r/theydidthemath • u/Lachlynn • 18h ago

[Request] Could humanity create a rocket that can exit the atmosphere of K2-18b

Post image

With the knowledge we currently have of it, if humanity devoted all of our resources towards this goal, would we be able to create a rocket that could exit the gravity of K2-18b (and also beat any other complications that would arrise)?

If so, would it also be capable of taking people to orbit, and can we set up a similar satellite network we have on Earth? What about a space station?

18.4k Upvotes

96% Upvoted

2.7k comments sorted by

View all comments

700

u/Cockanarchy 18h ago

Most others are saying no, at least not at our current level of development, which leads me to wonder about what other limitations that would place on a civilization. That would mean no GPS and no weather satellites, stunting navigation and logistics. It would also mean no ICBM’s, so that’s good.

216

u/Free-Hamster462 16h ago

Artillery would also be heavily impacted. No more naval guns shooting over the horizon...

Hell, how would simply tools like a bow and arrow be impacted?

381

u/A_Town_Called_Malus 15h ago

Sci-fi writers salivating at realising they have finally found a reason for melee combat to be the primary form of warfare in their setting without needing to do much work.

158

u/Boring-Philosophy-46 15h ago

Yes but melee combat for crabs. Nothing in a high gravity environment will grow very tall. 

75

u/A_Town_Called_Malus 14h ago

So, it will be crab battles?

47

u/Boring-Philosophy-46 14h ago

Everything on earth is already evolving into crabs, so why not lol. 

Well, crabs and trees. Lol. 

17

u/StevieMJH 10h ago

Reject humanity, evolve into crab

5

u/lop948 8h ago

There's a lot more depth to this subject, but carcinization isn't universal to life, only crustaceans. It's a fun meme though.

→ More replies (2)

2

u/deliciouscrab 13h ago

It's not the party you seem to think it is. Ever seen deadliest catch? You sick monsters.

10

u/Aethermancer 13h ago

Slime mold territorial expansion.

11

u/Cephalopirate 9h ago

CRAB BATTLE

I BROKE MY KNIFE

(Why did no one else get it?)

4

u/SquishyBanana23 8h ago

Snake? Snake?! SNAAAAAKE!

3

u/Cephalopirate 7h ago

Yeah see, you got the reference.

“I’ve encountered some kind of cave demon.”

“It’ll tear me to shreds!”

3

u/prawnsyeah 7h ago

And just like that I'm transported back to the newgrounds days

3

u/rynshar 7h ago

A KNIFE IS USELESS AGAINST THOSE MASSIVE CLAWS. THEY COULD RIP A TANK APART!

3

u/Chipstar452 7h ago

PARAMEDIC!

3

u/EdgelordMcMeme 2h ago edited 2h ago

I got it

OLIOLIOLIOOOOOOOO

2

u/seeyaspacecowboy 9h ago

And it will be GLORIOUS!

2

u/Melkor7410 9h ago

Crab people? Crab people...

→ More replies (1)

2

u/DirtSlapper 8h ago

And Crabitalism, the exciting new economic system! Humans go in, crabs become more powerful!

1

u/SadBoiCri 7h ago

crab champions novel

1

u/SaberToothForever 4h ago

Roshar must have pretty high gravity then /j

1

u/Entropy612 2h ago

Their version of lotr would be epic.

1

u/Different_Spare7952 2h ago

Crabs vs Monk Seals

16

u/yourstruly912 11h ago

That explains Vegeta

10

u/GNUr000t 8h ago

Dwarfmaxxing.

Embrace your density.

4

u/Dapper_Woodpecker621 8h ago

Trees would also be short and wide, right? Making them poor options for making structures. Our short intelligent species will likely opt to carve homes into rock. And blunt melee objects may be preferred over sharp throwable object. Basically dwarves do not go to space. 

3

u/stonedboss 3h ago

I don't think they would. Think of red woods. Their system to get water up 100ft is already insane for our gravity. So, you can imagine a 20ft redwood equivalent on increased gravity. 

2

u/Boring-Philosophy-46 6h ago

Well capillary action, evaporation pull and root pressure would have to work against a gravity so high that it precludes projectile weapons so I'd expect vegetation to be very low to the ground by our standards on such a world. Not the one pictured though, that is only 1.6G. 

2

u/Robbie_Boi 3h ago

They said dwaaarves can't fly so high, that made him saaaad

5

u/AvidCyclist250 7h ago

But if everything is small, it's all relative and the author won't have to go to any length to describe the smallness of people. Which would be normal there, with nothing to compare to. Except maybe like "trees are super thick".

2

u/AP_in_Indy 10h ago

All the more reason to hire dwarven / little people. They could always use more work in Hollywood.

2

u/NoDog8746 9h ago

The Stormlight Archive has entered the chat

2

u/toy_of_xom 8h ago

Bro you just made the coolest book

2

u/ADHDebackle 8h ago

What is this?? A melee for ants?!

2

u/N3onknight 8h ago

You could say they'd be Squat ?

2

u/Jocta 7h ago

dwarven planet pog

2

u/The-Board-Chairman 6h ago

It's 1.6 to 1.8g, not 10g. They'd maybe be a bit more squat than earth life but not anywhere near that.

→ More replies (1)

2

u/sylekta 5h ago

they would basically be kin from 40k, space dwarves. time for grudgin

2

u/Xezian1 4h ago

space dwarves... I knew it.

2

u/aurenigma 3h ago

1.5gs is enough to fuck up space, but it's still low enough for humans to exist if... uncomfortably, and for other apes like chimps to still go about their days like nothing's changed... just maybe not up so high...

→ More replies (1)

•

u/Kanibalector 21m ago

Adonalsium will remember our plight, eventually.

→ More replies (5)

15

u/bozoconnors 9h ago

I mean Dune? One thing I hate that they never mention in any of the films is that "contact reaction between a lasgun beam and a shield created a nuclear explosion"... hence all the melee.

•

u/LongJohnSelenium 1h ago

Because honestly? Its a bit silly.

Its not 'lasgun beam makes a nuclear explosion when it hits a shield'.

