56

Internal politics. There was a period where the politicians made bigger and bigger messes and the voters grew more and more impatient with them. It seemed like everybody was corrupt. A new party called the Openness Party appears. They have a charismatic leader and win votes with a simple promise: "No more secrets!" It starts as a local party and wins the ...


47

Large scale albedo changes Albedo is the reflectivity of solar radiation off the surface of a planet or moon or something. It represents how much of the solar radiation is sent back into space as opposed to how much is retained. The planetary albedo of the Earth is about 0.367. However, this varies greatly from place to place. Cumulus clouds and fresh ...


44

•98% of all the landmass is wasteland/desert •The two poles are some big chunks of ice, each covering about 20% of earths area This is rather confusing. Yes, I get that there are also cold deserts, but next to the glacier there will be the melting zone, where the bonanza of water will inevitably favor life. •There are only two climate zones, hot ...


42

Not possible TL;DR In order to ensure that an ICBM had only a 5% chance of surviving for 20 minutes in space, you need to launch at least 5 orders of magnitude more mass into space than has been launched since Sputnik. This is not economically feasible, so Kessler syndrome cannot protect you from ICBMs. A note on ICBMs First we have to define what an ...


40

How would this difference affect Earth's overall chemistry? Not much (but see below). Here's why: Let's start with some background The core–mantle differentiation event was the melting event which caused separation of the rocky mantle and the metallic core. It separated earth into two phases (in the chemical sense): Metal, which is dense so it sank to ...


40

The various Celtic cultures fit pretty much all of your Orc needs. More specifically the Gallic tribes which had mostly been dispersed/assimilated by the 3-5th century CE under Roman rule. ✓ Big and value strength: See Brennus above. Just look at that mustache. ✓ Their society is tribal, with a war chief: The general social structure was tribal, led by a ...


37

Cure for cancer, Alzheimer's and heart disease These three are the big natural killers. Cheap, clean, ubiquitous and plentiful energy sources Air pollution is the biggest non-natural killer. The biggest source of air pollution is the burning of fossil fuels and biomass. If for instance Polywell nuclear fusion turns out to work, then we can remove ...


28

While there are already some good answers, it should be noted that for exampled Germany, South Korea and Japan are not economic superpowers, but mere great powers. (Germany and Japan lost political power for historical reasons and held back) I think a better example could be the European Union. definitely a large economic power politically weak due to ...


26

Limit the availability of raw materials, in particular fossil fuels and iron. Without fossil fuels you are limited to wood burning as a power source which is far less energy dense and a much more finite supply. Without iron it's much harder to make much of the earlier engineering feats. This means you don't get useful steam engines or railways which were ...


24

It's a terrible defensive structure. Once you're close enough to the walls, you've eliminated flanking fire coming from the towers because the walls themselves block line of sight. This would allow anyone getting close to the wall to be safe from attack (except from directly above), giving them plenty of time to muck around to breach. Were they willing to ...


24

With the advent of genetic engineering First a bit of background... Two of each "kind" Young Earth Creationists concede that — no — Noah did not bring two of each species because it is simply not physically possible to squeeze that many animals into a ship of the dimensions given in the bible. Instead Noah brought two of each "kind", where a "kind" is a ...


22

Both Iceland and Easter Island were deforested by people who settled there. The Vikings let their farm animals loose and they probably used a fair bit of wood for keeping warm, boats, huts and metallurgy. The combination left the Island deforested. What happened on Easter Island is less clear but similar result. Whether such an outcome is likely over ...


22

The limit will be when poop is high enough that people cannot dig through it to get to food. They can dump poop into ocean or rivers, but that leads us to second limit: They eat away dry land (till they can no longer dig from the bottom), so time to starvation depends on size of the continent you are on. Technology could help dig deeper, or move to a ...


22

Yes it could The Wikipedia article on the subject is quite detailed and offers the exact answer to your question. The L4 and L5 points are stable provided that the mass of the primary body (e.g. the Earth) is at least 25 times the mass of the secondary body (e.g. the Moon). The Earth is over 81 times the mass of the Moon (the Moon is 1.23% of the mass of ...


21

Tolkien's Orcs were based on the Mongol conquests. So, to keep his tradition, I'd choose the Scythians (9th century BC-4th century AD) Scythian women trained with the bow and they fought along men, to the point they are one of the sources for the legends of the Amazons. Their women might have even worn trousers while riding according to some burial sites. ...


