To everyone saying launching to orbit is impossible, I have two words: Orion Drive
Early versions of the vehicle were designed for ground launch, but later versions were intended for use only in space.
I don’t think a ground launch Orion Drive would work without some crazy material science and infrastructure. Like a “flame trench” that can withstand a nuclear blast and a craft that doesn’t rip itself to shred just from the shockwave alone.
so it’s possible, once
So… Dark Forest strike? paint them?
According to Wikipedia this planet has an estimated surface gravity of 12.43 m/s2 with a margin of error of about 2 m/s2. That’s only up to 50% higher than Earth’s 9.8 m/s^2 (on the high end of the error margin) so it probably would be possible to get into orbit.
That said we don’t actually know much about it for sure. We don’t know if it’s a terrestrial planet for example. It could be composed mostly of gases and liquids like Neptune.
I assume it’s not just about the gravity, but also the much larger radius of the planet would mean much larger distance from the surface, and thus much more fuel needed.
You’re sort of right. The change in distance from the surface is insignificant, but a spacecraft orbiting a bigger planet has to travel further with each orbit so its speed must be faster to avoid falling out of orbit, even if the gravitational acceleration at its orbital height is the same.
That’s not how…what???
F = G * (m1 * m2) / r^2
Escape velocity does scale with (square root of) radius so its not a dumb thought.
And I’m not a rocket surgeon but I could imagine earth rockets might be operating near some physical limits that make a 50% increase (or whatever) infeasible.
Wikipedia says
energy = GMm/r.if
g=GM/r²thenenergy = mgr, proportional to r given g is constant.apologies
My previous comment was wrong, I derivated while integrating.
I stated an assumption and was contributing to the conversation. Even if that assumption is incorrect, there’s no need to be a dick about it.
It seems like a larger atmosphere would result in a longer duration exposed to atmospheric drag, thus requiring more fuel to overcome it.
That’s, uh, not really how that works. A taller atmosphere would mean you have to go through more of it, but unless it’s not a terrestrial then the atmosphere won’t be that much taller.
If it is a non-terrestrial planet, it’s unlikely anyone would be building rockets on there to begin with.
If it has a higher gravity would the atmosphere technically be lower since it will squish up closer to the planet?
It would actually be impossible for them to get to orbit using chemical rocketry, like we use. They could theoretically do it with nukes.
(Not a rocket scientist or mathematician, but I spent 100s of hours playing KSP RP-1)
Just doing some estimates using data from the wikipedia page:
The dV (delta-V) needed to get into low Earth orbit is around 9.4km/s.
The dV for K2-18b might be around 19km/s, more than double that of Earth’s.It’s practically impossible I think, you would need such a massive launch vehicle. For double the dV, you would need exponentially more fuel assuming current rocketry tech (fuel+oxidizer tanks and engines). There wouldn’t be any single-stage or two-stage rockets that could do this. With a 3 or 4 stage rocket maybe? But you would be sending nearly 100% fuel off the launchpad with virtually zero payload.
I tried to factor in:
spoiler
- Atmospheric drag - K2-18b’s atmosphere is quite dense with a huge radius:
The density of K2-18b is about 2.67+0.52/−0.47 g/cm3—intermediate between that of Earth and Neptune—implying that the planet has a hydrogen-rich envelope. […] Atmosphere makes up at most 6.2% of the planet’s mass
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Since the atmosphere is so thick and takes up a lot of mass, I’ve picked 500km as the low orbit altitude (comparing to Earth’s ~100km Karman line, it makes you appreciate how thin our atmosphere is ).
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Rotational assist - I’m assuming it’s tidally locked since it orbits so closely to its star (33 day years), and so you wouldn’t get the assist from rotation like you do on Earth:
The planet is most likely tidally locked to the star, although considering its orbital eccentricity, a spin-orbit resonance like Mercury is also possible.
Build a large enough magnetic rail launcher and you could save shit tons of fuel. Get a ship doing 2000 mph before it leaves the ground and needs its rockets and you’ll have a pretty good head start.
Could even take a scramjet to the upper layers of the atmosphere before kicking in the chemical propulsion
I mean, that’s kinda still just adding on weight and another “stage” to the rocket. A scram jet hauling a rocket ship will use tons of fuel.