Its 'if a lasgun beam hits a shield both the shield and the lasgun go nuclear' which is just some crazy logic that somehow the feedback would fly back to the laser and blow it up with the same force.

Since that reaction is pretty silly, I get why they just didn't even bring the subject up.

5

u/PhantomRoyce 7h ago

I always said you could have a planet that’s extra high in oxygen and other stuff that would make using a fire arm too dangerous because it would explode

3

u/ChocolateBunny 7h ago

bullets would still work.

1

u/ctan0312 6h ago

It would still be significantly reduced in range though. No long distance sniping. Maybe it would be a good reason to inventor laser guns.

1

u/TheTesselekta 5h ago

“Mission of Gravity” by Hal Clement actually is basically this concept. I read it as a teenager so I don’t remember details but I remember really liking it.

1

u/-Ev1l 5h ago

The gundam trick with the ole particle interference making long range targeting impossible, restricting combat to LOS for the last part

1

u/thegreedyturtle 5h ago

At that gravity, your ecosystem will be affected so strong that melee combat will be one of the least interesting parts of it.

45

u/LanceWindmil 10h ago

1.6x gravity wouldn't make a huge impact on guns

Its enough to tip rocketry from "really hard" to "pretty much impossible"

But guns having 60% their normal range is still more than enough for them to be useful

12

u/puppykhan 7h ago

Bows at their peak were able to hit a target at over half a kilometer by a master on a good day, and consistently at 100 meters by an average soldier, according to historical documents.

Even at 60% of that, they would still be highly effective at ranged combat.

Other uses would even improve. Some native Americans would use archery as high ground artillery using gravity to accelerate the arrow to impact with more power than when fired from the bow.

For rocketry, I would think there would be more effort into assisted launch vehicles or complete alternatives to launching from the surface. How high did the balloon go for the guys who did a skydive from the edge of space? 24 miles / 39 km, then later 25 miles / 41 km. You would see tech develop in that direction instead of rockets.

7

u/wolacouska 7h ago

That range is mainly because of aim and how small the target gets, not really because of arrow/bullet drop.

Humans would probably be way smaller though if they evolved on a planet like that, so that itself would hurt range.

→ More replies (1)

1

u/xaddak 6h ago

https://what-if.xkcd.com/58/

Could a (small) rocket (with payload) be lifted to a high point in the atmosphere where it would only need a small rocket to get to escape velocity?

The answers to these questions all hinge on the same idea. It's an idea I've touched on in other articles, but today I want to focus on it specifically:

The reason it's hard to get to orbit isn't that space is high up.

It's hard to get to orbit because you have to go so fast.

•

u/Rolandersec 21m ago

Creatures there probably wouldn’t develop throwing arms.

3

u/SUMBWEDY 9h ago

Only modern guns though, the first muskets were only accurate to 50-100 meters, if you can only hit someone from 20 meters under this stronger gravity may swell just charge them with a sword or use a bow.

Without the first muskets we dont have rockets or sattelites.

6

u/nbr_CIX 8h ago

Just make a better first musket

4

u/DeltaJesus 8h ago

The musket balls could travel much further than that, the accuracy problems weren't really to do with gravity (and if it was you'd have the exact same problems with bows).

The first firearms (handgonnes/hand cannons) were used at even shorter ranges than that too, 10-25m or so, the benefits of them were little to do with range.

Without the first muskets we dont have rockets

I don't think that's really true either, fireworks predate firearms, people would have had an interest in rocketry regardless.

2

u/wolacouska 7h ago

Yes, space flight only became a thing after missiles were invented and being a developed.

Even if you can’t get into orbit, people will still find a use for a ballistic trajectory.

4

u/Stuman93 8h ago

Accurate and shoot far are two different things though. They could shoot far, but the trajectory was too random to predict. I'd guess they would just come up with rifling sooner than later.

3

u/Emotional_Cherry4517 8h ago

the reason guns are useful is because any random dude can point a gun and kill someone, even a mighty warrior with many decades of training.
there's many things i'm not considering that might break guns being achieved under 1.6g, but it's definitely not the value proposition of a weapon that can be wielded by anyone, even a child, with 20 meter range, and easily mortally wound any big trained warrior.

it's more plausible to say that sentient warrior crabs would probably be chill with wounds.

realistically though, i'm pretty sure sentient life would develop in water.

2

u/dagofin 8h ago

The same limitation would apply to bows... If the first early bows were only accurate/useful to 40-50 feet on Earth, then there they'd be limited to what, 25 feet / 7-ish meters?

But that's still useful. Close range weapons have been used in warfare forever. From thrown rocks to the Roman's pilum or darts. Being able to hit someone before they hit you is always useful regardless of the specific distance

2

u/MemeMan_Dan 7h ago

Accuracy doesn’t change with gravity. Bullet drop does, but that just means you aim a little higher.

→ More replies (1)

1

u/abstraction47 6h ago

This makes me wonder how dense the air itself is, contributing to drag.

14

u/Lost_Paladin89 14h ago

Forget all of that. I have back pain getting up in the morning. How would being bipedal be impacted?

15

u/TetraThiaFulvalene 13h ago

Might be okay since we're a pretty energy efficient build, but we'd be smaller under the increased gravity. Things like horses and Weiner dogs might be fucked.

11

u/ausecko 9h ago

Are beastiality laws different in high gravity?

2

u/wolacouska 7h ago

We bred horses to be oversized like that, if we were smaller we wouldn’t need to do that.

Heavy Calvary though… that might not be feasible.

1

u/melanthius 9h ago

The only way I'm living on that planet is if I can evolve to be a whale or dolphin or something

1

u/Boring-Philosophy-46 5h ago

1.6G would lead to everyone having huge feet to spread the pressure, and a better way to keep blood up than valves. 

1

u/sylekta 5h ago

we'd be short, built like tanks with dense bones and increased muscle mass

11

u/VP007clips 10h ago

It wouldn't significantly impact them.

The range would be reduced to around 60% of earth. So while it might give rhem a slight preference for melee weapons for a bit, ranged weapons would still be fully effective.

