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I was in the shower the other day thinking about the sun going Nova, you know...like you do, and a thought occurred to me: Could you turn the sun into a stable, mostly closed system? Some detai...
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...
In another question Everybody has a brain implant. What measures can a criminal take to escape justice? I assumed that a brain implant would be possible in the future for surveillance. In this que...
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...
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...
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 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...
EDIT Why this is a world-building query. If I had framed this as, "In my world where magic requires the expenditure of energy, a powerful wizard decides to open a path through a large lake,etc. Th...
Now that FTL travel is here there are all sorts of family outings we can go on. One of these is a scale model solar system lovingly made by hobbyist Barty Slartfast. In full scale Sedna is thre...
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...
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...
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...
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...
Assuming that the only fancy available technology is FTL drives (to get there) plus anything needed to protect and sustain a crew during the journey from Earth to Sagittarius A (whether it takes a ...
Suppose you could pump a load of energy into an asteroid at a safe distance. As energy gets added to the object, does it make sense that this could be done in a way to get the asteroid to different...
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...
So my story is set in the TRAPPIST-1-system and a rogue planet enters the system. When it's still far off, a scientist discovers that one of the numbers is slightly off. (She has some tables that p...
In my fiction I'm setting up a civilization which uses Laser Propulsion for moving things between bodies within a solar system (assume Earth/sun analogy). Laser Units have been set up anchored to a...
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...
In my story a man who works in Military Intel gets early warning that a nuclear attack on his base is inbound. He abandons his post, grabs his wife and kid from on base housing, and books it out of...
I'm making a mostly ice planet with two moons. For the purposes of this question, let's assume that they are both proportional size and distance to the size and distance to our moon. Both are tidal...
Suppose that there is an alien spacecraft travelling towards the Sun. This spacecraft is similar in design, size and power output to Voyager 1 and Voyager 2 as they were immediately after launch fr...
I ran a quick calculation, and the mass of iron required to form a black hole is on the order of 10^40kg. So, suppose that in my story there is this almost much iron available to somehow be brough...
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...
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...
I have a region on a planet with identical parameters to Earth but different landmasses that is rather similar to the southern ocean on Earth. There is a single piece of land around the size of th...
I know that in the past I posted questions on if specific bodies larger than the moon--Mars in one and Titan in another--but this series deals with questions regarding Earth's effects by a natural ...
Motivation The Square-Cube law is usually cited where questions of scale arise. Actually applying it to real-world objects quickly shows that it is completely unusable to approximate weight differ...
I know that objects with lower mass tends to orbit objects with higher mass, is it possible to have a Moon sized planet who's mass is so heavy that an Earth sized planet orbit it as it's Moon in a ...
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-...
Back home, Earth had gone through an impact-coalesce cycle only once. Since then, its core has been 84% iron, 6% nickel and the rest being labeled by The Encyclopedia of Earth: A Complete Visual ...
I'm working on a story involving first contact with an alien species that bases their space travel on directly manipulating gravity fields. My question is not about how that would work, but rather ...
If I push a couple of magnetic asteroids into mars gravitational field, could they form an interlocking series of magnetic fields able to protect mars from solar winds? Size limits for asteroids ...
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...
So for lack of a better term (I'm sure there is a better term) imagine a universe without curvature as being like a sheet of paper. You have left, right, forwards, backwards, up, and down. Now take...
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 ...
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...
I'm playing around with a story idea that includes vacuum dwelling intelligent life, but I'm not sure I understand the constraints of biochemistry I need to deal with. There's lots of potential s...
A common, matter-efficient science-fiction habitat is a hollow cylinder or ring in space that is spun to simulate the pull of gravity on its interior surface. These habitats have been imagined as s...
The last time I asked a worldbuilding extinction question, I asked on what sorts of factors would create an extinction event in which 96% of all terrestrial species and only 70% of marine species d...
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 ...
A XX century researcher time traveled back into the prehistory. He is not in danger of death or anything, but he has only energy to attempt one jump. He must jump back during the sunrise either i...
A common, matter-efficient science-fiction habitat is a hollow cylinder or ring in space that is spun to simulate the pull of gravity on its interior surface. These habitats have been imagined as 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...
In a world set many years (At least a generation or two) after a near extinction level nuclear event, how could a recovering population set up a internet or internet like service? Key points I'm i...
What amount of energy would you need to expend to create an arm out of nothing but energy? Of course we have $E = m c^2$ telling us the energy any amount of mass represents. Given the average of a...
I want a planet that is twice the diameter of earth's but has very similar gravity, atmosphere, and day length. Would doubling the rotational speed of the planet meet these parameters without notab...
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...
Could a planet support both large mammalian megafauna and non-avian dinosaurs at the same time? My worry is that bigger mammals have progressively more trouble with dissipating body heat, whereas ...