I thought scramjets were supposed to be really fuel-efficient? Just launch them with your gauss cannon idea so that they don’t need much fuel to get up to speed.
Maybe you’re right about the weight though. I’m not an engineer.
They’re efficient for what they are but think of it more like a gas pickup truck getting 30 mpg would be considered very efficient. But that would be terrible for a compact car.
Also, scram jets only get efficient once they’re going fast enough.
Yeah that’s why you do multi-stage like conventional jet -> ramjet -> scramjet
But again, yeah if it needs to carry a rocket then it might be unfeasible. We could try your gauss cannon idea, that sounds fun. Like a maglev train, but shaped like those rides from roller coaster tycoon where you could launch people to their deaths. Except instead of crashing, the rocket kicks on mid-flight. It could work.
tidally locked
Wouldn’t that be a non starter for life? One side would be perpetually baked and the other would be frozen.
I guess there could be a planetary Goldilocks Zone in the dusk area
I figured that area would be full of extremely violent megastorms due to the heat differential.
Oh interesting that is a good point
Kerbal Space Program is such an amazing game that secretly teaches you physics.
I’m stealing this
game that secretly teaches you physics.
those are the best!
Check out the “tyranny of the rocket equation”.
Or ask Randall Munroe How many model rocket engines would it take to launch a real rocket into space?
With a denser atmosphere, wouldn’t that mean that you could get more lift from a traditional aerofoil than on earth? And if so, wouldn’t that technically make it easier to start from a high enough altitude that at least some of the gravity is mitigated?
Let’s say you do the same on Earth. If you fly to the top of the atmosphere you are 100 km above the ground. That’s a 1/60 of the distance to the center of the Earth. You don’t have to fight air resistance but gravity is almost the same, if I’m not wrong, less than 1% of difference.
Yeah I realized that right after I made that comment. If the gravity is strong enough to hold a gas on the planet, it’ll definitely have a prominent effect on something denser like a solid.
That’s what i was thinking - the dense atmosphere might even allow for platforms which are permanently suspended in the air like an inverse submarine, offsetting a large amount of needed fuel for a space launch
What about something like nuclear pulse propulsion, or some kind of massive spin launch?
If it’s tidally locked, no spin assist.
Likely tidally locked
Missed that part but that doesn’t preclude what I was saying, just requires “more” of it
Nuclear propulsion, like Project Orion, would probably make it more likely they’d manage to get out of orbit. No idea on the math here, tho
https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)
yeah there’s also antimatter drives which give an even greater effective exhaust velocity (which is the speed of light). the highest possible achievable.
none have been built, so far
You don’t have to launch from the ground, there are many things that can be done to allow them to reach orbit. It’ll be an enormously bigger undertaking but the physics doesn’t make it impossible. No reason to think of it in terms of our current situation either, and we are behind our current level of possibly when it comes to rocket science, due to * waves at everything else *
Or Uranus.
Or your mother’s.
I’ve been wondering what a hypothetical perfect habitable planet for spacefaring would look like. Could you have one where a plane line the SR-71 Blackbird or an even less capable aircraft could simply “fly” into orbit? Or what about something Earth-like but with a flat plateau at 15,000 m where you could launch rockets from?
I think Mars, assuming you terraform it, would be pretty close to that on both counts. Space planes might still be difficult, but the delta V is much lower and Olympus Mons would pretty much sit above the atmosphere.
Holy shit, I hadn’t considered that you could use Olympus Mons as a launch site cause it sticks so high up.
The best part about it is that it’s an extremely gradual slope completely unlike the mountain ranges on Earth, so you could haul stuff up there on trucks or trains easily.
The problem is you can’t have mountains like that on tectonically active planets (a mountain that big on earth would sink into the mantle), which is kind of a prequisite for a long-term magnetosphere so its unfortunately not something a species could likely ever have except as a result of terraforming a world like mars and setting up some kind of artificial magnetosphere.
If that’s true, how did Olympus mons get there in the first place? I thought it was a volcano.
Mars was geologically active but its core cooled.
Is there a lower density limit for having a magnetosphere though? A habitable planet with 1.5x earth radius and the same mass would be much easier to get off of.
I guess that could work? Earth is actually the densest planet in the solar system so our baseline mass > size ratio might actually be a bit abnormal.