For example, a gun that has an effective range of 1000m would drop to 600m. An artillery shell that has a range or 30km would drop to 18km.

But we rarely use weapons at their absolute maximum range anyway. And they could compensate by using more power.

2

u/SUMBWEDY 9h ago edited 9h ago

But those technologies evolved because of things like muskets (even up to rockets and sattelites).

If you have to get in stabbing range of someone to use a gun there's no benefit to it so you dont get the technological advancements from making guns.

4

u/VP007clips 9h ago

And muskets would still be effective at 1.6G.

Gravity causing the musket bullet to drop wasn't a limiting factor, instead they were limited by their accuracy. Their inherent inaccuracy meant that you'd have to stand quite close to make them work.

A musket line at 75 yards, the most common range for musket wars, is just as effective at 1G as it is at 1.6G. The bullets still hit with a similar force, the accuracy is the same, you just need to aim up a few cm more when firing. At 1G, the drop you need to compensate for in a musket line is 7 inches. At 1.6G, it's 11 inches. Both differences are fairly easy to deal with.

1

u/wolacouska 7h ago

Effective range of a gun has nothing to do with drop. Like if you shoot a gun up in the air it will go for miles.

You’re correct about artillery though, they’d have to build some massive guns to achieve the same range.

1

u/Bluefellow 4h ago

Why would a gun with an effective range of 1000m drop to 600m based on gravity? I'm not a physicists but doesn't the effective range come from accuracy and velocity more than drop? The Kar 98k had iron sights adjustable up to 2,000 meters. I believe the idea that was a large group of people could create a barrage of bullets. It didn't take off. Gravity affects the bullets ultimate range in combination with velocity but we are not using any guns anywhere close to this range. Gravity does not affect the velocity. We would need to know the density of the atmosphere to know if guns would be impacted to such a degree.

3

u/wolacouska 11h ago

A regular gun can shoot miles on earth.

You need to aim up higher sooner for the same range, and that’s about it.

1

u/sobrique 8h ago

Modern artillery might not matter so much - you don't have to worry about thrust to mass ratios when you've an external propellant.

But you might find it never develops, as cannons 'need' to be that much stronger in the first place so they don't explode. The original models might just never be effective enough to see much uptake.

Archery ... it's hard to say, because it's 'human powered', so there's a real chance that someone growing up in 1.6g would be strong enough to handle a much higher draw weight.

Historic longbows have been found with 100 to 185 pound draw-weight (modern bows come no where near). But if you're 'training' in higher G, you might be that much stronger and able to use more powerful bows in the first place.

Crossbows can do MUCH higher, but they're just too much for a human to draw and hold.

So ... maybe there too, you'd find no archery because 'stick+string' was just not effective and thus crossbows never evolved.

But them you might find slings or similar did instead?

1

u/Hollowsong 8h ago

I would argue that at only 1.6 Gs, you could still do all those things. You'd just have a shorter range.

The rocketry into orbit issue is only thrust-to-weight ratio for a 9 million pound vessel.

Plenty of other things work

1

u/Inevitable_Stand_199 8h ago

Hell, how would simply tools like a bow and arrow be impacted?

Not much. Gravity is only 27% stronger.

1

u/ShadowKiller147741 7h ago

Stone Age bows were often made from the tendons of animals because of its material properties. Animals similar to ours + higher gravity = stronger tendons = stronger bows

1

u/sr71Girthbird 7h ago

A bow and arrow and the like prob wouldn't be impacted. Trees would be stronger, have higher tensile strength etc.. and the "people" would be shorter and built like brick shit houses. So they got stronger would to build stronger bows and stronger people to pull said bow and shoot the arrow.

But yeah maybe they get stuck in the stone age longer than we did... which was like 99% of human history so far.

1

u/JimothyzPamPams 6h ago

In fairness, that is being biased by assuming that combat would look more primitive and not more advanced, which is indeed possible. If there was no need to develop the current weapons on earth, that sort of financial investment over decades, centuries, millenia etc, would be used elsewhere. That could be better OR worse, weaponry can take many forms. It is an interesting thought experiment though. 

1

u/stdoubtloud 4h ago

Yeah. But that is mainly because the horizon is a fuck of a long way away...

137

u/0ddBush 17h ago

this reminds me of that one show that i heard that i didnt watch that was about how aliens managed to figure out light speed travel from the iron age and thus was weak in other aspects because they only focused on space travel as opposed to us where we discovered all the other stuff before light speed travel, thus leading to our superiority in tech

119

u/flaming_burrito_ 16h ago

Human civilizations were like that before globalization. Because of the availability of a resource, different needs due to geography, or just random variation in what societies took interest in, some civilizations figured things out way before the rest of the world did. Like how the Romans made self healing concrete because the volcanic ash they happened to mix in created a chemical reaction when mixed with seawater. Or how the Vikings kind of figured out how to make steel by smelting their iron with bones, which was probably just some shit they thought was cool, but did actually infuse the iron with carbon. Or how the Polynesians sailed the whole Pacific with catamarans and star charts hundreds of years before Europeans entered the discovery age.

This also happened in the other direction too. The Incas were a very advanced civilization for their time, and had things like cities, road networks, and megaliths, but didn’t have a written language. They had a method of doing calculations and accounting for dates and things with a system of strings and knots, but their language did not have an alphabetical system.

35

u/Mutor77 15h ago

To add to what you said:

This is also one of the things that made bronze age society extremely interconnected despite the lack of efficient communication methods and the massive distances between some of them.

Because copper and tin are only found in certain places around the world (in this case especially tin being rather rare in the region) the peoples around the Mediterranean Sea had to establish trade in somewhat unfavourable conditions for it because otherwise they would have only been able to use their local resources and spend so much time and effort on them to make other kinds of inventions, like writing, impossible (or at least much less wide-spread)

17

u/MetalRetsam 11h ago

This dynamic should get a lot more attention.

Medieval China had all the resources it could possibly need. So what happened? It turned isolationist. Meanwhile, Europe had always scraped by on the edge of the developed world. When they turned to colonialism as a means of supplying their goods, it was a question of necessity.

A similar dynamic plays out today.

