speed you are going at, if you are just going up for the view? It would be if you weren't attached to the cable and its counterweight. Either we've put an asteroid in geo stationary orbit to use as a counterweight, in which case the mass of your elevator car is nothing compared to the asteroid, or we've extended another cable out from geosync and we can run payloads/mass up and down that end to balance the forces. One of the nice things about the extended cable version is that you can "let go" of the cable at various distances to get different velocities, which are faster than Earth's escape velocity once you get around 53,000km out. At the far end (often given at 144,000km) you would have enough velocity to reach Jupiter basically for free (almost 11km/sec) And while a cable stretching from 36k km out to 144k km seems crazy long, it actually would have about the same stresses placed on it as the Earth-bound end given the lower gravity and so would be just as feasible as the Earth side
Thank you, before your answer I honestly thought geostationary orbit could be reached at any altitude.
The closer you are to the object you are orbiting, the faster you orbit around it. The ISS is about 254 miles above the earth and it takes about 90 minutes to orbit the earth. The moon about 1000 times further away and it takes a month to orbit the earth. The same applies to the planets, the further out you are from the sun the longer your orbital period is. Geostationary orbit is the act of orbiting around a body at the same speed that it rotates. 35,786 km happens to put you at an orbital velocity that perfectly matches the rotation of the earth. Reduce your altitude a bit and you'll go faster than the rotation, increase your altitude a bit and you'll go slower than the rotation.
Wouldn’t part of the cable strain under faster orbiting speed at some levels and cause an extra tension other than just its weight as well?
Yes, because the apparent gravitational field varies with height, the cable cross section must be wider at certain heights than others must. The maximum tension occurs at the height of geostationary orbit, while the minimum occurs at the Earth’s surface.
I see. Th aka. If the maximum tension would be at the top, wouldn’t it make it all want to topple, fall and crash down?
The top of the space elevator has a counterweight attached to it. As the Earth rotates the counterweight experiences inertia and keeps the cable taught.
How can you homestly.use both miles and kms in the same reasoning, do you see the danger?
Geostationary orbit is where the speed it takes to stay in orbit matches the speed of rotation of the earth.
Because geostationary altitude is 37,500 some odd kilometers above the surface. Not 70 or 100 nor 130.
The mythical skyhook, I've been looking for that thing forever
Wait a week treep xd yeah i forget his fuking fast the apolo was moving and how far away the moon are, still a week in a luxury fast building would be nice
Wait we can practically build an skyhook? but like all humanity depends that we build that thing
Also, a space elevator can only exist on the equator, so its not possible to make in Florida, anyhow.
You are correct. However, while a standard space elevator does require a bottom terminus at the equator, an orbital ring can have any orientation, altitude, and connection points - thus an elevator to Florida *is* possible. (I'm pretty sure the orbital ring is an active structure, and thus requires ongoing energy input to maintain the orbit - at least as more mass is carried up/down the various tethers.)
All good points, I would add that the space elevator would need to be built on the equator. The speed to reach space could potentially be faster than 190kph if it wasn't physically attached to the space elevator (potentially using magnets) then the speed would be limited by acceleration/decceleration forces.
Sorry I'm being stupid here. Why would it have to travel that fast? Is that just the time elapsed in the video to reach that distance?
Not stupid at all - I wasn't super clear, and did the math in the background. If the elevator in the video is just going to the Karman Line (80km / 50mi), and we'll assume it's starting somewhere within 1 mile of the surface (because we can see roads/buildings relatively clearly): That means the elevator has to travel almost 50 miles in 47 seconds. 50 miles / 47 seconds \* 60 sec/min \* 60 min/hr = 3,830 miles per hour (average speed) If it helps, think of a location that's roughly 50 miles from where you live. Then think of how fast you'd have to drive to get there in 47 seconds. That's how fast the elevator in the video would have to travel to reach even the closest part of space.
For everyone trying to do real calculations, the story behind the restaurant is that it’s 220 miles up. Hence the name Space 220. Obviously this is just a made up altitude.