Classic planes require an atmosphere to generate lift. There’s an outer limit where that would be a viable mechanism, and on Earth it’s still far below LEO. Still too deep in the gravity well for ion thrusters to be viable. It requires chemical rocket fuels to bridge that gap.
Maybe someday fusion propulsion will break that limitations, but for now the best you can do is reduce the amount of fuel needed by flying to the upper atmosphere and reaching hypersonic speeds before kicking into rocket fuel propulsion.
Then after orbital injection, switching to ion thrusters to move around, and solar sails for exiting orbit into interplanetary/lunar routes.
Orbital speeds would be very hard to reach compared to low Earth orbits. Also a much deeper gravity well to escape for travel.
It’s probably still a lot harder though. You’re not just heavier, but also slower which means you’ll spend more time fighting gravity. And all the extra fuel you bring for that makes the rocket heavier which means you need even more fuel to launch the fuel. Higher surface gravity likely means a thicker atmosphere too which is a big issue and a more massive body also has a faster orbital velocity. Although in this case the larger diameter might counteract that a bit because higher orbits have slower velocities.
My point is that this would probably still be a lot harder than just building a 50% bigger rocket. If you’ve ever tried launching from Eve in Kerbal Space Program you know the pain. Although in that case you also have to fly the entire rocket there first which is its own challenge.
you’ll spend more time fighting gravity
Aw man. This is already a significant portion of my day.
I assume the amount of energy required for ‘only’ 50% more is massive.
Also i wonder since the diameter is larger, is this effectively like putting everything in a higher orbit which is also more difficult then if it was just twice as dense.
That really depends on the atmosphere. The lower the orbit the easier, but if you have too much drag from the atmosphere, you ain’t staying on that orbit easily
Apparently with 50% higher gravity it would be pretty much impossible with chemical rockets, but with the median of the estimate (so about 12.43 m/s2) it would be possible, you’d just need an incredibly large rocket, or non-chemical propulsion (e.g. nuclear).
A space program on that planet would definitely advance much slower than on Earth.
How well funded have our space programs been? Maybe they aren’t diverting massive portions of their resources to war and can actually focus on space.
They were well funded back when their real goal was to develop ICBMs capable of delivering nukes.
I get what you are saying, but the Saturn V was never intended to be an ICBM. Depending on what numbers you look at too, they weren’t actually that well funded. Some of the largest estimates that I’ve seen place NASA’s inflation adjusted budget between 1960 and 1973 at just under $600 billion. Or roughly half of what we’re spending in one year on the military currently.
To put it another way, at its absolute peak budget NASA received roughly 4.6% of the current military budget.
Iirc near that +50% level you end up needing a saturn 5 to launch sputnik, so its more expensive to the degree that it might just be deamed unfeasable, at least at the technology level humans started launching rockets at.
Much slower as in hundreds or thousands of years, so practically no difference at all.
We make a mistake by assuming that life forms would likely be at the same scale as us. Larger planets would likely develop life forms appropriate for those planets instead of appropriate for ours.
Uh… being smaller or larger does not really change the laws of physics… if the gravity is too high, no fuel has enough energy density to escape the gravity of the celestial body.
If you need 150kg of fuel to get 100kg worth of matter to escape velocity it does not matter how much fuel you have. It will not ever be enough to leave.
I love how Earthlings assume that all of the variables on other planets would be exactly the same as they are on Earth, leading them to believe they have any idea about what other species might be dealing with on other planets.
It’s cute.
You do know that they couldn’t even estimate the functionality of the heat shield of the spacecraft that just splashed down on our own planet? That they had to literally increase the angle of entry because they couldn’t accurately predict the behavior of a craft on a planet that they’ve been studying for all of recorded time?
Are the laws of physics actually a thing? Clearly. But here’s the thing: The kinds of organisms that might exist on such an object could be absolutely massive compared to us. And for us to assume that we would have an understanding of the laws of physics that would be anywhere near as great as animals that might have brains exponentially larger than ours? And hell, the energy that might be available in such environments? We don’t know what’s in space around these objects, or whether there are any kinds of characteristics which would make unconventional (to us) means feasible to get off of the planet.
For all we know, they could be scientifically a billion years ahead of us and might be able to manipulate time or matter in ways we couldn’t conceive. It hasn’t even been 100 years since humanity learned to harness nuclear power.