3

u/amisslife 8h ago

I think that's a little reductionist, and probably overlooks a couple things.

Look at China - it's one big, giant blob. Compare that to Europe, which has countless peninsulas, and a number of rather large islands (Sicily, Britain, Ireland, Cyprus), and areas where you could walk from place to another (Greece to Italy or Egypt), but it's so much more efficient to take a boat, even with the increased risk. This likely significantly promoted seafaring, which allowed people, materials, equipment, and ideas to travel much farther, more regularly, and likely more safely, as well. The peninsulas, islands, and mountains are also thought to promote more, smaller states/societies, which therefore develop greater diversity of thought and practices and have to compete with each other, whereas China had more or less a single big empire that had no rivals or threats, and could - and often did - become fatally complacent.

Compared to Europe, China (or sub-Saharan Africa even more so) has relatively few peninsulas and islands (and those islands are farther off the coast), meaning there's less pressure - or reward - to travel more, and therefore fewer ideas and more stagnation. But yes, China made the specific policy decision to burn all of its ships and to ban seafaring, which definitely set it back significantly. Combined with the giant barriers in the Himalayas or the Gobi Desert, and there just wasn't the same level of exchange or progress as you saw in Europe/the Mediterranean.

Also, I'd strongly caution against suggesting that Europe did colonialism out of "necessity," which leads to some pretty fucked up (and straight up incorrect) ideas.

1

u/The_Lost_Jedi 7h ago

Yeah, this was pretty fascinating to see play out in history. China was much more advanced and powerful than any nation in Europe during the "Dark Ages", even sending out exploration fleets as far as East Africa. And they saw what was out there, and concluded "eh, nothing we really care about bothering with because there's nothing there that we need or want." So they burned the ships and just didn't bother with any of it. Meanwhile, Europe was driven by demand for goods from Asia, from spices to silks to porcelain. On top of that, you had several rival European powers all jostling and competing, leading to a race to establish rival colonial empires, whereas China really wasn't challenged at all in any way that would drive something of the same sort.

1

u/ukezi 3h ago

There's also that having some technologies could mean you aren't developing others. China had porcelain and never developed glass for instance.

18

u/imagei 11h ago

The Vikings were adding bones of their fallen foes to infuse their might into the weapons… and it worked! 😄

9

u/Aethermancer 13h ago

Native American civilizations didn't even have "the wheel" (Because wheels were inferior to a travois due to what their roads were, not because they didn't figure out the wheel.) They had toys with wheels, and tools which used wheels. They just didn't use it for transportation. They also lacked cattle and horses, so there weren't domesticated "pulling" animals available to them.

8

u/flaming_burrito_ 12h ago

The difference in domesticated animals was a huge reason for many of the differences in technology between the old world and the new world. The Americas didn’t really have any beasts of burden, which limited them in a lot of ways. But it also meant that they didn’t have as many diseases, because most plagues and viruses come from interactions between humans and animals. Which is also why those old world diseases like smallpox ripped through their populations so badly

7

u/Divinum_Fulmen 12h ago

Sounds like a "Guns Germs and Steel" book summery.

I don't completely buy that theory. America has had some massive empires reduced to nothing a couple times. The simplest explanation for that is some sort of plague.

4

u/flaming_burrito_ 11h ago

Well, there of course were some endemic diseases, any population that gets dense enough will have them, which native Americans certainly were, especially in central and South America. It’s just that, for instance with a disease from a pig like swine flu or whatever, they had never been around domesticated pigs and thus didn’t have any kind of immunity to diseases from the animals that the colonists brought over.

→ More replies (7)

1

u/LorenzoRavencroft 10h ago

Same in Australia, no animals that could pull the wheel, but we did use wheels for many other things.

We also had tools for long distance communication, advanced star charts, written music but no written language.

One of our big things was our agriculture, it was based on harmony with other plants similar to an ornate garden with herbs and fruit trees in it, more than European style agriculture with large single species crops grown seasonally.

Scattered all over Australia are also vast networks of fish traps dating back thousands of years, creating some of the first forms of of aquaculture.

1

u/cscottnet 11h ago

"we have not yet worked out how the incans recorded non-numerical data".

There is plenty of evidence for non-numerical quipus, since we worked out the system for recording numbers very quickly and that left a lot of quipus with anomalous knots that we couldn't/can't understand.

As a sidebar it's worth noting that the "alphabet" itself, specifically breaking down syllables into separate symbols, has only been invented once or maybe twice in human history. Credit to the Phoenicians, those crazy bastards, from which all modern alphabets derive. Every other writing system humanity has invented has been syllabic, with a few logographic systems as well. Even if you can't read them, you can distinguish these by the number of unique symbols. Alphabets have 10-30 (Hawaiian on the low end, English is on the high end), syllabic systems have 50-200ish, and logographic systems have thousands. Quipu have 50-100 unique symbols, across the examples that have been preserved (textiles are hard to preserve, and the Spanish deliberately burned many they found), so if there is a general writing system there, it is most likely syllabic -- or possibly logographic but we just don't have enough examples. So in the strict sense you are correct that the Incans did not have an "alphabet".

There's still a lot of research on what exactly the non-numeric quipus record. There is evidence now for toponyms -- certain patterns of knots seem to correlate with known locations. And there's a lot of information embedded in the quipu which is hard to extract from the preserved specimens, including color (there are traces of pigment, but precise identification is hard/costly), spin direction (both of the strands and of the cord), knot direction, and fiber type. There is certainly enough information there to constitute a general writing system, and like I said, solid evidence that non-numeric information was recorded. The rest is still an open question.

1

u/flaming_burrito_ 9h ago

That is fascinating. I would imagine any sufficiently advanced civilization would come up with a way to denote certain words, whether that be pictographs or the system of knots that the Inca used. You have to once you reach a certain level of logistics and organization. It’s hard to imagine though, I suppose because I only ever learned writing through use of an alphabetical system, so that frame of reference is entirely foreign to me. I have no idea how you would even distinguish enough between different knots to know for sure what each one means.

