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In the far future the posthuman successors of mankind have disassembled the stars and live on ultra slow and ultra efficient solar system sized computers, Matrioshka Brains. The last enemy of intel...
In my world, physics works exactly like on Earth, except that there is a narrow, 400 foot tall magical column sticking vertically out of the ground, which is magically always extremely cold -- I'm ...
How much force/energy is required to punch someone so hard that the person is sent flying at the speed of sound? Also, what can you compare the force/energy to? For example, is it comparable to a ...
I have a story in which a King, knowing his kingdom will fall, would like to have a scorched earth policy. The King would order all residents to begin salting the earth to ensure nothing there can ...
I'm currently outlining my science fiction novel which deals with humanity reaching Type 3 civilization status. My goal is to place an emphasis on hard science fiction while featuring fantastic tec...
How small could our Sun be and still "burn" with nuclear fusion and emit the same spectrum of light and other radiation as the real Sun does? Edit: The goal is to have a small sun inside a huge v...
On earth there can be hours where the moon is up during the same time the sun is in the sky (daytime moon) due to the combined rotation of earth and orbit of the moon. I would like to have an earth...
My question is pretty basic, would square thrusters and RCS ports have any real drawbacks over round ones? I know that angles on windows for airplanes is a problem because of the pressure, so I don...
I'm working on a computer program which generates realistic planets for worldbuilding purposes. I've run into an issue with calculating my planets heat loss. While radiogenic and tidal heat generat...
How would I calculate if it is possible to have an eccentric enough orbit around a gas giant to dip the periapsis some depth(how deep?) into the atmosphere of a gas giant like Jupiter or Saturn and...
Summary The main idea behind the "cuboverse" is that spacetime distances are measured by (something close to) the sup norm or infinity norm. Under this norm, spheres (the set of points at a fixed ...
Most works of fiction have quite imaginative views of time travel. Mighty machines that teleport in time instead of space. Gaping portals in space that take you to another time. Mystical beings wit...
It has been determined by observation of the stars that the gravity on Flat Earth is due to it accelerating upwards at 1G. This is what holds people and objects to the surface. It has also been det...
Considering the well-established relationships between stellar mass, surface temp, and luminosity, how unusual would it be to find a star (or brown dwarf) that possesses about half the mass of an a...
I seek to build a habitable moon of a giant planet, thus I looked at the Rouche Limit Equation to figure out how to get the biggest possible Hill Sphere for my moon to exist in. $r_H = a(1-e)\sqrt...
I'm referring to an entomological plastron which is a structure that traps a bubble of air next to the insect's body but permits contact between the air and the water. As the insect consumes oxygen...
I'm writing a cyberpunk novel where one of the characters has an augmentation that allows them to echolocate. The idea is that there is a device on the center of his forehead (is there a more opti...
I've looked around the forum but didn't find an answer to this particular question. In short, what food could realistically be produced in a space station assuming current (or near future) technolo...
What kind of technology would be required for a space travelling civilization to have an effective communication system or network that is similar in speed to the telegram? How would it work? This ...
AA (azidoazide azide) is a hyper-explosive 14 nitrogen molecule. My questions are: what are some theoretical ways to store it so it doesn't explode on you but on the enemy you throw it at, and what...
Rockets consume a lot of fuel and carry not eough payload. To reduce the fuel needed, why not send it in the mesosphere? Imagine a big balloon, capable of carrying a small rocket to the mesosphere...
I'm writing a rough sketch for a book about a world where people sorta violently and suddenly get barely working superpowers. That is every time each person uses their power they run the risk of ki...
I'm sure most worldbuilders will have heard the aphorism that in space "Everyone sees Everything", or that "There Ain't No Stealth In Space". I'd like to propose a possible solution to this. Th...
From time to time I'll see things talking about how thanks to all of our radio communications, we're effectively broadcasting our existence to the entire universe. However, when I did some back-of-...
I was reading this article from NASA about chemical rockets and they argue that, with a planet 50% larger than the Earth (assuming similar density, about 1.5G surface gravity), it would be impossib...