No, there are too many variables. Life on such planets could evolve in countless different ways, and the different characteristics of the environment, and the resources on and around the planet provide too many options for us to be wrong.
And before you respond that I am arguing against science, no, it’s actually your opinion that is arguing against science. History is filled with organisms finding unusual solutions for problems that were long deemed impossible to solve. And when people said “Well, I don’t think we have enough knowledge to make such a firm claim,” history is also full of people like you who insisted that there was no way. And history is full of people who walked into the room, picked up the rules as they wrre known to that point, and basically flipped over the game board.
You are literally the person arguing that a scientific process is impossible given environmental variables because they don’t match the laws of physics.
But you don’t understand that you are arguing not for the infallibility of those laws, but for the infallibility of our understanding:
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of the laws as we understand them
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of the chemical makeup and geography and resources of the planet
And all of that is not even to mention that the estimates of whether the planet itself was capable of supporting life have literally changed relatively recently because humanity developed a better understanding of science.
If I had a nickel for every time someone proudly claimed something to be impossible because it hadn’t scientifically been done yet I would be richer than Elon Musk.
Unlikely? Well, look. I’m not willing to make statements about humans’ accuracy when studying objects that far away. I will acknowledge that it’s not something that would be easy for us to accomplish given our current knowledge, but my humility can acknowledge that that seems to say more about US on this planet than it says about any kind of organism that may have developed on such a planet.
You’re treating scientific uncertainty as if it means “anything is possible.” It doesn’t.
We don’t assume variables on other planets match Earth. Astrobiology, planetary science, and exoplanet studies are built on the opposite assumption: that most planets don’t resemble Earth. When scientists estimate what life or civilizations could be like elsewhere, they work from measurable constraints (gravity, density, stellar flux, atmospheric composition), not wishful thinking. For example, we know that: A planet with 3× Earth’s gravity constrains organism size, structural strength, locomotion, and escape velocity. A planet with a dense hydrogen atmosphere changes chemistry and energy availability. A star’s light spectrum dictates photosynthetic possibilities. These aren’t guesses. They follow from basic physics and chemistry, which apply everywhere.
“They misestimated a heat shield” ≠ “we don’t understand planetary physics.” Engineering uncertainty in a single atmospheric re-entry doesn’t invalidate the underlying physics. Weather variation, material tolerance margins, and modeling limits don’t erase Newtonian mechanics or thermodynamics. If your argument were valid, airplanes would disprove gravity because turbulence is hard to predict. Scientific uncertainty does not mean lawlessness.
An organism the size of a mountain on a 10g world can’t simply evolve because “maybe their brains are bigger.” Biology cannot override: stress limits of matter metabolic scaling laws biomechanics gravity energy density limits An advanced species might innovate, but it doesn’t get to ignore basic constraints. A billion-year-old civilization would know more than we do, but they still can’t accelerate to escape velocity without energy, or support infinite mass with finite-strength materials. Knowledge does not nullify physics.
For all we know, they could be scientifically a billion years ahead of us and might be able to manipulate time or matter in ways we couldn’t conceive
This is pretty much just “We can’t rule out magic, therefore you’re wrong. Science can only operate on what’s known to be possible or what follows from tested theories. Speculating about physics-breaking abilities isn’t meaningful without evidence; it’s equivalent to saying “you can’t disprove dragons.”
When scientists say “a civilization on a super-Earth would struggle to reach orbit,” they base it on: the planet’s mass and radius → calculates escape velocity atmospheric density gravitational load on structures realistic energy sources We don’t need to know the exact geology to know that a planet of a given mass requires a minimum amount of energy to launch mass into space. That’s just conservation of energy.
Saying “we don’t know everything” is true. Saying “therefore any extreme scenario is viable” is not.
You’re treating scientific uncertainty as if it means “anything is possible.” It doesn’t.
Except I’m not.
I am treating things as if we are a species who barely has enough knowledge to send a small group of individuals off of the planet, and I am stating that while humanity seems to have a fairly okay ability to do that(and barely get to the next rock over), we probably shouldn’t be speaking with the confidence as if we wrote our masters thesis on interstellar travel. The moment humans stop having tons of massive scientific discoveries about space travel every year, that’s the point that we might have a good argument that it’s impossible for someone to escape a particular planet.
