arrives in space "oops wrong floor"

Real Engineering: **shows equations** Me (with very little physics knowledge): Ah, yes, OF COURSE!!

Hey man, I remember subscribing to you in early high school, you only had around 1,300 subs and I saw your “this is engineering” video i’m now halfway through college pursuing aerospace aviation. can definitely say this channel has solidified my career path. thanks homie

"The steel at its widest diameter would be wider then the known universe" well now that is a design challenge isn't it?

"The space elevator will be built about 50 years after everyone stops laughing." - Arthur C. Clarke

Short answer: We have the maths and the engineering parameters but significantly lack in the building material strength to weight ratio category.

Imagine taking the stairs when the elevators down! You'd be fit in no time!

Isaac Arthur has me convinced that if we master cheap carbon nanotubes, graphene and fusion power then anything is possible lol.

Guess someone has been learning 3D modelling, seeing those starting Mustard-like animation.....😁😁😁

In the early 1990s, Clarke was asked when the space elevator would become a reality. He answered, “Probably about 50 years after everybody quits laughing.”

I remembered one book I read about the space elevator that was "The Fountains of Paradise" (published in 1979) by Arthur C. Clarke. The original idea of the space elevator was from the deaf Russian scientist Konstantin Tsiolkovsky who was fascinated by the Eiffel Tower in Paris in 1895. 👍🤠👍

One of my favourite videos of all time! Even though I'm not particularly interested in space, and I prefer to look at more earthly problems

Me clicking on this video being 12: My dad: runs over seeing I “have interest” and teaching me EVERYTHING about engineering.

To quote Tom Hardy's character in Inception: No, it's perfectly possible. It's just bloody difficult.

From my point of view, beside the issues you said about manufacturing this elevator I think some landing platforms will be needed at every 10000 meters for maintenance.

This is why the foundation of Arthur C Clarke"s space elevator in The Fountains of Paradise was a new, miraculously strong and thin material, able to hold the weight of a man by a gossamer thread.

Normal people : I don't see why it's impossible KSP players : *Spending 40 hours Building the Space elevator just for gigs* Ace Combat players : *

I understand flat earthers now it’s much easier to say “no that wrong” instead of learning all that math. Props to all the research and knowledge which went into this video.

Material constraints represent a real challenge for engineering nowadays maybe with the advancement of space colonization we can discover new materials that can help make these ambitious projects possible

Fantastic video, I'd love to know how this compares to the physics of a Skyhook and whether similar limits apply to the materials.

I really enjoyed this more math heavy episode. Though I wish you'd also done the examples for the Moon and Mars as they have lower gravity given people have suggested them for eventual manned bases

Smoothest transition into an advertisement I've ever seen. It was almost seamless👍

Sky hooks are cooler, and all ready have everything we need to build them, no new material needed.

Thank you for the amazing video! Your videos have always been great, but it looks like they've made another jump to a higher level of quality. This one is just about perfect.

Anyone interested in more videos on this topic (but difficulty scale taken to multi-galaxy-collapsing levels) can look up Isaac Arthur's channel. (He actually has an entire series on space infrastructure that's specifically about getting people and material off earth.)

I wrote a paper on space elevator feasibility in order to graduate highschool. It was such a difficult topic for me to wrap my head around so seeing you use the same sources, equations and coming to the same conclusions as I did was extremely gratifying. Oh and the sources on this topic vary widely in quality to the point of extreme frustration on my part.

I keep hearing "Daybreak's Bell" by L'arc en Ciel and seeing three superpowers build three of these things for their own gain and prestige.

Just a small correction: the reason super tall buildings have a wide base and nonprismatic narrowing shape is not to reduce total gravity load, but to combat coherent vortex shedding -- where wind forces become amplified at a specific frequency. Primarily that, but also to reduce overturning moments via lengthening your moment arm. An additional factor is you have less surface area at the upper stories driving up base overturning wind moments. You could theoretically build a square super tall building in a vacuum without issue. You'd simply have more large columns.

Kerbal Space Program players at 3:14 - "AAAAH NOOOOO"

8:01 reads "denoted" as "donated" off the script lol

I'm glad you touched on the space debris aspect. We would definitely have to ensure there were no uncontrolled objects in orbits that could intersect with its path before it could be feasible. I think there are 90,000 objects currently being tracked, plus many more that are too small to track. This makes me skeptical that space elevators will be feasible any time soon. Also, if we can crack fully reusable rockets, the advantages of space elevators may be a lot less then the proponents would like us to believe.