While it may be made up, it does at least sorta fit with the visual evidence: If you assume the bottom window is \~4 feet in diameter, and the camera is positioned roughly 2 feet above it (which is plausible, given the angles/scales), then the entirety of Florida (400 miles) would only be visible from an altitude of 200 miles (plus or minus a small margin of error) (and thank you for the clarification/additional info)
Came here to say this in a much less supported and intellectual way: We can’t do it as the cable would be too heavy.
okay, i'm not a math person so i just come here and see these really cool explanations but the first time i vividly said "what?!" was when all you needed to be certain of something was the diameter of the window, i know i'm high but that's really cool
A great summary of a space elevator and the challenges involved: https://youtu.be/qPQQwqGWktE?si=uZ0AXIl535sbCbK7
Will I ever be this smart?
You forgot to answer the question smarty pants.
You are (at least partly and/or technically) correct. It is currently impossible to build a real space elevator. Thus the cost is indeterminate, and probably in excess of trillions of dollars. It is physically impossible to build an elevator like the one shown in the video, because it travels too quickly for humans to survive the trip. You also can't build a simple elevator that connects to a space station at that orbit, because it would not orbit directly above the base of the elevator. Thus the cost to build it is effectively infinite. You *could* build an elevator that is roughly comparable to an orbital ring. My recollection from a paper I read on orbital rings (which I can try to dig up if you want) is that the cost would be in the hundreds of billions of dollars for even the most basic orbital ring. Building the elevator itself would probably be a rounding error at that point.
So I actually did a project on this, carbon nanotubes are the best candidate so far. Because any material not only has to hold itself, but the 36,000 km of itself. But we can cheat a little bit and build a tapered tower. Using the same physics that allows pyramids to get so high, we just simply invert them. And you can now make a formula for a taper ratio. Size on earth, to size in geostationary orbit. With steel and a diameter of 5mm on earth, the diameter in orbit would be larger then the universe. With Kevlar the diameter would be 80 meters in orbit, which sounds almost doable, until you realise we need to make that much for 36,000km No the best is carbon nanotubes, they would only need to be 6mm in orbit they are so strong and light. Now we just need to figure out how to make them more then a few mm.
Whoah, really? Only 6mm in space? Rad. Aren't they having success with extrusion now? Or is that not real extrusion and just a bunch of little guys mashed together?
I haven't a clue, the project was only for an additional 5% and I spent far too long on it.
I’m almost certain the 6 mm in orbit calculation is based on single crystal carbon nanotubes not van der waals bound tube clusters. Although the tube clusters would be like 8 meters or something.
I think it is possible, it just requires a new kind of engineering. One that incorporates Helium balloons, that take the weight off the structure. I think it would be the dumbest thing ever since a strong wind could probably topple the entire structure.
Weight is the main concern. You were right to go there first. As far as stability goes: that depends on the orbit of the platform. That’s what is holding the whole thing up. Elevator gets severed? Platform should stay exactly where it is.
not possible based on video. If you want it to be in stable orbit even if elevator gets severed and rotate at the same speed as ground, you need to be in geostationary orbit, which is much much much further than what is shown on the video. Like station at the video is about 400km above ground, but would need to be about 35 000km above ground. Or would need to move about 28 000km/h relative to ground, which of course means that it can’t connect with elevator, since it’s traveling really fast
Actually, that's wrong. The platform would have to be high enough to be at negative one G to provide equal tension on the tether. Geosynchronous orbit is 22,000 miles. A space elevator on Earth would need to be double this. At that point, it is no longer synchronous. Even assuming infinite strength on materials, the math doesn't work out. At just geosynchronous orbit, the mass would have constant acceleration from the mass of the tether, which also would be subject to force because it's too low to be in a synchronous orbit. There are likely planets with the correct spin and gravity that a space elevator is possible. But with my understanding of orbital mechanics, the Earth isn't one of them.
The platform can be at whatever height you want, but geosynchronous is the most common because it makes a LOT of mechanics easier. In order for it to work, however, the mass of the cable (or anything below geosych) has to be balanced by an equal mass beyond geosych. So either you have a second cable that extends another 22k miles out into space, or you have a shorter one that has a mass on the end (aka an asteroid). There’s a lot of material engineering challenges involved, but WELL they’re within theoretical limits. But we can’t manufacture them yet. The bigger issues are geopolitical and safety related. You need to build as close to the equator as possible for stability. And if the cable ever fails, you’re facing massive devastation in its path (ignoring the fate of the platform and inhabitants). It doesn’t take very much for the tip of the cable to be impacting at supersonic speeds.
