This was incredible! Couldn't stop scrolling and reading. For a kid of a certain age and curiosity it'll blow their mind! I'm so grateful the creator made this, shame that his "buy me a coffee" isn't a simple PayPal or Apple Pay but you have to put in credit card or bank details!!
PayPal and Apple pay take a significant cut of the transaction. CC is a lot less and bank is mostly free of TX fees.
Most users don't know/don't care, so given the option, they will likely take it and funnel their donations to conglomerates.
How do you pay with PayPal if not putting in your credit card or bank details? link is a pretty well-known online wallet and much simpler to use than PayPal.
TIL it's estimated that over 48 tons of meteors hit the atmosphere every day.
Regarding actual space elevators though, while they're not sci-fi to the extent of something like FTL travel - ie. they're technically not physically impossible - they're still pretty firmly in the realm of sci-fi. We don't have anything close to a cable that could sustain its own weight, let alone that of whatever is being elevated. Plus, how do you stabilize the cable and lifter in the atmosphere?
A space elevator on the moon is much more feasible: less gravity, slow rotation, no atmosphere, less dangerous debris. But it's also much less useful.
Space elevator was the perfect application for carbon nanotubes according my professor few decades ago. I wish humanity could unite for such project and enter space exploration phase. But I feel it will stay sci-fi forever.
The problem with space elevator is not only the lack of material today, but also the fact that such elevator is an ultimate and very fragile weapons platform, you basically get stones up the well and then drop them on the enemy. Meaning that any authoritarian country would destroy it even before it is ever built. And sturdy enough space elevator after it's break at any high point would start falling down on the planes in a loop, eventually flattening everything in its path when higher portions reach supersonic speeds. So unfortunately there is low chance it will be built, unless we sort out stuff on the planet first.
> A space elevator on the moon is much more feasible: less gravity, slow rotation
The slow rotation is a minus, it means you've got to string the tether up to L1 instead of "just" up to geo/luna-stationary orbit. A lunar space elevator needs to be at least 56000 km long, more than 20000 km longer than the one to earth.
> But it's also much less useful.
Yeah, especially because all the things that make lunar space elevators a little more attainable also make lunar mass drivers a lot more attainable. Why ride in an elevator for a week if you also can just be fired from a cannon?
Almost all discussions around space elevators focus on the cable itself, how to manufacture and deploy it, and completely forget about the issues that would arise afterwards:
1) How do you attach the climber to the cable without affecting its structural integrity? By squeezing it really hard? A material that's optimized for longitudinal tension strength is probably not very tolerant of lateral compression.
2) How do you provide power to the climber? A regular electric cable can't support its own weight, so either you have to attach it to the climbing cable, or you have to make it from the same material.
3) Is it even worth it? The climber needs to cover a distance of ~36,000 km, so even at 200 km/h it takes 7.5 days from the bottom to geosynchronous orbit. How many climbers and what payload can the cable support at the same time? Refer to issue #1 regarding limits in speed and mass per climber.
The throughput in tonnes/day is absolutely abysmal in relation to the immense upfront infrastructure cost per elevator. Compare this to SpaceX's Starship, which is getting closer and closer to fully reusable 100 tonnes to orbit in minutes. Space elevators will stay science fiction forever, not because they're infeasible, but because they're useless.
#1 is one of the things they typically get wrong in stories.
Climbing the cable is a nightmare, especially as it gets thicker as you go up. Thus do not climb the cable! Rather, when the cable is built a whole bunch of anchors are built into it. You are not climbing the cable, you are climbing a track on the side of the cable. The cable's job is to support the track plus any load on it.
Well if it's contingent to having massive amounts of unobtainium and subject to unsolvable engineering reality check conundrums then it's just as unlikely as an Alcubierre drive which "only" needs exotic matter that allows negative energy.