Two points, 1) the taper ratio does not need to be accomplished with just one fat tether. It could be done in stages with multiple tethers. 2) he says the orbit cannot be elliptical but if it was and the lower end was not attached to the earth it would just bob up and down. If at perigee it dropped into the atmosphere you could attach your payload from a plane and let the elliptical orbit lift the payload without a need to climb the tether.

other less discussed issues on space elevators is variable amounts of drag along the due to variable weather and increasing altitude, and whether it can properly resist or transmit thermal heating from friction and electric magnetic effects which snapped a multi mile long tether experiment on a space shuttle mission, and what kind of impact if any such a megastructure could have on earth/solar interactions, and what kind of tidal loading are earth, moon, sun interactions going to put on it; and whether micro organisms carried by the rain would colonize and begin eating the yummy line at the bottom, and how the top could survive contact with natural or unmanned space debris. The benefit of most space craft is that you don't get sea barnacles trying to grow on them, and if they are in danger you can boost them to a different orbit. This one is anchored. Actively defending the structure from "the elements" could be cost prohibitive even if building it is not. I think people could build them somewhere, the earth system just doesn't seem to be the ideal planetary situation for that type of space infrastructure.

"703rd Floor, Women's Lingerie."

Great video! You covered this subject in an interesting, detailed, and understandable way. Even your coverage of Brilliant was well done and informative. It is very useful. Thanks!

11:00 and we shouldn't forget the chemistry. The material should be inert to corrosion or at least be shielded against the temperature ramps, humidity and other chemical corrosion.

So will the elevator music be Led Zeppelin’s “Stairway to Heaven”...?

"..at an astronomical scale.." don't you mean planetary scale?

love the videos, keep it up. I am always fascinated, entertained, and informed when watching these

Ide be interested in seeing what the Coriolis effect would do to the structure. I imagine wind resistance would be a thing because one end would be moving insanely fast and the bottom would be sitting still

Elevators are more llkely to appear on the moon and smaller moons without atmospheres, also the The tether needs to be non conductive and radiation resistant. Micheal Lane at Liftport has done a lot of work towards developing a Lunar Elevator. Vectran is a material to investigate.

As a long time Halo fan I've always found the concept of space elevators to be really interesting.

Excellent breakdown. If more people would take the time to look into things for themselves rather than simply accepting and passing on someone else's findings, lots of problems could be avoided. This is useful not only in engineering, but in the media as well. Too many people accept the claims presented by the media without any critical thinking involved.

A layman question: What about the velocity? ... If a mass is lifted up, it will 'drag' the cable/station. You need to 'accelerate' the mass horizontaly, from the 'ground-speed' to the speed of the station.

The good thing is that a space elevator only requires two control panel buttons; Lobby & Space Station.

7:55. How generous of T to kindly donate the stress value

Assuming the materials exist to creat this structure we will need to build several “strands” out to the counterweight so cargo can move up and down simultaneously. Transit time has to be taken into account also. Traveling thousands of miles will take time. Multiple strands will allow separate loads running at different speeds. Express for people to minimize time and more leisurely rates for cargo determined by most cost efficient power requirements.

First. We make multiple towers. Many. We put the motor the carries the cables up at the top of most. We use shorter cables. You go up one tower. Now you attach to cables on the other tower. We use mount everest as a starting point. So at the peak we build a huge thing that goes up from there and also sideways and we have many pillars connecting to the main beans that head horizontal from the peak of Everest in multiple directions.

So... "Not currently, but maybe in the future with new materials".

Orbital rings are where it's at. You can buld them just a few 100km up, meaning you can make the cables out of things like Kevlar, and they are much more versatile as they can actually launch and catch spaceships and send them out to the moon or even interplanetary.

As a physicist, hearing the words "centrifugal force" makes me cry. Newton would be quite upset. Apart from that, nice video and very interesting as always

It won't wrap around if it has the same angular velocity as the Earth. Also if you tether it from multiple points, you don't need it to be tethered at the equator. Also it won't be in orbit bc it won't be free falling. If anything, we'll have to reorient satellite orbits to avoid hitting the tether at a huge relative velocity. Isaac Arthur's channel goes over orbital elevators quite nicely.