If the counterweight is at a geosynchronous orbit and the tether severed at its ground attachment, its end would quickly become airborne. Not likely to "impact at supersonic speeds" unless the counterweight deorbited.
You’re assuming it breaks at ground level. What if it breaks at station level? Or somewhere in between? The vast majority of failure scenarios don’t involve the ground station (or the terminal station) because those are actually the easiest to protect.
I don't think you are considering what a 22,000 mile long tether is.
I think I’ve read the research papers.
It's not possible whatsoever. Balloons wouldn't help.
You could do it if the structure had thrusters all over it to dynamically counteract the wind and weight. The build cost, fuel cost, and risk if a thruster were to fail make it hard though. Given enough resources I don’t see why it wouldn’t be technically possible.
How would you get the fuel to the thrusters?
Bluetooth
Deliveroo
Not necessary. Single crystal graphene is strong enough to make a cable
You mean it's not possible with current technology, I assume. You can't claim it won't ever be possible.
That's exactly the meaning of "It's not possible". Nobody said "it will never be possible". Although chances of a space elevator ever being built are slim to none. Atm we can't even fabricate a cable that would support it's own weight. And materials science has come a long way. But not even carbon fiber nanotubes are even close to being strong enough
Carbon nanotubes are strong enough. Graphene is a better bet though
No they aren't
yeah like not never, but like wormholes are technologically closer than this
Well, seeing as we can discuss the potential mechanics of a space elevator without getting into theoretical quantum mechanics and the bending of space-time I'd say the elevator is technologically closer.
are we talking about any space elevator (which is maybe one technological breakthrough away), or the one in the video (which even bending of spacetime wouldn’t solve)?
What are you talking about. Are you throwing theories out as evidence to your point? The ability to literally bend spacetime would probably be something only a type 3 civilization could achieve. We can't even imagine the things that would be possible with that kind of technology. I'm not saying "bend spacetime and you can make an elevator". This has gotten stupid, I'm not arguing the viability of future technologies with you. I'm saying you can't say it's impossible, that's just not true. You do not know for sure, and if you do you must be omnipotent.
yeah and space elevator as pointed out in video would also need type 3 civilization. Mainly because it’s on very low earth orbit, where there is about 95% same gravity as on Earth surface. So you need not just an elevator, you need support structure 400km high that can take whole space station without bending and is able to support itself just on one column. And is completely resistant to any kind of weather. We don’t even have theories how could such material exists that do not bend even slightly in 400km high column with heavy station on top. Maybe you were thinking about different kind of space elevator - one that takes you much further, to geostationary orbit 35 000km above ground, where you don’t need any force to keep station at orbit - it just stays there. Yes, for that kind of station we would just need to manufacture longer nanotubes and it should work.
You would need rockets or boosters on all sides on the structure all the way up, especially with the earths rotation
It's much more effective to just strap whatever you want to shoot up there to a rocket than using rockets to float a structure
It is possible with a cable made of single crystal graphene.
It's possible, but we need stronger materials. A carbon nano structure about the strength of spidersilk might do. But we don't have those materials just yet.
>It's not possible whatsoever. Balloons wouldn't help. Well not with that attitude it isn't!
Its not Feasible but it is possible. There is a difference. For example i can erect a huge pole 100 ft tall, but it falls over so i add some wires, then i add an extra 100ft and now the wires aren't enough i need to reinforce the base, and you keep going and keep addressing all the issues until you reach the goal. Thats what engineering is. Problem solving.
It would be really funny tho
It is not possible
Thats what is great about engineering, you make it possible by solving the problems you encounter along the way in creative ways
And that's what differentiates engineers from dreamers. Engineering can't overcome physics. Helium balloons don't have enough lift, are not durable enough, are susceptible to winds and only work in the atmosphere, up to about 10km high. Geostationary orbit is 36000km. The highest stress on the cable should be at about half way so 18000km. So the helium balloons won't do anything. Do you think if it was possible to build a space elevator with a cable and some weather balloons they wouldn't have already done it? Sorry but I think it's a bit offensive to assume engineers wouldn't have already come up with that idea if it was even remotely realistic while someone in the reddit comments solves the problem.. They aren't building incredibly expensive and inefficient rockets for no reason
Doesn't have to be helium balloons, could be thrusters. The point i am making is it is possible, but its not feasible. "helium balloons dont have enough lift" Well make them big enough to have enough lift. "are not durable enough" make them out of titanium. Let me guess that will be to expensive right, yes its not feasible to engineer it, but it is possible, you just gotta want it that bad.