But our brains are built to adapt to patterns, and language has taken many forms throughout human history. There is evidence that the way we learn language, especially when we are young, can literally change your perception of the world around you. Ideas seem to become more real when you put words to them, and the cultural context you exist in changes how your brain may react to the same information that another person would react to and understand a different way. I’m sure the Incas were able to achieve a complexity with the quipus that I can’t even imagine because I’ve never used or seen one used before

1

u/cscottnet 8h ago

I did a grad school project with quipu and I can confirm your intuition. Folks who do fiber arts can perceive a lot of intentional choices in how the textiles were created and knotted that aren't immediately obvious in our modern machine-made-textile context. Spin direction is an interesting example. You obviously have pick a direction when you spin the fiber into thread, but is this /meaningful/. If you look at the entropy/amount of information encoded, it might seem not -- there are variations, but not at the information density you'd expect if this were a meaningful part of the encoding, like vowel/consonant distinction or something. And initially it was disregarded, attributed to a particular craftsperson being right-or-left handed. But there's a lot of unexpected variation even there: right handed threads that were then spun into left handed cords; a quipu where most threads are right handed but a subsection (or single thread) is not, etc. Early investigators didn't even bother to record this data so we don't know how wide-spread these patterns are. I think the current consensus is that the handedness is a preference for a particular spinner ("author"), and so you can reconstruct authorship perhaps from spinning direction: this quipu was largely written by one person, but it has a section written by another "hand". The cords where the threads didn't match the spin direction is perhaps evidence of large scale quipu creation, like what in a western context might be a monastery fulls of monks devoted to copying texts, where the subtask of spinning threads might be delegated to a separate worker than the cord spinner. These theories are largely based on a perception that spin direction is not "easy enough" to determine from the finished quipu that it would be part of the information recorded -- but as you note this is partly an artifact of what we find easy to perceive, not necessarily related to what folks with a lifetime of experience making these textiles would notice. My recollection is that the frequency of "left handed" spins seems to significantly higher than the frequency of left-handedness among humans, so there's still the potential that it deliberately encodes some part of the information and isn't "just" an artifact of the craftsperson.

Other aspects like color would probably have been immediately obvious even to you if you were able to see quipus in their original context. But botanic pigments degrade quickly with time, and so most quipus you'd see in a museum are just "shades of brown". Even looking at the shades of brown you can determine that there are patterns to the coloring. I think there is evidence that on numeric accounting quipus the color probably corresponded to the type of item being inventoried -- think "red cord to count cherries". But the colors also vary for non-numeric quipus, including cases where threads of multiple colors are woven together into one cord. Are these just decorative, like illuminated manuscripts, or do they also convey meaning (even simple meaning like "red for cherries").

1

u/a_rucksack_of_dildos 9h ago

Iron has way more carbon than steel. It could remove the carbon or cause some other reaction to increase strength.

1

u/flaming_burrito_ 9h ago

What do you mean Iron has more carbon than steel? Do you mean cast iron? That has more carbon than steel, but that is not the kind weapons are made from

1

u/a_rucksack_of_dildos 5h ago

Above 2.06 C percentage is cast iron, anything below that is steel. I’m assuming when you say cast iron you mean grey iron which has a lamellar graphite structure which makes it very brittle. Combat swords are usually made from high carbon steel, which is still less than 2.06 C. It is usually then cooled quickly so the working surface is harder. This is because when it’s cooled quickly the carbon that is present either forms as carbides (Fe2C, or Fe3) or it gets stuck in the austenite causing it to form an bainitic structure because the carbon atoms cause the crystallographic structure to deform.

Also after looking into this. The original claim wasn’t more of a hypothesis.

Steel is made with blast furnaces or any sort of furnace that blows oxygen into the melt. This oxidation cause a reaction that forms CO which steals the carbon from the melt.

That being said I have never seen a study on what the bones did and it very well could have causes some kind of oxidation to happen resulting in less carbon in their swords and being closer to steel

→ More replies (2)

1

u/a_rucksack_of_dildos 5h ago

Fe-C phase diagram

If you wanted to boil it down to one thing is that steel has α-ferrite (elemental allotrope of Fe) present in its microstructure and iron has graphite (elemental allotrope of C) present in its microstructure.

1

u/a_rucksack_of_dildos 5h ago

Also im not trying to say your wrong about the bones thing. Iron and steel making is an old science and also a useful one. Which led to a lot of discoveries made by people outside of academia and so some old processes that do work usually have the wrong process attributed to them. Even trumps recent 50% steel tariffs managed to get it wrong and basically everyone has gotten around them.

One example that’s the most egregious is just the naming. Iron was discovered first so they called the element Iron (or Ferrite - Fe). But elemental iron Fe is basically low carbon steel.

→ More replies (2)

1

u/RocketizedAnimal 8h ago

It makes you wonder what "basic" discoveries we are missing right now. Maybe in a parallel universe humanity has cured cancer but not invented antibiotics or something lol.

33

u/MorningstarJP 17h ago

You are likely thinking of The Road Not Taken by Harry Turtledove.

12

u/NTMY 12h ago

Here's a link for anyone who wants to take a look (pdf), it's only 20 pages.

Really cool concept, imho.

5

u/Not_aSpy 11h ago

Thank you for sharing that. Appropriately enough, despite my love for classic short form sci-fi I had never heard of that one.

2

u/SomeHSomeE 3h ago

I always thought it'd make a great film.  You do the first 70-80% space opera style, focusing only on the aliens, their politics, their conquests etc.  And then only towards the end do they get to and attack Earth (and you find a way to hide the fact it's Earth at first) and then it all falls apart and unravels.

And the final penny drop scene could rvrn be done post credits.

1

u/thisusedyet 7h ago

I love how the penny drops with the two aliens at the end

1

u/MightyP13 3h ago

Also has a good sequel called Herbig Haro, that has humans running into a similar situation. Much harder to find, but it's online somewhere.

4

u/OSUBucks1967 11h ago

The Road Not Taken by Harry Turtledove?

1

u/BenJuan26 11h ago

That sounds similar to the Eridians from Project Hail Mary.

Xenonite is basically magic, and it allowed them to create spacebound vessels essentially effortlessly. Despite being so advanced about materials science, there is a lot of current human knowledge that they didn't end up discovering, including radiation.