I love how he explains things in a way that I can understand with my tiny, barely graduated high school brain. It also really drives my desire to pursue education and knowledge in higher mathematics, physics, and engineering. If only there was some sort of website he could recommend for stuff lile this!

When I saw the title I immediately think of Gundam 00 (Edit from the future: it also reminds me of Ace Combat 7 now because I just started playing AC7 as well as the PS2 trilogy)

I remember when i was smart enough to even begin to understand these equations. Now its nothing but a memory of a different me.

Love this channel. Great content and the engaging narration is a big bonus.

So what I saw in the anime; Gundam OO (Double O), the animators and designers were on to something when they made the orbital elevators in the anime? We just need better materials to make it work? Mind blown. And here I thought that the Japanese have a hard on for space elevators when they kept putting them in their animes...

"The ocean of stars in our galaxy is finally within our reach... The universe lies ahead of us, waiting to be discovered. And now, at last, we have a gateway to ascend to it. Over and over again."

I like how he just casually points out issues and mistakes in a scientific paper while doing research for a youtube video :D

Great video! In future videos on the subject, please consider reviewing the centennial challenge tether tests and the unit invented for this topic, the Yuri (30megayuri or bust!)

As a science-fiction writer (working on his first novel), I cannot say how happy I am to see my calculations confirmed. I didn't nearly go into as much detail, but for things like the altitude of the counterweight, etcetera... I'm happy to see I was correct. A very exciting new series, can't wait to see the rest.

Me, an AC7 and AC's series fan: *MMMMMMMMMM.*

The After Effects work in this video is incredible!

Build it on Everest and cable will be 8.89km shorter than at sea level. Add a big enough air balloon that can hold the cable up to 20km and the rest of the cable will have a lot less strength requirements.

gundam gn-000 wonderfully displayed the space elevator concept to me as a kid then later Isaac arthur elaborated on it i like the active support concept for space elevators.

Imagine the insane temperature differential along that tether, even more so in the day/night cycle

As an Ace Combat fan, I truly hope that we make one.

"Are space elevators possible?" "Cities skylines joined the chat"

Real Engineering: *Makes a video about space elevators* **President Harling wants to know your location**

3:14 as a Kerbal space program player, this just feels wrong.

Thanks for pulling this idea back down to Earth.

Our biggest hurdle to building a space elevator is our material science.

*sees Title* Me: "are we going Ace Combat 7 now?"

Please make a video on Sky Hooks as an alternative to Space Elevators.

One amazing way of applying this and other related knowledge I've found was the book "seven eves" by Neal Stephenson It's a realistic (or as close to as far as I understand it) scifi book where the earth's surface becomes uninhabitable for several hundreds of years Humanity gets about a two year head start, and immediately starts flinging stuff into space (It's set in a vague near future where the ISS is a lot bigger already) anyway, difficulties ensue, there's a timeskip in the book, and we see a society living in orbit around earth, slowly building its way back down. one of the ways these people get from the planets surface to space is this: you get a powered glider, fly into the higher atmosphere, where you reach the lower end of a spinning satelite. this satelite is essentially two pods on a REALY long string that spin in a geostationary orbit, just at the edge of the atmosphere. once your pod is pointing "up" (away from earth) you're in the lower bounds of space, and you can use a different means of getting into a "propper" orbit. Mind, this was all written from memory, so I might've missed a step or two, and I'm not a professional writer, so my descriptions aren't the greatest. but if this sort of stuff seems interesting I can really recommend it!

I think a space crane where a giant cable is lowered and then pulled back up is better idea.

6:03 woopsies. Forgot to add the reference number here. The link is the [3] reference in the description. Thank you to Brilliant for sponsoring this video. Beens slowly working my way through that course and refreshing my knowledge, in places I am evening learning new things! brilliant.org/realengineering/

6:00 There is no reference number appearing on the screen.

1. Fix potholes on highway 2. Replace waterline that keeps breaking 3. Build space elevator One thing at a time

Another problem not talked about is that any object climbing the cable has to either increase its angular momentum as it rises or take angular momentum from the cable/weight system. So propulsion is still required.

0:27 "lofty engineering challenge" - I see what you did there. :D

8:03 T is such a nice guy!

There are 2 things I never see discussed about space elevators. 1. If the electrical potential between the sky and the ground is 400,000 volts, would a space elevator "ground out" that charge and how would that mess with global weather? 2. If a space elevator is impractical on Earth, what about using one on Mars for future return trips? Thanks for another great video.