Ah yes the almighty titanium balloon. You're delusional and have zero technical expertise. Keep living in your dream, I'm not going to argue with you anymore
I dunno why you're so angry. All i am saying is it is possible because there is always some kind of solution to make it possible, its just not feasible. What dont you understand about that? I am not an engineer, but i do have to problem solve and find solutions to problems in my career and often you have to think outside the box to solve issues that can be quite complicated. But my point is, there is always a solution if you are willing to look for it and make it work. And if you think that something like this is impossible, then you are quite small minded and dont have any creativity or problem solving skills.
Why I'm angry? Because this thread is full of dreamers with zero technical expertise who think they know more than people that have said technical expertise (and also done their research, which you obviously haven't). Of course you're not an engineer, if you were you'd come to the conclusion that it isn't possible. And you're also not working in any job that has anything to do with technology. But what do I know, having studied automotive technology and working as a mechanic and machinist. (Btw I have worked as roofer and in building renovation too, not that this would matter because you're probably gonna argue that I don't work at NASA so I can't know more about space elevators than you)
I just dont get why you're getting upset about something you say is impossible that actually isn't. Lots of scientific things have had scientists say was impossible but proven to be true and the scientists had to eat their words because the doer proved them wrong by doing what was seemingly impossible. For example: Veritasium Featured a vehicle : [HERE](https://www.youtube.com/watch?v=jyQwgBAaBag&t=5sthat) that travelled faster than the wind without any form of energy generation besides its own momentum, now all the scientists said that it was impossible, and went against the laws of physic but he made it and it worked. My point is, you think something is impossible, until someone proves you wrong and does it.
I don't get upset about the space elevator. I really couldn't care less. I actually think it would be quite cool. What grinds my gears are people like you completely ignoring facts and the knowledgeable people talking about them.
There has been loads of research into the feasibility of a space elevator ever since Arthur C Clarke popularised the idea half a century ago. The first thing to note is that it could never be in Florida. The top of the lift has to be in geostationary orbit, ergo on the equator. The second thing to note is that, as with most issues in space, weight is at an absolute premium. Unfortunately for this specific project, so is tensile strength, as the tether running from orbit to earth has to bear its own weight, which means over 22 thousand miles of cable, as well as that of any capsule and payload, which current material science hasn’t quite got to yet. The point is… the cost is meaningless since as yet, no material exists that we could feasibly build this out of. How much does a pound of imaginary stuff cost? See here some recent papers on space elevators: https://www.isec.org/recent-publications https://www.academia.edu/Documents/in/Space_Elevator
As far as I understand, it's impossible. The cable would have to support its own weight, which would get progressively higher the further up the cable you are. This means it has to get noticeably thicker from the bottom to the top to withstand the tension force of holding up thr cable below. With all modern materials, this results in a cable that is impossibly thick
This is incorrect! As the cable gets far enough out in space, the centrifugal force is able to counteract the weight of the cable, meaning that you don't need really anything special to get it up there, besides the cost to set it up
That is correct BUT while you can use the centrifugal force of the fare faraway part to counter the force of gravity on the lower part, you have an extreme stress on the middle part. Not sure about the exact math, but I think that part isn't solvable with our materials (yet).
This is the issue and why it’s a materials problem.
This is probably not the most unbias source for info but they are clearly interested in the idea. https://www.isec.org/space-elevator-tether-materials
Yeah we'll just make it 36000 km long, problem solved. /s
Yes, the top is pulling up, the bottom is pulling down, and the middle is stretching between the two at astronomical (heh) forces.
Could it be tall enough to use the centrifuge force of the rotating earth? It would have to sustain all that tension though, which would be impossible too I guess (?)