At this point, we can’t even confidently say that we know what that planet is like. Hell, up until recently, they believed that planet couldn’t even support life.
I am not questioning the laws of physics.
I am questioning that humans’ understanding of them is complete.
But you go on with your bad self, with your complete assurance that nothing will ever get off of that planet. The good news is that both of us will be dead before anyone even gets to know that it’s been tried.
You can question whether we know everything, that’s always fair. but saying “maybe something will escape a high-gravity planet because we don’t know everything” is like saying “Maybe we’ll find out 2+2 isn’t always 4 because math isn’t complete.” Possible? In a philosophical sense, yes. Useful? Not really.
Most “revolutionary” discoveries refine our understanding, not overturn the foundation. Relativity didn’t make Newtonian mechanics wrong. It expanded the domain. Quantum mechanics didn’t nullify classical physics. It explained small scales. Dark matter didn’t erase gravity. It suggests additional components.
When you argue, “We’re still making discoveries, therefore our predictions about what is possible are worthless,” you’re ignoring that the discoveries rarely contradict established, experimentally validated constraints.
You aren’t offering any reason to believe our current models are wrong, only that they could be wrong because science is incomplete. By that logic, any claim can be doubted indefinitely, and no amount of evidence ever matters.
But i truly like your child like enthusiasm for space. You throw intresting ideas around, but so far they have been only wishfull thinking. Difference between science, fantasy and religion is, that when something new is proven in science, people accept it, but it needs proof first.
In fantasy people throw crazy ideas and have fun, knowing they are not real.
Religion is when you have “faith” that something is true.
You are living in somewhere between fantasy and religion with your ideas. There is nothing wrong with it, but it makes discussions meaninless, because while i try to argue based on science you dont have any limitations and can just say. “We dont know, maybe they can manipulate time”. Its really convinient isint it.
Sure thing, Lord Kelvin.
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Damn. As if the atmosphere wasn’t enough of a hurdle already, they gots dumpys too
Most of the life we see on Earth isn’t even our size!
Life on earth scales from microscopic bacteria all the way up funguses that have an underground network covering thousands of acres.
The chances of us finding life on another planet is pretty slim, the chance of that life looking like us is astronomically miniscule.
Also, of all the millions of species that have evolved on Earth, only one has developed civilisation. We’re an anomaly, not an inevitability. Other planets could be teeming with life, but it’s happy to just chill in the forest/ocean/wherever.
That’s just blatantly incorrect.
Humanity believes that it has the ability to estimate the intelligence of other animals.
And the way that it does so is always by measuring how well the other species imitate human behaviors.
It doesn’t take into account whether those other animals care to imitate human behavior or whether they know they’re imitating human behavior or whether they want to imitate human behavior. And it most certainly doesn’t understand how well those other animals’ intelligence applies within their own niches. You can’t test animals’ intelligence by testing how closely they behave to human beings when operating mimicking human niches and human goals.
Speaking as someone who’s autistic, I’ve done the research on that. In autistic people, there seem to be a higher number of certain specific neanderthal genes. I’m also very gifted, and work in STEM.
Neurotypical human beings are BLOODY TERRIBLE at recognizing any type of intelligence that is different than neurotypical human beings. It is ASTOUNDING how bad they are at it.
Neurotypical people can’t even recognize the intelligence of autistic people. And good luck determining our goals. Other people think I am stupid when they first interact with me, but that couldn’t be farther from the truth. I’ll just say that revealing too much here would reveal my identity, and I’m not going to do that, but I have a list of accomplishments that I literally couldn’t imagine most neurotypical people accomplishing, and I know many other autistic people who are very intelligent. Does this discount neurotypical intelligence? No, not in the least, and it’s not intended to. But it does demonstrate that Fermi’s Law could be nothing more than humanity’s inability to identify other forms of intelligence. And hell, whether you even consider autistic people to be a different kind of intelligence, that’s not even referencing animals.
What neurotypical humanity HAS developed is not the only civilization, but the only widespread manipulation of the environment in ways that significantly distorted the environment in such a way that their presence was undeniable long after an absence. That’s not the same thing.
You underestimate the motivation of sentient species that just want to get away from other members of its species.