One challenge is the force on the cable. The mid-section of the cable has a strong lateral force on it. Satellites at lower orbits orbit much faster than the geostationary orbit. The cable will want to orbit faster than the top or bottom, leading to a curved profile for the cable, and more stress on it. There is no way around this issue. We will need stronger wire to make any progress.

Thank you so much for adding references to this; these videos are a great overview for research, so having sources is super useful.

3:04 In Kim Stanley Robinson's 'Mars' Series this exact thing happens and the results aren't pretty. Also interestingly that series features multiple space elevators and the ones on Mars are easier to make thanks to Mars' lower gravity.

Note that the path of the space elevator also needs to curve or lean spin-ward because as you go up you also need to add angular momentum. Going down you need to lose angular momentum. But the same curve should work if rates of climb and descent match.

There is one more problem with putting this in geostationary orbit: Above any populated place, there will be quite a bit of traffic in geostationary already, in the form of satellites for communication, TV etc. Might already be a little crowded up there already! (of course distances in orbit are much further apart than at the same point close to earth, but still, I doubt anyone would send anything up without figuring out where everything else up there is alerady!)

Are space elevators possible? Kurzgesagt intensifies

The height visualizations in this video are a bit misleading. The geostationary orbit you are talking about, is almost 100 times higher than the ISS (400 km). In the images here the orbit looks almost like LEO (low earth orbit). Geostationary orbit is almost at 3 times the diameter of the earth (12,700 km)

@ 4:15 - important perspective about how far up the station will need to be: 36,000 km above the surface of Earth is 35,592 km farther up than the ISS, and nearly 1/10th of the distance TO THE MOON, which is 380,000 km. Also, even travelling at 200 kph it would take roughly a week to travel the distance.

Would be great if you covered space hook concept next :D

Catastrophic failure of a space elevator was studied at my University. The results were so grim, it was said to be the worst idea ever conceived to climb to space.

Amazing video. We'd love to see you do a video on engineering aspects of "skyhook" as well that's just another alternative to space elevator.

Good luck with those flying asteroids and space junk

Simple grade-school physics question here: The conservation of angular momentum states that an orbiting object must gain energy to remain at the same angular speed if you lift it from one altitude (24 hr/revolution at 1670 km/hr at earth surface) to much higher altitude (24 hr/revolution at 11000 km/hr at geosynchronous orbit). Imagine spinning a weight at a known RPM at the end of a 10 meter string. Then allow another identical weight to slide down the string from your position in the center. The whole system slows down (in RPM) and you will have to add significant energy to speed it back up. This is why skaters slow down when they put their arms out... they didn't add energy to the spin, they just changed the orbit. BUT: Since every action has an equal and opposite reaction, this increase of energy in the space elevator climber will result in the "counterweight" losing the exact same amount of kinetic energy, thus slowing it down. I don't see how you will lift a load without slowing down your "counterweight", and once that slows down it is just a matter of time before it crashes into earth because it is now not a balanced system anymore. Changing the orbit of the "counterweight" or having a second counterweight on another longer tether might work the first time, but how do you get it back for the second lift without adding energy to the system? For every lift, you would need to lift a significant amount of fuel to speed the whole counterweight system back up. Not to mention the energy of just climbing the tether to begin with. It is likely that I am stupid, but there are hundreds of hours of videos on carbon nano tubes and other theoretical hype, but I've yet to see anyone tackle the simple physics of how this would actually work.

I remember reading a sci to book decades ago about space elevators. Fiction is always ahead of real time doing things.

Thank you for bothering to check the paper instead of just citing it. Damn thing should be retracted.

Possible explanation for that seemingly inexplicable steel strength figure, en.wikipedia.org/wiki/Wire_drawing The process isn't relevant for bars or other products, as they are too hard to draw, coupled with the fact that getting to the strongest strengths possible means numerous careful annealing treatments, so this is not really a cheap process to take to the extremes. Nobody quotes the numbers they can achieve as the strength of 'steel', because that is referring generally to structural steel sections, not extremely thin wires. These would also be quite hard, though not proportionate the way hardened steel's strength and hardness correlate. All that said, it's still not as good as the more modern options.

theoretically, yes. in practice though, it would require 3 things. 1. a super strong material that currently does not exist. 2. the ability to control the weather around the elevator. and 3. nothing in an orbit lower than geostationary.