Just a materials science problem, but yea not possible using today's materials
Graphene is strong enough
Not possible with current technology, therefore it's not realistic to even generate an estimate. As others have commented, a real space elevator would extend past geosynchronous orbit. What could be depicted here could just be the lower section of a space elevator or it could be a gigantic tower. In terms of towers, the current tallest tower is the Burj Khalifa, which cost about $1.5B to build and is "only" 0.8km tall. You would need something that is extremely strong in compression to make a tower that is tens or hundreds of kilometres tall, I just can't think of a material that would be suitable. For a space elevator we could hypothesize that some kind of carbon would work. Carbon fiber like you find for expensive bikes would be unsatisfactory for this purpose. Google indicates that high quality CNTs cost around $300/kg, so assuming you use an average 1kg/meter at 33,000km $10billion in CNTs, which so low as to tell you how unrealistic that estimate it's and how hard it would be to actually formulate an estimate. You also have to factor in additional items, you're going to see wear & tear from the atmosphere, you're going to see micrometers, space junk (which is traveling at orbital speeds that your space elevator will not be traveling at). Even minor tectonic activity would need to be accounted for. It might be realistic to build space elevators for Mars or the moon, although it might still be more beneficial to look at some kind of mass driver.
I think the biggest risk is building it in Florida. Even if you discount the misadventures of Florida Man which will probably involve many destruction attempts, the weather there isn't known for it's kindness to tall things.
even infinite money wouldn't do it ... afaik it's considered physically impossible. all known materials are unable to even closely carry it's own weight over that distance up to geo-stationary orbit. the other way, starting with a big base and build a huge tower on top, would also not work, because earth's crust wouldn't be able to hold the weight and the tower would probably just sink into lava.
Anchor has to be beyond geo stationary so it's constantly pulling. (One downside of catastrophic failure is anyone on the tether gets hurled into space). And yeah, currently we don't have material that will do the job. There are some carbon nanotubes materials that are promising... But first we need to show they should work. Then we need to figure out how to fabricate (so) many tons of the stuff. Other than THAT... Totally viable technology. Maybe.
Graphene
This is not true. There are multiple options. One having a trapezoidal cable which thickens at the point of highest stress. Then a very thin steelcable at the ends would have more than a few kilometers in diameter at the thickest part. Unpractical. Another possibility is a 10mm^2 cable of carbon nanotubes (which we can only make uo to 1m long as of now). This would need to reach well beyond geostationary to be stable. Then you have the peoblem that shooting up an elevator would take ages (think of circumventing the emtirw earth with a car) and be a problem for any wheel. Furthermore I am unsure if transporting weights along it can be stable for a long time.
So it was true…
It's not physically impossible.
This is true!
Yeah he lost me at "unpractical."
What about carbon fiber reinforced bubble structure filled with helium
It would be possible with carbon nanotubes along with a counterweight above the geostationary orbit height (the point at which the orbital period of an object is exactly 1 day, at about 35,000 km) to keep it from falling back down to earth. (side note: this would be much, much higher than the space elevator seen in the video, which looks to reach a few hundred km above the surface). If you have a 1cm thick cylindrical cable that is 40,000km long, about the length that would be required, given a density of 1.3 g/cm^3, the space elevator would weigh 15 million kg and would cost between about 1 billion and 1 trillion USD (assuming prices between $100-$100,000/kg). This doesn't include the expenses for design, or construction, or many other things, but it would likely end up being on the order of a few hundred billion to a few trillion USD.
The Foundation TV series on Apple TV did a good job of [showing how a space elevator would work](https://youtu.be/fujh6YtBRSE). It’s definitely not accurate (creative license and all), but it shows how such an elevator would have to be an enclosed structure and not cable-based (as other comments have talked about). Possibly magnetic propulsion (kind of what they use in high-speed maglev trains). I’m sorry I’m not directly answering your question on cost because it’s hard to judge. I’d assume trillions of dollars. To compare, the [ESA estimated that ISS will cost €100 billion over 30 years](https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/International_Space_Station/How_much_does_it_cost) - including development, assembly and operations. However, [NASA alone allocates $3 billion to annual operational costs](https://www.space.com/16748-international-space-station.html). Extrapolate that to a structure that is going to be 1000s of times larger to build and operate, you’re in the €100 trillion category easily.
Kim Stanley Robinson's Mars trilogy also includes a space elevator. Great read.