While a space elevator doesn't contradict any fundamental limits of physics, that doesn't mean it's actually possible to build one. There is no reason to be certain that it's actually possible to create a material that has the required characteristics in terms of tensile strength to support it's own weight, plus the weight of the elevator, plus the weight of all the additional cabling. It also has to endure the huge temperature differences that it will experience along its length and from day to night and from season to season.
This is especially true considering that you don't need something that barely holds - you need something that you know will hold up to many times more weight than it needs to, so that it can be safe: the potential energy such a thing would store would be enough to dig into hundreds of meters of rock all around the world, if it ever crashed. So, you have to ensure there is no realistic chance of it ever crashing. It also has to be highly non-fragile in other ways, so that a madman with a bomb or a freak collision with an airplane or a meteor (especially likely in the thin upper layers of the atmosphere) won't bring it all down.
This combination of properties may well be completely impossible to actually achieve in a material. Even if there is no obvious basic law of physics that it would break, that doesn't mean that it wouldn't break other, harder to touch, derived laws.
thing is we do have materials strong enough, because as it turns out the issue with strength is in flaws between indivual molecules in any given material, not so much the type of material, and very small amples with perfect molecular bonds are plenty strong, but getting consistent perfect molecular bonds is the challenge,
and if this can be done, other technologys ,such as vacume ballons
will be possible, such as flying citys to go with the space rlevators
Thanks! I found a funny hack: DVD logos generate stimulation per bounce, so ... let them fly for a few seconds, then resize window to small size and back. Lot of bounces as the logos get caught by the moving edge :).
I did the same. I eyed it suspiciously and thought to myself, "This site is really well designed. Do you think if I..." and it did switch! The obvious interaction was implemented! Rare these days.
I just looked at it in the dev console in a chrome based browser and I think it is already pretty optimized. It runs very smooth on my device (Thinkpad T480).
If anything, "evolution" filters out disadvantages (eg: can't survive because your neck's too short and that pesky giraffe is eating all the leaves you could reach).
Giant Space Bola is much more attractive. It is a 10000 km string with capsules at both ends. It rotates in sync with earth so that the speed at meeting point is the same. You just hop in and end up in space without much effort. Because it is freely floating you can move it around to avoid meteor impacts and other such shit.
I loved the visuals but space elevators are far more science-fantasy than hard science-fiction. We should move on to sci-fi tech that has more realistic applications.
It is appreciated that you can change the temperature unit by clicking on it, and how surprisingly cold and changeable the temperature is as you travel up through the atomic sphere (down to -84C, -119F).
What's really interesting is that a space elevator goes to Geostationary orbit by necessity. Getting to 100km vertically doesn't save as much as you might think when it comes to getting into orbit.
To get into a very low earth orbit from an equatorial launch pad at sea level you need about 9.2km/s of Delta-V
To get there from a 100km tall tower, you need about 8km/s of delta-V - about 85%.
Think about how much scrolling there was to get to 100km.
To get to the ISS you'd need to scroll 4 times further. Starlink and Hubble are another 100km beyond that.
You start having radiation problems if you spend too much time above 600km.
Aside from Apollo, the highest a human has been is about 1400km - 14 times more scrolling than this page.
To get to GEO would require scrolling over 25 times further than even that.
125 comments
[ 5.3 ms ] story [ 74.5 ms ] thread"That's not flying, that's just... falling with style!"
Accelerate upwards fast enough, you can so to speak fall upwards for a short while before you fall back down again...
Learned that sprites can be 50km long!!
Regarding actual space elevators though, while they're not sci-fi to the extent of something like FTL travel - ie. they're technically not physically impossible - they're still pretty firmly in the realm of sci-fi. We don't have anything close to a cable that could sustain its own weight, let alone that of whatever is being elevated. Plus, how do you stabilize the cable and lifter in the atmosphere?
A space elevator on the moon is much more feasible: less gravity, slow rotation, no atmosphere, less dangerous debris. But it's also much less useful.