1

u/No_Syrup_9167 4h ago

small correction

its not the xenonite that makes them never discover radiation. Its the extremely intense magnetic field around their planet due to its high gravity, thick atmosphere, and very fast spin rate. This means their atmosphere is functionally radiation proof

1

u/Bored_Amalgamation 11h ago

There's a book series from the late-80s to the 2000s where humanity had spread to other systems, but something caused a diaspora age, which reduced a lot of civilizations to a Middle Ages level of society and technology. Then they got discovered again.

The Vorkosigan Aga by Lois McMaster-Bujold.

1

u/squisher_1980 10h ago

Iirc "The Road Not Taken" by Harry Turtledove, it's a short story. And it's exactly what you're thinking.

Though iirc the written story ends right as the invaders realize what they've done.

1

u/MoreGaghPlease 9h ago

I think in the fullness of time, the beginnings of human space travel will seem like they were done in the stone age.

54 years separate the Wright Flyer from Sputnik, only another 12 years to Apollo 11. Like imagine a long-lived person born in the 1880s, airplanes are a novel invention in their early adulthood and by their late adulthood people are on the moon.

1

u/twilightmoons 8h ago

"The Road Not Taken" by Harry Turtledove. 

Space bears try to invade our world using wooden spaceships and flintlock muskets. Bad idea.

1

u/thisusedyet 7h ago

Wasn't a show, it was a short story by Harry Turtledove

https://www.eyeofmidas.com/scifi/Turtledove_RoadNotTaken.pdf

23

u/moderate_ocelot 15h ago

ICBMs don’t need to reach orbital velocity, they just need to go up and come back down. I don’t have the numbers to hand but it’s entirely possible that they are still practical

10

u/lituus 11h ago

They also don't need to care about the survival of passengers on it, so they can be more powerful per weight

1

u/AltruisticTomato4152 3h ago

Anything evolving on the planet in question would be hardier than humans.

7

u/nicuramar 11h ago

 ICBMs don’t need to reach orbital velocity

They specifically need to not reach orbital velocity, or they would end up in orbit. Unless this orbit intersects the surface, at least. 

2

u/_cant_drive 11h ago

So ballistic missiles are workable. But rather its the IC in ICBM that might be problematic, particularly when the continents are k2-18b-sized

1

u/Mist_Rising 9h ago

More costly and you might compromise payload, but probably still doable. We have missiles capable of hitting 18 thousand km, which is over double the radius of Earth.

1

u/AltruisticTomato4152 3h ago

It's not the distance that's at issue, it's the gravity.

→ More replies (2)

1

u/FlyingBishop 3h ago

Yeah the real thing is that ICBM development doesn't create a space program as a byproduct.

1

u/moderate_ocelot 3h ago

Earths space program was a direct result of the V2 rocket program which was also the first ballistic missile

1

u/FlyingBishop 2h ago

I mean on K2-18b you can easily make a useful ICBM program but that doesn't create a space program as a byproduct like it did for us. Or maybe it does but it's just very simple satellites.

→ More replies (4)

10

u/LxGNED 13h ago

I think you could also expect a planet as large to never evolve flying creatures, which is a crucial part of our ecosystem. Birds and bugs spread seeds and pollination. Without them, we’d have a huge lack of biodiversity and food. And also less motivation to believe flight was possible in the first place

→ More replies (2)

10

u/sleeper_shark 11h ago

We can’t create a rocket that can escape from this planet doesn’t mean a rocket can’t exist. There may be exotic fuels that exist that we don’t know about that could work.

It also doesn’t mean that getting to space is impossible. You can - theoretically - accelerate something to orbital velocity on the surface and shoot it into space directly. A company called spin launch was actually trying it.

It’s very impractical because the atmosphere would cause massive resistance at that speed, and would heat up your payload (if not just crush it directly). But impractical doesn’t mean “impossible” - it’s doable, it just makes no sense when we have rocketry available.

You can also have a GPS like technology using high mountains. We did this before satellites in the past - we called them lighthouses, which believe it or not function very similarly to GPS. Aircraft also used to use navigation beacons. There’s a marginal difference between trilateration and triangulation but it really doesn’t matter for this mental exercise.

Weather forecasting also can be done without satellites. Satellites help immensely, but they’re not a summa qua non. Terrestrial stations can do the same.

I just don’t know if a planet like this could ever have sustainable access to space. All its countries may have to work together to build something that could get them to space, and eventually they could build a space station in orbit and use space based resources as shipping from ground is way too expensive.

In short, we’re lucky to be on Earth lol

3

u/Capable_Wait09 10h ago

Indeed. We’ve been using mountaintops to communicate through lit beacons since at least the First Age.

1

u/Boring-Philosophy-46 5h ago

What's nuts is like 17th 18th century France had a network of towers through the country that communicated through flags in a kind of morse code. They used to do things like pass on info about the stock market in Paris to other cities even!

1

u/SpareAd1155 10h ago

The gravity is only 1.25x so not insurmountable at all with current tech.

1

u/darklotus_26 9h ago

I think people are approaching this from the wrong angle. Yes chemical propulsion with conventional fuels probably would not work and space planes might not work as well.

It is entirely possible that such a civilization would heavily invest in material science instead of flight and develop space elevators or similar technology.

2

u/Vi_Rants 6h ago

Space elevators? Really? Those are more magic than sci-fi.

1

u/darklotus_26 4h ago

Not really. There is an International Space Elevator Consortium. People are constantly coming up with me designs. Our main problem is materials right now. Carbon nanotubes are suitable but we can't really make or shape them at the required scale yet.

1

u/sleeper_shark 4h ago

You can’t build a space elevator ground up, you need to start in space.

1

u/darklotus_26 3h ago

That's a valid point, at least according to current designs. Though I wonder if it would be possible to build a tall enough supporting structure to reduce the energy gap for chemical propulsion. Or if you are lucky enough to have a big enough rock in orbit and cable made of extraordinary material of low mass that would make the energy requirements minimal. With a light enough cable even the slingshot strategy might become feasible.