Getting to orbit? I don’t know if they can even stand up 😆
What does not kill them makes them stronger? 😎
John Carter of Mars? That you?
Already a struggle at 1g sometimes
You call Kepler I call it heaven, because if you think of it heaven is either fictional or a real existing place and I chose that planet as my impossible to reach place.
Ask your nearest local Mormon about Kolob.
Idk any Mormon but I had to Google it:
“Kolob is described in the Book of Abraham as the celestial body nearest unto the throne of God in LDS theology. In contrast, K2-18b is an exoplanet located 124 light-years away, known for its potential to host water and possibly life.”
Honestly didn’t know that religious people actually believe that heaven is a physical planet, always thought that it’s something spiritual, but good to know thanks for the enlightenment -
Imagine all the room for activities! (Trench warfare)
If the planet is massive enough, getting to orbit becomes a real challenge because fuel consumption scales roughly exponentially with the mass of a planet (delta-v formula, rocket equation).
This leads to an almost sharp cut-off for the maximum mass that a planet can have so that a rocket which utilizes chemical fuel (e.g. methane+oxygen) can still reach orbit successfully. This maximum mass is roughly 10^26 kg.
For reference: Earth’s mass is around 6*10^24 kg.
While other propulsion types exist, such as nuclear + ion drive, these propulsion types are significantly more complicated.
Interestingly, if a planet is too small, it cannot hold an atmosphere. There is a surprisingly sharp cut-off minimum mass for this as well, at roughly 10^21 kg.
I propose going to the south pole and just letting go??
I did not know that. It’s because it interferes with gravity? I’m dumb sorry
Not enough gravity, the atmosphere will drift away from the planet with the help of solar winds etc. Too much gravity, and the ammount of fuel you need to leave the plannet weighs more than the rocket the fuel is being used to lift can carry.
Even in our current ships, most of the fuel used to leave orbit is really used to carry the other fuel you need later.
That’s interesting! Thank you!!
We really are in the Goldilocks Zone, aren’t we?
Well, yes. In the middle of the goldilocks zone that is based on the environment we are adapted to is where you would expect to find us :p
Anthropic principle ftw
Haha fair point.
Only if there are not sentient life forms on that planet capable of getting off it
If anything, it’d be a bias towards spaceplane designs over straight up rockets. As long as the atmospheric density relative to the gravity supports it, offloading some of the acceleration to high atmospheric flight using ram/scramjets can massively reduce the launch vehicle mass (don’t need to carry oxidisers for the flight stage).
That being said, it also would be a bias against high orbits and space exploration in general; safe re-entry is tricky enough on earth.
I suspect that atmosphere composition makes different options more or less viable.
The difficulty/cost getting to orbit probably also would influence where a space elevator lands in terms of developmental priority.
What if, and hear me out… Giant trebuchet?
Or it’s likely a mini-Neptune type planet with more atmosphere than ground and therefore likely won’t have complex life at all. Or complex life able to try and do that.
They’ve just got to dig a hole down through the core of the planet and then drop craft down the hole to “slingshot” them into orbit.
I love slingshots that pull from all sides at once.
I’d sling that shot
A while back I read an article that stated earth was about as high G as you could get and still be able to get to orbit with chemical rockets (barring huge leaps in tech). I could be remembering that badly though, so take it with a grain of salt
Jokes on us: Because of the gravity issue, alien life on such planets jumps right to stargate technology.
“They spent almost a thousand years fooling around with rockets!”
Waddayamean a « ro-ket »? You guyas don’t use the three seashell system for liftoff?
Haha he doesn’t know how to use the three sea shells.
Uhh, one stargate doesn’t go anywhere.
that’s why you communicate via radio waves to other life in the area and build a network
You can accelerate it into space at g forces which would liquify living beings, perhaps?
Just frisbee those things in random directions until one works.
I’d say they stand a whelks chance in a supernova of that succeeding.
Actually I’m a marine astrobiologist and that chance is really really high
Using what?
(Remember the premise of this subthread is that they’re doing this instead of rockets.)
Bah, Stargates are just propaganda from the rocket first civs.
There is no need to send a gate in advance, just use your favorite teleportation mechanic.
I wonder at what point it is worth building a
space elevatorspace pyramid.Just keep stacking rocks until you’re a few dozen miles away from the edge of space.