The slow rotation is a minus, it means you've got to string the tether up to L1 instead of "just" up to geo/luna-stationary orbit. A lunar space elevator needs to be at least 56000 km long, more than 20000 km longer than the one to earth.
> But it's also much less useful.
Yeah, especially because all the things that make lunar space elevators a little more attainable also make lunar mass drivers a lot more attainable. Why ride in an elevator for a week if you also can just be fired from a cannon?
1) How do you attach the climber to the cable without affecting its structural integrity? By squeezing it really hard? A material that's optimized for longitudinal tension strength is probably not very tolerant of lateral compression.
2) How do you provide power to the climber? A regular electric cable can't support its own weight, so either you have to attach it to the climbing cable, or you have to make it from the same material.
3) Is it even worth it? The climber needs to cover a distance of ~36,000 km, so even at 200 km/h it takes 7.5 days from the bottom to geosynchronous orbit. How many climbers and what payload can the cable support at the same time? Refer to issue #1 regarding limits in speed and mass per climber.
The throughput in tonnes/day is absolutely abysmal in relation to the immense upfront infrastructure cost per elevator. Compare this to SpaceX's Starship, which is getting closer and closer to fully reusable 100 tonnes to orbit in minutes. Space elevators will stay science fiction forever, not because they're infeasible, but because they're useless.
Climbing the cable is a nightmare, especially as it gets thicker as you go up. Thus do not climb the cable! Rather, when the cable is built a whole bunch of anchors are built into it. You are not climbing the cable, you are climbing a track on the side of the cable. The cable's job is to support the track plus any load on it.
This is especially true considering that you don't need something that barely holds - you need something that you know will hold up to many times more weight than it needs to, so that it can be safe: the potential energy such a thing would store would be enough to dig into hundreds of meters of rock all around the world, if it ever crashed. So, you have to ensure there is no realistic chance of it ever crashing. It also has to be highly non-fragile in other ways, so that a madman with a bomb or a freak collision with an airplane or a meteor (especially likely in the thin upper layers of the atmosphere) won't bring it all down.
This combination of properties may well be completely impossible to actually achieve in a material. Even if there is no obvious basic law of physics that it would break, that doesn't mean that it wouldn't break other, harder to touch, derived laws.
On Earth.
Zylon or M5 [1] could build an elevator on Mars. Kevlar on the Moon.
To drive this home, it’s estimated we could build a lunar space elevator for less than what Bechtel fleeced NASA for a mobile SLS launcher [2][3].
[1] https://en.wikipedia.org/wiki/M5_fiber
[2] https://opsjournal.org/DocumentLibrary/Uploads/The_Lunar_Spa...
[3] https://oig.nasa.gov/wp-content/uploads/2024/02/IG-22-012.pd...
Re playing this gem https://neal.fun/stimulation-clicker/
What evolutionary advantage, I wonder, is there to Ruppell's griffon vulture flying at 11400 meters?
edit: units
If anything, "evolution" filters out disadvantages (eg: can't survive because your neck's too short and that pesky giraffe is eating all the leaves you could reach).
Evolution kills what doesn't work.
[1] https://en.wikipedia.org/wiki/List_of_birds_by_flight_height...
[2] https://web.archive.org/web/20131011012320/http://blogs.bu.e...
* Jeez, Everest is tall
* They got a plane to 17km in 1938!
* There was a paper airplane flight at 35km
Awesome site!
To get into a very low earth orbit from an equatorial launch pad at sea level you need about 9.2km/s of Delta-V
To get there from a 100km tall tower, you need about 8km/s of delta-V - about 85%.
Think about how much scrolling there was to get to 100km.
To get to the ISS you'd need to scroll 4 times further. Starlink and Hubble are another 100km beyond that.
You start having radiation problems if you spend too much time above 600km.
Aside from Apollo, the highest a human has been is about 1400km - 14 times more scrolling than this page.
To get to GEO would require scrolling over 25 times further than even that.
https://neal.fun/deep-sea/