# All Questions

20,984 questions
21answers
10k views

### What would be best way to re-melt Mars' mantle and core to revive its magnetosphere

Missing magnetosphere on Mars keeps popping up. Most likely caused by Mars core being cold, mantle not bubbly enough. Mars mantle is dormant, core does not move. What would be good way to get it ...
8answers
1k views

### How can a world with constantly-moving nomads form?

I've been working on a world for a game I'm making. The basis of the game is that you have to carefully manage your resources, and to keep moving. I'd like to build a world which fits that. These are ...
5answers
4k views

### How would a civilization that has been living on a “cube” Earth differ from one on a “spherical” Earth?

Another question based off of this one here. Let's say on a cube styled Earth-like planet, there was a similar race to humans. If the differences in the planets were minimal (besides, you know, the ...
0answers
291 views

### Might non-organic beings exist on an actual planet, as opposed to a moon? [closed]

In the past two years quite a few metallic objects have been observed leaving the dual planet system third from the Sun, such as that pictured here: As is well known, the smaller of the dual planet ...
2answers
2k views

### Are planets in the same altitude level? [closed]

Maybe this has been asked with another name, but I didn't find it. 1) Are planets in the same altitude level? 2) What defines altitude in the space (universe)? 3) Is the universe a XYZ plane? 4) ...
4answers
802 views

### What would happen if you attach 2 huge ion engines on the north and south side of planet earth?

I was wondering what would happen if you attach 2 Huge ion engines(I mean really really really huge) to planet earth. They should be attached on the north and south poles. Are 2 huge ion engines ...
1answer
272 views

### Volcano the size of Australia

What would happen a volcano the size of Australia were to erupt? How high on the extinction-list would it rank? Would it be above the asteroid that hit Earth and killed the dinosaurs? Which known ...
7answers
2k views

### An interplanetary coordinate system

On earth, we use a simple but effective coordinate system which determines position unambiguously on the surface (GPS achieving accuracy within 1 meter, which speaking as an engineer, is a remarkable ...
5answers
2k views

### How would todays (handheld) guns/ammo evolve in the far future?

If mankind in ~ 1000 years would still use chemical propellants for handheld weapons and their ammunition, how would they improve, given the following: There has been no dark age, but constant ...
9answers
6k views

### What size asteroid is needed to move the Sun?

What kind of asteroid does it take to hit our sun out of its current position, even by just 50 meters? And which size does it need to have in order for it to do so? Would it continue to travel ...
2answers
281 views

### Can two persons have a common consciousness?

Let us consider two persons who can feel what the other senses and know what the other thinks. Now do these two persons have a common or single consciousness?If so,will it do good, if we succeed to ...
3answers
1k views

### Can a planet with no tectonic plates technically exist and be habitable?

Going off of my other question here, I guessed that a cube planet could work out. BUT, would it be possible for the planet to exist and function as a (relatively) normal planet with life on it without ...
8answers
2k views

### How to make a world MAD

I have been reading about mutual assured destruction and deterrence theory on Wikipedia, and it got me thinking. What would it take for some of the countries in the world to actually destroy one ...
11answers
21k views

### Can a nonspherical planet exist and can it be habitable?

In both fiction and non-fiction worlds, that attempt to keep a sense of realism, planets are spherical. Is it possible for a planet to not be shaped like a sphere? If such a planet is possible ...
12answers
9k views

### Can planets die of old age

I was wondering if planets die after a certain amount of time, perhaps because of decay? If this is the case, how do they die and how long does it take? Do they implode? Explode or perhaps just fall ...
8answers
1k views

### How could a human learn to talk to “apes” (like from Planet of the Apes)?

The movie Planet of the Apes shows (and in the end explains away) humans talking with the apes in English. Assume we don't want that plot point but the setting is similar otherwise: The human is a ...
2answers
778 views

### How fast must a planet with 1.27g spin to allow for space elevators?

Obviously the greater a planet's gravity, the stronger the material of the space elevator's cable would need to be in order to support its own weight. However, doesn't greater rotation speed reduce an ...
3answers
748 views

### A species without pain

In my current setting, one of the main dominant species' is the Golem, former automatons made of assorted materials who gained sentience through some kind of life-giving explosion. As such, though ...
1answer
535 views

### How could you build a universe [closed]

EDIT : I made significant changes to the question which is by its nature open. Dark energy and its repulsive energy that expanded space at its origin was decisive in creating the playground for the ...
3answers
268 views

### Evolution into sentience

Given a world where a sentient species already populates, how would the population respond to another, unrelated species evolving into sentience? I think this can be effectively split into 3: Its ...
10answers
4k views

### What would a Martian calendar look like?

On Earth, the mostly used calendar is the Gregorian calendar. This calendar has many issues though, just to list some: It is not perennial. Each year starts on a different day of the week and ...
4answers
4k views

### How big would a “Ring World” have to be to orbit a black hole?

In many Science Fiction books and games, there are worlds or planet-like objects that are rings that orbit (or float around in space) (some examples being the Halo (from Halo) or the Ringworld (from ...
6answers
3k views

### Sapience Pulsar - Could Intelligence Come in Waves?

So imagine this scenario: Sapience (which I define as Human-like intelligence or better) is a relatively common occurence once a life-form is on a specific brain-arms-race path like Hominins have ...
3answers
4k views

### Are moons always the same colour?

When viewed from their planet, are moons always the same colour as ours? Or is there a variation? What other colours might be possible and what causes the differences in colour?
3answers
2k views

### How long would a planet take to recover from a large asteroid impact?

As part of my world's planetary history, an asteroid impact has delivered a sizable quantity of a previously unknown metal to the planet Earth. By sizable I mean a deposit large enough to sustain a ...
9answers
27k views