Now I’m curious what would actually happen if a planet’s species dedicated themselves to making it happen, build a pyramid up to a geosynchronous orbit so you could theoretically throw something (or jump) and it’ll end up in a higher orbit.
The physics wouldn’t work, of course, but I’m curious exactly how things would go wrong and if there were engineering solutions available to get to the next big thing.
Like one thing is how tall can you get before the base encircles the planet (where trying to add more layers just makes the planet bigger and requires bringing in outside material, which means your geosync orbit gets farther).
Though as you add layers, the surface area increases, so your “pyramid” is actually getting wider as it gets taller, at least at the base.
Or if you can get really high without encircling the planet, how high can you go before affecting the centre of gravity? Could a large enough pyramid give the planet a wobble? Cause flooding on the near side and sea level drops on the far side? How high can you build a solid pyramid before the pressure of it all makes the lowest bricks get melty? Would it even matter or does the rest of the weight just hold it all in place? Or would a sufficiently large pyramid just explode because the sides would give out?
Assuming you had a perfectly strong material that could handle it, is it possible to build a tower to a geosynchronous orbit or will it keep moving away as you add mass to the tower? Would such a tower float in place if you kept building it out past that point and then detached it from the ground?
To put something in orbit, it has to go sideways very quickly. It has to rotate around earth, such that the free-fall causes the curvature of the circle. For Low Earth Orbit, that’s 7 km/s. You have to get it to that speed, just “jumping” isn’t enough. You’d need some kind of railgun or catapult.
You definitely wouldn’t want to do this all the way to geosynchronous orbit. Just getting it to the edge of space is already ridiculous to the point where it has me questioning how much pressure and heat the stone at the bottom would reach, and therefore how stable it would be.
And for a super earth, getting out of the soupy atmosphere is a challenge in of itself, so getting rid of that challenge would already be an incredible head start. From there you’d just need engines powerful enough to get you up to speed before hitting the ground.
Like one thing is how tall can you get before the base encircles the planet (where trying to add more layers just makes the planet bigger and requires bringing in outside material, which means your geosync orbit gets farther).
Gut vibe tells me that probably wouldn’t be a problem, as the atmosphere on any given planet, even a super earth, is only about as thin as the skin of an apple relatively speaking. And that’s all you’d need to beat here.
Could a large enough pyramid give the planet a wobble?
Absolutely. Though again gut vibe tells me it would probably only be a wobble of a few millimeters, nowhere near enough for anybody to feel it.
Assuming you had a perfectly strong material that could handle it, is it possible to build a tower to a geosynchronous orbit or will it keep moving away as you add mass to the tower?
I think at a certain point you’d be far enough up that you could reasonably just build a space elevator on top of the pyramid out of normal-ish materials like steel. The farther up you start the less of a foot you have in the gravity well, and the less distance your steel needs to support. At that point it would maybe be worth it do build a counterweight and go to geosynchronous orbit.
Another thing to keep in mind, if some civilization was crazy enough to do this, hopefully they’d be smart enough to do it around their equator to reduce the amount of pyramid of doom they’d need to build. But that would probably also mean bulldozing lots of countries and mass migrations.
yeah this idea actually exists, i think it’s called a mass driver, which is essentially a very high-speed rail gun, that shoots objects directly into orbit without the object having to have much of a propulsion system itself.
This obviously only works if the object isn’t slowed down by atmosphere, which means you’ll have to launch it from high enough up.
This is where the pyramid comes in. You can, of course, also utilize naturally occurring mountains, if your planet has any. These mountains would have to be rather high, though. Like on earth, maybe 100 km. The highest we have are 8 km.
Technically this is just a subtype of Verne gun. Which fun fact kinda existed. Back in the 60s HARP fucked around with a power charge based one down in Baja to achieve sub orbital space flight for a satellite.
Also Sadam Husein wanted to create one so do with that what you will.
Wouldn’t that much stone alter gravity enough to raise the atmosphere?
It definitely would, but I’m guessing you’d run into the issue of stability far before that.
I’m also guessing that the ratio of atmospheric extension to terrain extension would be on the side of terrain extension. Gravity is a rather weak force in comparison to the other forces of the universe.
This would be a fantastic xkcd “What if?” question if it isn’t already.