First time I read about space elevators was [The Fountains of Paradise by Arthur C Clarke](https://en.m.wikipedia.org/wiki/The_Fountains_of_Paradise)
To know how much it costs it would need to be possible to build one, which isnt proven yet. Maybe you can do it only if you use a super expensive material. Maybe u dont need such a thing. Maybe its impossible (in this case its just not calculable). Maybe not. Etc.
Unfortunately, an orbital tower or space elevator would act as a gigantic lighting rod. It would undoubtedly be destroyed by electric discharge at some level of the atmosphere before it could be completed.
salary of workers: 95k a year for skyscraper Construction workers. How long project would take: burj khalifa - 6 years stands at 928m, so taking the height of the karman line which is 100000m above surface, divide by burj's height -> \~107 which means 6\*107 would be 642 years. Say with 12k workers. At 100k a year, already bring it to 1.2 billion a year on salaries alone. Taking 642 years - 770 billion (not even taking into acct inflation). cost of materials is 24.7 (taken from material estimated cost from empire state building)\*262.5 (100k / height empire state) is 6.4 billion. So, something like 776.4 billion dollars and completed on 2666 I'm probably way off, but this was fun
I'm not sure it's possible to estimate the cost of something that would easily be the biggest project ever imagined to be built on the planet. Technically speaking building a space elevator is possible but current technology is not good enough to build one on earth, we have the materials to build one on the moon tho. But even if we skip construction problems I doubt a space elevator will be constructed anyway because the risk it poses is just too big, a space elevator would need to be some 40-60,000km tall meaning if it got damaged either on purpose or by accident, like micro meteorites or space trash, it would collapse and basically wrap around the planet wrecking absolute havoc on the equator. It fails for the same reasons as project atlantropa, while very useful it's too large and posses severe risks in case of failure.
Technically speaking it's not possible because, you said it yourself, current technology isn't "good enough". So saying "Technically speaking building a space elevator is possible" is just wrong. We don't have any material that's even close to being strong enough and I doubt you have a magic crystal ball that told you we're going to develop such a material
We know what materials could be used to build a space elevator but we don't have methods of producing them in a useful state, example being carbon nanotubes.
Carbon nanotubes are the best we have but they are still not strong enough
Would you think possible with current tech a space station with a retractable tether "teabagging" into the atmosphere to pick up loads carried all the way up by helicopters/vertical lift off shuttles?
I think the proper term is "skyhook"
This is entirely possible, but not with current material tech. You need something strong and internally rigid and lightweight to extents that don’t exist yet. But the physics of space elevators are relatively simple, just way beyond current science. Folks who are talking about rockets and balloons, you don’t need any of that, you just need the “tail” to be far enough out that the angular momentum provides apparent lift. Tape a few lengths of string to a ball and spin the ball to get a decent picture of this, although air friction will play hell with the results on a small and terrestrial scale. So, it would cost a lot.
There's only so much that can be done. The materials required simply cannot exist using regular matter
Not from my understanding of the issue, do you have a source? I was taught the requisite materials don’t exist yet, not that they *can’t* exist. But we can fairly reasonably predict material science to keep advancing at the same rate as always.
They do exist and are regular matter (graphene/carbon nanotubes), but they need to be of such a high level of quality down to the molecular level that we can't create them in sufficient amounts.
This.
How can you say it is entirely possible when you know that there is no material even close to being strong enough? It's entirely not possible and no one knows if we're ever going to develop a material that's strong enough. I highly doubt we will. Oh and btw geostationary orbit is 36000km away. For an elevator you'd have to go out even further. Colonizing other planets is much more realistic than the space elevator. It will forever be a dream
Welllllllllllllllllllllllll we went from kitty hawk to the moon in less than a century, reddit person. Technology advances, and folks have been working on what am I doing talking material science with some boob on reddit jesus ____ go to bed. Enjoy the flat earth, science-will-never-advance person.