18

You're positing a world that has no surface plants. That's... implausible. There are plants out there that can manage climatic extremes far worse than anything humans could live through. Plants actively thrive in concentrations of CO2 that humans would find lethal. You might easily have a massive die-off as climate change modified local conditions, but ...


17

No, it’s not within our power to kill all the deep sea fish within a year. Vertebrates that we kill higher up in the ocean will just fall to the sea bed and become food for them. And even if we could stop any organic matter from falling to the ocean floor, some vertebrates would still survive around geothermal vents.


16

They already are. And that includes us humans. You just can't see it. Our patterns are called Blaschko's lines. They exist because when we are embryos, the cells that will form our skin migrate in waves to where they will be. In almost every human the cells are all genetically identical, but if some of the first cells mutate, or in the case of chimeric ...


15

China Napoleon Bonaparte is supposed to have said “Let China sleep, for when she wakes she will shake the world.” Known for years as the sleeping tiger, we've recently seen China take a more active role on the world political stage. The words of Bonaparte show that China has had the potential to exert its power on the world for some considerable time, ...


15

Science doesn't really "prove" anything beyond a shadow of a doubt. It does, however, find different things that confirm that same hypothesis, each one contributing to making it far more certain than it was before, without ever reaching 100%. Myths. We'd probably have consistent flood stories from Peru to Siberia, rather than just from the Hebrews, ...


15

Nightsky cooling will be important. The sky is cold. Even with a full atmosphere in the way, it can act as though it is -50F. With no atmosphere, it can get down to almost 0K. That lets you radiate a lot of heat! Clearly the only source of heat or UV radiation or whatnot is the sun, which we know orbits closer to the center of the flat earth, so there ...


15

That is far too advanced to expect technology to remain static for long. Technology advances without new resources - new resources certainly shape how technology advances, but better methods and processes develop using the same resource constraints. Coal is not the cause of industrialization, so eliminating it will not prevent advancement. This may be ...


14

A plausible reason would be a Near Death Experience, for the country itself, such that secret negotiations and the corruption that naturally goes with it destroyed them economically and caused a major coup attempt that nearly turned them into a dictatorship. In the shooting war that followed to prevent this political disaster on top of an already devastating ...


14

Oil Eating Bacteria might work. The BP oil spill was cleaned up in part by using oil eating bacteria. In your world, have a species of bacteria that will ravenously consume petroleum, thereby making crude oil non-existant. Here is some maybe potential problems. You will need lubricants. Oil isn't exclusive, but it's easy enough to get. Before you go to ...


14

By way of water. To get a flying tetrapod you need a predecessor that can spare two limbs from full time locomotion such that they can differentiate into wings. The ancestors of birds are thought to have been semibipedal and semiarboreal - they could run on their back legs which opened the possibility of differentiation of the forelimbs into appendages ...


13

There is in fact a relationship between a planet's distance from its star and its orbital period. This is known as Kepler's Third Law. Mathematically, this can be formulated as: $$ \frac{P^2}{a^3} = \frac{4\pi^2}{G(M+m)}\approx\frac{4\pi^2}{GM} $$ Here, $P$ is the period, $a$ is the semi-major axis (distance), $M$ is the star's mass, and $m$ is the ...


13

They could do it the same way we are doing it today, by burning large quantities of stored fossil fuel, releasing large amounts of Carbon Dioxide into the atmosphere. Based on the low population numbers burning them for semi useful purposes are out. Also due to the low technology they are going to be limited to near surface deposits. The most likely ...


13

The surface conditions you're describing are closer to an ice age than any other situation. In practice the ice caps covered only 35% of the land mass, though they locked up the vast majority of the fresh water. This means that the ice age was one of the driest periods in the planet's history. The more of the water that's locked up in the poles the drier ...


12

Snowball Earth https://252mya.com/products/snowball-earth-wallpaper The Snowball Earth hypothesis proposes that for a period during the Precambrian, the Earth froze over entirely or almost entirely. https://en.wikipedia.org/wiki/Snowball_Earth The Snowball Earth hypothesis proposes that Earth surface's became entirely or nearly entirely frozen at ...


12

Gamma ray shower from a close-by supernova. The explosion of a supernova close (few tens of light year) to the Sun would bathe the Solar System in a shower of highly energetic gamma rays, which are lethal for life. Moreover, stripping over the ozone layer, it will allow also radiation from the Sun (UV, X-ray, gamma ray) to easily reach the surface. Being ...


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