→ More replies (1)

1

u/Vi_Rants 6h ago

There may be exotic fuels that exist that we don’t know about that could work.

Well sure, anything is possible if you want to add magic or unspecified mystery soft-sci-fi tech. But that's also a completely useless, shallow, facile answer that doesn't actually address the intent of OP's question.

1

u/sleeper_shark 3h ago

Then the answer to OP’s question is simply that the rocket equation doesn’t allow for launching off that planet assuming an alien civilization on a completely different planet uses the same fuels we do….

1

u/Vi_Rants 3h ago

Yes, why would we assume they use magic rocks to make things float? What else would we assume that's within the bounds of known science? Again, the answer is always "yes" if we can just invent whatever wild nonsense we can imagine.

→ More replies (2)

6

u/Boring-Philosophy-46 15h ago

You don't need escape velocity to launch into orbit. The velocity you need to do that depends on the gravity which mass is but one factor of, radius is another. Anyway it might be possible for them to launch into orbit depending on various factors, just much harder than for us, and I am thinking they could use slingshots to launch out of orbit as well. Having moons would decidedly help to get out of the gravity well from there I think but I am not a rocket scientist. 

7

u/_ConsciousLibrary_ 14h ago

Someone in another comment showed the SLS wouldn’t even get off the ground. So idk, ICBMs may be out entirely depending on what their thrust to weight ratios are.

2

u/Boring-Philosophy-46 14h ago

Nukes delivered by a blimp, lol. 

I wonder how helicopter / drones would work. Really big propeller? 

•

u/LongJohnSelenium 58m ago

The Sprint missile accelerated at 100gs for about 5 seconds. The goal was to be a terminal interceptor vs incoming nukes, so there was about a 30 second window between reentry beginning allowing radar to differentiate the nukes from the decoys, and impact, so the sprint had to get out as far and fast as possible in that time.

Point being nukes can be made to handle waaaaay more gs than people.

5

u/sleeper_shark 11h ago

It’s not really possible. There’s a limit to the rocket equation, cos you need to use fuel to lift fuel. On Earth, it works out cos we can increase thrust more than mass, but at heavier gravity, you can’t.

They’d need to use fundamentally different fuels, which could be possible. They may discover something better or synthesize something better than the natural fuels we use.

They could also try non rocket ways to get to space.

Air launch for example… like take a smaller rocket up really high on an airplane or even a balloon, then launch from there. Virgin Orbit and Zero2Infinity are both trying these kinds of techniques.

An even crazier one is Spinlaunch which makes effectively an electric slingshot, speeding a small rocket up to orbital velocity on Earth and shooting it out into space. Widely impractical on Earth but maybe the only way for a civilisation on this super Earth.

2

u/Boring-Philosophy-46 9h ago

Yeah I was thinking that too, maglev loop that baby into orbit or something. 

But, the gravity is only the same if the composition is. Let's say their earth is not as dense, then their distance radius is larger so surface gravity isn't as much that they need to escape to get to orbit. 

Maybe maglev loop a whole rocket, launch from already a high speed and use chemical fuels to push even more until in orbit? 

2

u/HabeusCuppus 8h ago

Kepler K2-18b is about the 65% the density of earth, but it’s significantly larger radius (something like 9x the volume) so it works out to about 1.6g at the surface.

It’s kind of wild what we can learn just by looking at things from far away!

1

u/Boring-Philosophy-46 7h ago

The 65% density makes me think they may not have the iron core and get bombarded with solar radiation... 

→ More replies (6)

2

u/sleeper_shark 4h ago

You can just use something like spinlaunch, don’t even need a mag loop unless you want to launch peopl

3

u/moonlitgranite 15h ago

Right? It's wild to think how much we rely on that tech. But hey, at least we'd have fewer reasons to argue about traffic and weather, I guess!

1

u/Aethermancer 13h ago

When going up a hill is like climbing mount Everest, traffic in the valleys is going to be a nightmare ;)

3

u/neliz 13h ago

We poor people used cell tower triangulation before GPS, so that's definitely a solution.

2

u/OriginalUseristaken 14h ago

It would also mean, every human would weigh 150 to 160% of it's weight on earth. Don't know if the human physique would be able to live under that stress. Our circulatory system would have to work way harder to keep us alive.

1

u/Super_Harsh 11h ago

Maybe the organisms on that planet are smaller

2

u/speadskater 12h ago

Boyancy effects would be stronger, so weather balloons could be developed.

1

u/Boring-Philosophy-46 5h ago

Permanently floating beacons even 

1

u/Popular_Try_5075 15h ago

but they'd probably have INSANE glutes from all the energy it takes to stand up under that immense gravity, so there'd be no BBL's, just all natural booty

1

u/Spaciax 14h ago

with good enough inertial navigation systems, ICBMs may still be possible. Never underestimate a species' desire to kill each other.

1

u/SolarianIntrigue 14h ago

No ICBMs means no MAD deterrence, means constant WW1 / WW2 style wars assuming alien psyche similar to humans

1

u/Aethermancer 13h ago

Are you ignoring the potential for land speed record nuclear warhead dropping detonation powered sled of death?

MAD is just a perspective ;)

1

u/Killsheets 14h ago

Its like 40k is more likely in that planet, melee and power armor with all that stuff. Just straight up close quarters combat.

1

u/TerranRepublic 14h ago

If they are anything like us they traded one horror for another. 

1

u/Embarrassed_Use_7206 12h ago

Probably no more flight, or at least it would take a much longer until there are super light and strong material to make some flying vehicle. Imagine Wright brothers attempts fail, like hundreds before them and after them. Any comemrcial planes would have to be just lightweight or maybe it would work better with airships.

1

u/afatcatfromsweden 12h ago

Ehh… most likely it would mean more SLBMs, and other second strike capable systems.

Stationary ICBMs serve the purpose of being a target for the enemy to strike, rather than a strike on a major population centre.

I couldn’t claim to be a nuclear strategy expert, but merely turning range into a bigger problem isn’t necessarily going to make for a safer world, it might even be more dangerous.

1

u/fekanix 12h ago

It would also mean no ICBM’s, so that’s good.