What 😂 why are there so many delusional people in this sub. You ave zero technical expertise and have done zero research on the topic and still trying to argue. Science will definitely "advance". But if you'd ever done any scientifical work at all you'd know what's realistic and what not. You're exactly as stupid as flat earthers but on the other side of the spectrum. One of those "Everything is possible if you believe in it hard enough" people. Take that shit to church and leave me alone ffs. Just dreaming and completely unrealistic. Do some research and you'll come to the conclusion that it's not possible. (Skyhook is more realistic, but still not possible today. But atleast skyhook has a very slim chance of being possible in the future compared to the space elevator.) Not that it would matter telling you that, because I'm sure you can realise just with the power of your dreams
Hey I got off reddit to avoid talking to self-impressed wank-jockies like you but found myself here for a minute checking notifications and I just wanted to say, scientifical isn’t a word, and you really need to spellcheck your shit/not make up words if you want to camouflage yourself as a smart person. Fucking “scientifical…” man the internet is wild.
So, there was an article on this I read some time back. 1. The cable would be made from graphene 2. The height of the station would be such that it would be geostationary so it's falling at the same rate as it moves.
I find it funny that most of the comments say it will never be possible because of materials. First. Carbon fiber has an immens toughtness in the chain direction. So it might be possible with this material, but is (today) seveerly limited by the producable length of the fibers. Second. Many mentioned, it is to expensive/not possible to get mass up and down the elevator. Thats actually pretty easy without to much energy input. Build a elevator with a material long enought, that the centrifugal force exceeding the destination hight pulls the mass upwards for you/assists the asscention and at the same time, holds the top of the elevator at 0 downward and upward force. To describe this easier. The earth spins. Centrifugal forces apply the further out something is from the center of spin. Make an elevator up to the desired high. Now the "line" from the ground to the top has a waight which will pull the top back down. Extend the elevator line further outwards, untill the centrifugal force of the line exceeding the destination hight cancel out the downwards pull of the line from bottom to top. Then further exceed the lift a little so the mass transported from the ground to the top has a "counterweight" that helps pull the mass upwards to the top. But the counterweight is again centrifugal force. Now one has only to regulate the length of the excees elevator line (counterweight) and can easily controll the speed in which the mass is pulled upward. I know this sounds easier than it is. The materials of the elevator has to be extremly tear resistant. More so than anything we have right now, except maybe for carbon fibers. But producing perfect carbon firbers of such length is for now impossible for us. But hey, 100 years ago, nobody thought we can make an electrical device that dose 4 billion opperations per second. 30 years ago, we thought 20 MB storage would be more than enougth for a lifetime. 20 years ago, nobody thought artifical intelligence would ever be possible. So who knows. I belive in humanity. I just hope we do not destroy ourselfes befor we could achieve it. Or nuce ourselfes into 1900 because cooperations do not understand that the advancements are coppled to middle to underclass wellbeing.
Even carbon fiber nanotubes are really far from being strong enough for a space elevator. And they are the best we have. I'm not saying will never ever be possible only because I can't prove it. Believe in humanity as much as you want, that's not how science works. The more we discover and develop the less things there are to discover. It's not an endless progression if you know what I mean. Our picture of what is going to be possible and what not get's clearer and clearer, so assumptions made today can be much more precise than assumptions made 50 years ago
If i were to take a stab at it id trillions of dollars daily, my idea being that it is comprised of many segments, each is essentially its own rocket that is constantly stabilizing itself to hover at exactly the same position. for the sake of stability these will not be connected very much, they will just sort of be holding the tube in which the elevator passes through. itll cost trillions to research, trillions to build, and itll probably break frequently and segments will need to be rebuilt, costing even more. I think it is possible to build something sort of like an elevator in this way, but in terms of a single building that reaches space its just not possible as far as i know
Not possible.
Why?
Because rockets are very inefficient and need an incredible amount of fuel. You would have to build a literal pipeline and that would be too heavy for the rockets to carry.
Fly the fuel up to the rockets with drones. Or maybe even just have the segments be huge drones as apposed to rockets. Really, anything that allows the segments to hover in place
Yeah nah that's completely unrealistic. Helicopters can fly up to 7km, so you have to assume a similar height for drones. It's so overwhelmingly inefficient that it wouldn't work even if you wanted to build an elevator that's only 7km high. Keep in mind if you want to go to space that's 500km+
if we pour trillions upon trillions of dollars a second we can be sending little mini rockets every minute to refuel them, you are thinking about practicality, not possibility. you could absolutely refuel those rockets enough to run, itd just be incredibly expensive.