### Designing a map for a fictional city

I am in the process of beginning to write a fictional book. The book will be set on present day Earth however I want there to be a fictional city. In my head, I have decided the name, that there ...
8answers
409 views

### Arctic Airships, Part 2 - Navigation

This is the second question in my Arctic Airships series of questions. The first one is Arctic Airships, Part 1 - Generating Electricity. The setting is outlined in Part 1, but I'll rehash the ...
8answers
832 views

### Buying energy from the sun?

How could an organization force solar energy to be bought from them? Something like: A large structure (in space presumably) fully/partly blocks sunlight reaching Earth, so anyone here wishing to ...
7answers
1k views

### Does an expansionist, monotheistic religion require a central prophetic figure?

This question builds on these previous questions: What common structures and systems exist in global organized religions? How to explain the co-existence of peace and violence in religion I am ...
3answers
4k views

### How to fight an Eldritch Abomination

The Situation The fantasy world of Terrearth is once again threatened by the Shadow, a sentient, but completely unintelligible being composed of Absolute Evil, whose sole purpose is to destroy the ...
9answers
4k views

### What are the possibilities of a dwarf planet orbiting opposite Earth's orbit?

I am drafting a short story about a small object orbiting the Sun at the precise 'speed' as Earth's opposite the Sun, undiscovered by us due to its position. The problems I see with this include the ...
3answers
1k views

### The practicality of mail armor cloaks

Somewhat related to my previous question, How to make a realistic giant, since it has been established that a nine- to ten- foot tall humanoid would be quite a bit stronger than a normal human, I was ...
5answers
1k views

### Arctic Airships, Part 1 - Generating Electricity

This is the first question in my Arctic Airships series of questions. The second one is Arctic Airships, Part 2 - Navigation. The premise: An Earth-like planet plunged into an ice age roughly 2,000 ...
4answers
1k views

### Classifying possible sources of supernatural abilities in a simulated universe

Let's assume that the world is a (rather crude, video-game-like) simulation and that each sentient being is just a program running in the system. The universe resembles our own on the macroscopic ...
6answers
1k views

### Matrioshka Testing: A way to keep your AI honest (or at least guessing)

I have had some time to ponder my previous question, and here's what I came up with. You take your freshly baked AI (or your destructively uploaded human), and put it in a box$^1$. As far as it can ...
13answers
7k views

### How close can we get to heated blades?

In many sci-fi scenarii, most often when mechs are involved, it is not uncommon to see such a technology, usually called heated blade. Supposedly, it would make the blade even more efficient at ...
6answers
499 views

### Cheaper to grow crops in Earth and sending it to space or to grow them in orbit?

I'm interested in knowing if in terms of cost/efficiency/quality would be better to grow crops(food) in Earth and then sending it to space habitats on orbit, or would it be better to grow them in ...
7answers
3k views

### Brown Dwarves: Dyson Spheres in disguise?

Would a Dyson sphere make a red dwarf appear to be a Brown Dwarf? Would it disguise a star enough to misidentify it what size it is? I'm just wondering if it could be possible that some Dyson ...
14answers
4k views

### How to avert AI. as a main player in the future?

it's me again :) With the help of the fine people of this place I have been able to find solution for a number of problems and come up with compelling technologies. One question keep bugging me, ...
6answers
1k views

### How to avoid 'Geary-Syndrome' at relativistic speeds (in space)?

Hello again :) My first questions had some wonderful answers, but brought me to the following problem: Although (in my eyes) really dull, the Cpt. Geary series (the Lost Fleet) tends to depict the ...
4answers
345 views

### Is there a way to simulate the arrow-resistance displayed by heroic characters in fiction solely through biological traits?

Exactly as asked on the title, is there a way that a human, or at least, a species that appears outwardly human, could survive being pincushioned by arrows, at least for a suitably dramatic length of ...
4answers
7k views

### How to make a realistic 'giant'

Imagine a race of what we would call 'giants', each of them possibly around 8 to 10 feet (2.40-3.00 meters) tall. What differences would they need compared to us regular humans in order to function? I ...
5answers
914 views

### Which space-based weapon technologies are going to thrive?

Given enough time for research (centuries, basically in a post-faster-than-light-era) and resources, which current (or new) weapon technologies have the most potential? Missiles? What payload would ...
7answers
1k views

### Could a non-material living being exist?

I'm imagining an electromagnetic wave that could deliberately alter its wavelength. It would be a totally unfamiliar type of creature, but actually, we material beings act because of the electical ...
2answers
193 views

### How well could we counter global cooling?

The earth is migrating, somehow (it doesn't matter how, but it's not directly destructive) into a higher orbit over the course of a century. Details: The earth-sun distance will increase by 150,000 ...
6answers
6k views

### What could cause Earth to slowly fall out of orbit?

I would like to have Earth slowly move away from the sun, taking somewhere between several months and a couple of years to reach the point where human life on the surface is no longer possible. (The ...
2answers
559 views

### Could a non-relativistic universe be logically consistent?

As I understand it, the principle of relativity was accepted from Galileo until Maxwell, whereupon the equations which predict constant speed of light imply a preferred reference frame in a Euclidian ...
2answers
306 views

### How long to freeze a planet?

If some advanced race were to make a solid opaque shell around our Sun, say around Mercury's orbit, something like a Dyson Sphere, how long would it take for Earth to freeze over and end most life?
6answers
2k views

### Energy source for a generation ship

A generation ship was sent out a long time ago, to colonize a far away planet. However the ship failed to reach its goal due to navigational issues (which also means they didn't have any clue where in ...
6answers
1k views

### How would society be different in a world where sex/gender is trivially changable?

Similar to this question, but with major differences. The set-up is that past-humans implemented, through biological engineering, the ability to switch between male and female in everybody. However, ...

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