I am dealing with a dystopian story that tries to come up with some kind of total surveillence or control from higher authorities. The authorities threaten to kill those who disobey them by simply...
Prior to the Cambrian, there have been three separate ice ages--the Huronian, from 2.4 to 2.1 billion years ago; and the two Cryogenian ice ages, from 720 to 635 million years ago, split in such by...
An interstellar traveller stands upon the surface of an alien planet beneath the light of an unfamiliar sun. The planet upon which he stands orbits one star of a binary system in which one is a G-c...
The Karman Line is one of the most commonly-used definitions of the "edge of space". As an airplane flies higher in the atmosphere, the air gets thinner and thus the lift decreases. This can be c...
For my hard sci-fi story, I would like to have a planet similar to Titan (very cold, nitrogen atmosphere, methane seas) but with a surface gravity in the region of 1g. Could this occur, or would th...
In my earlier question, regarding airships, I mentioned fictional gas, as light as hydrogen but non-flammable. Is it possible to make chemical element, with atoms made not from nucleons, but with s...
Everybody has seen superpowers like superstrength, flying, and regeneration. While flying and superstrength are quite straightforward regarding the energy cost, regeneration is not. In this questi...
This question draws on an old idea but it is different. The original question is, "If everyone in the world jumps at the same time, will the Earth move?" My question is,"If everyone in one hemis...
Premise In this Earth-like world, a multi-billion dollar privately owned aerospace/defense corporation is devising a secret plan to manufacture a fleet of nano-bots. These nano-bot have swarm inte...
I want to popularize the following or a similar belief. In many thousand years people will travel back in time to give us an afterlife, if we make it possible, by going the steps, that will lea...
How can I predict the color of the sky based on the information provided? Atmospheric composition: | 2% Trace gases | 58% Nitrogen | 26% Oxygen | 11% Argon | 3% Carbon dioxide | Average s...
I have a planetary system in which there is a huge planet and a moon orbiting it which has an atmosphere and water (and actually everything needed to sustain life). Thing is that I'm sure the mass...
How do I calculate the thickness of the upper ice layer on cold ocean worlds like Europa, Enceladus, and Ganymede? I'm asking this for a programm I'm currently writing. The given/known quantities ...
For the purpose of this post, full spectrum means a non-trivial number of frequencies within a non-trivial band. So human eyes aren't full spectrum within the visual range (each cone is wide band, ...
There are several previous questions concerning concentric shells. I won't reference them here because this is different. I understand that there is no gravitational effect inside a concentric she...
I was curious about an odd effect I first saw in video here: YouTube : Copper's Surprising Reaction to Strong Magnets In the video, a big heavy magnet is brought to an abrupt halt by a simple piec...
What would be the diameter and rotational speed of an O'Neill cylinder on the inside surface of which centrifugal and coriolis forces are equal to "gravity" and coriolis force on the surface of Ear...
Pathogen Note: For the purpose of this question I define a pathogen to include viruses and/or bacteria. Edit: I don't exclude other biological agents such as fungi that might have the same effect...
Little side project on fantasy story with dragons (or wyverns to be exact, but they're equivalent for the purpose). I have dragons roaming the country side, laying waste and ruin in their wake. As...
I was having fun reading this article about making cement on the moon when I asked myself (and now you), is it possible to make a suitably high-compressive-strength cement on Mars? Since concrete...
I'm looking to create a species of marsupial that is heavily K select, which is to say they put significant effort into raising their young after birth (both of them :P ) in which both the male and...
Background: The moon has been selected as the base for human space exploration. Rather than ship tonnes of material out of earth's gravity well, interplanetary spacecraft and space stations will be...
In a very distant future people have survived by slowing the metabolism to extremely long timescales, reducing the energy consumption per time. It is causing thought processes and movements to be e...
So in this world somewhere in distant future. The government has created I.D Chips that are designed to be biologically implanted into its own citizens. To ensure extra "security" and also act as a...
This is a purely hypothetical question but I can't find a satisfactory answer to it. Let's say somehow Jupiter collects enough mass to be considered a brown dwarf. Let's assume Jupiter achieves a...