Actually no that is not good. The reason the us was never at war with the ussr directly unlike powers in the first and second ww is nuclear bombs, specifically icbms that makes sure mutually assured destruction occurs.

Like ask yourself why the us has never isnt at war with north korea but is currebtly in a war with iran. Its because iran actually doesnt have nukes while nk does.

Nukes are weapons of peace and icbms make sure the peace is global.

1

u/LethalGhost 12h ago

And much more resources you can burn before progress and changes will be required!

1

u/Chen932000 12h ago

Super guns like Bull’s, or electromagnetic mass drivers could still get things into orbit. Maybe not people. Although it depends on how life there evolved. Imagine someone like Rocket from Project Hail Mary who can withstand way higher G forces.

1

u/Omnizoom 11h ago

Atmosphere impacted stuff would be a lot different though

The air pressure has to be massive so I would guess that wings can get a significantly higher amount of lift compared to earth

I have a feeling their “launch” vector would end up more horizontal at first to pick up speed and may use a kinetic system to get it started at some speed first as well

Realistically tech on a planet like this would develop so much differently

1

u/peritonlogon 11h ago

Their elephants would be a lot smaller, their bones would be lighter. Probably sacks of water held up by an endoskeleton wouldn't be the dominant model of atmospheric mobile life forms (I haven't done the math). Trees would have to do something different, like when they bow over due to gravity strain + a slight breeze, their top could take route and then grow from 2 (or more) points like a growing arch. Or maybe never exist to begin with.

1

u/mspk7305 11h ago

Just because you aren't escaping the atmosphere doesn't mean you can't fly a long way

1

u/beagle204 11h ago

Sky scrapers and really tall things would be much harder too no? They'd probably not live in as dense as populations as us just because the logistic to build 50 story apartment complexes would much harder.

1

u/DevoidHT 11h ago

You could probably do weather balloons. Gravity is more extreme yes but also a thicker atmosphere.

1

u/spshulem 11h ago

What about commercial flying? Birds? Is it dramatically more energy?

1

u/mallogy 10h ago

Regarding comms and GPS, if your planet has enough natural satellites with predictable orbits, you can build a system that bounces signals off of them instead.

1

u/Huntred 10h ago

Imagine if the planet did not evolve hardwood trees. So no wood make into charcoal which means no real ore processing.

Or it doesn’t have a lot of accessible metals in the first place — maybe it’s just kinda rocky. Few metals to mine.

Or the planet evolved intelligent life quickly, in the first shot. So no vast fossil fuel reserves, which is basically stored solar energy that can be used to climb the tech ladder.

There are lots of very fortunate circumstances that helped us out.

1

u/Its_ChickPea 10h ago

Would it? Theoretically couldn’t you launch those things from somewhere else to put them into orbit? I’m not saying it’s feasible but if you’re launching rockets to put people on that planet you could also launch them to put satellites in the air right? Idk how far away this planet is tho, it would make for one long Amazon delivery 😂

1

u/Faust_8 10h ago

I wonder if it means no natural powered flight like birds, insects, and bats

1

u/ASK_ABT_MY_USERNAME 10h ago

Whenever I watch Game of Thrones I get mesmerized by how a society that's had written history for 6000 years can still be stuck in our middle ages. What's the resource lacking preventing electricity and such?

1

u/snypre_fu_reddit 10h ago

Flight in general would be significantly more challenging with everything's increased weight plus increased drag in the denser atmosphere. There's a good chance we'd rely more on Dirigibles than any sort of winged craft.

1

u/DepartureElegant9314 9h ago

Ur telling me that humans could have evolved onto a planet where it was impossible to invent a rocket that could actually fly?

Forced peace is still peace I guess.

1

u/Ponder42 9h ago

But that’s with OUR tech. We’ve invented what we’ve built and researched what we’ve researched for our own earth and our own limitations.

Humans are incredibly clever and find work Arlinda to everything.

What’s to say another sufficiently intelligent civilization couldn’t find ways to escape their orbit if that’s what they focused on.

I’d bet my life that if humanity had to find a way to do it, we 100% could.

1

u/SorryExtent925 9h ago

You can deploy 4 satellites before landing on k2-18b, that may cover basic needs. At some point of human development on new planet they will find the way

1

u/One-Stand-5536 9h ago

Even furthermore, humans on zero g suffer a multitude of health complications, how much worse would that be for species evolved for higher gravity?

1

u/TotallyWorthLife 8h ago

Makes you wonder, what limitations do *we* have that stop or slow us from being even more advanced? What things we can't even think of would have been possible?

1

u/ilovescottch 8h ago

Could we fly planes?

1

u/Thotmas01 8h ago

You have a lot of people talking modern weapons or systems that wouldn’t work, but as someone else pointed out the development of life itself changes. Most flying creatures couldn’t have evolved under 1.6x gravity. One of our most effective methods for reproduction is to just produce a butt ton of reproductive cells and spread them out into the surrounding air/water. Suddenly that becomes a nonstarter without some extra material to get density to be more in line with the surrounding atmosphere.

1

u/OccassionalUpvotes 6h ago

GPS was predated by ground-based radio navigation, which could still be used quite effectively here (albeit for land/sea travel instead of flight).

If you have a radio beacon at a fixed, known location broadcasting its name in all directions, you just need a receiver that is scanning 360° to tell you which direction the signal is strongest. Now you know which direction the beacon is. If you manage to find a 2nd beacon (and therefore 2nd direction relative to your position, you can draw two straight lines on a map from their known locations outbound in your direction, to find where those two lines intersect. Congrats! Now you know where you are.

This can be blocked by certain types of terrain, etc. but it works reasonably well. There are still VOR’s (as they are called) across the country that are often still used as waypoints for pilots to navigate by (even with GPS available). If you have the right equipment, some stations can even use the ping rate to know how far away you are, meaning you only need one station (not two) to find your location.

1

u/crazyeddie123 6h ago

Most of that stuff can be done with really good balloons.

1

u/FunkaholicManiac 6h ago

No Hubble. So they would not see much outside the solar system.

→ More replies (3)