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I'm spitballing a story where the main character goes through a monstrous transformation. Part of the conceit / my enjoyment is that she's an oncology researcher and will be tracking the transform...
Do {any, some, all} {unicellular, multicellular} plants require free oxygen? For example, would a cabbage asphyxiate over night, or even in daylight, in an oxygen-free atmosphere?
A young B-type star (with a mass of about 10 M$_{\odot}$) is surrounded by a debris disk extending from about 2 AU to 1000 AU away. The disk has a mass of about 300 Earth masses - enough to form qu...
Can electricity be generated directly from nuclear decay? It occurred to me that in alpha decay two protons fly off rapidly, leaving their associated electrons behind. If the alpha particle was ca...
Could nuclear energy be a basis for energy storage with foreseeable technology? One approach would be to use excited nuclear states, but I suspect they would be too unstable to ever be useful. Al...
When water is electrolysed with graphite electrodes some of the oxygen reacts immediately with the anode to produce carbon dioxide. Does a similar reaction ever occur at the cathode, producing meth...
Quantum Computers are considered a more powerful type of computer than so called 'classical' computers. While a typical classical computer could be considered as a black box that can solve Polynomi...
In my story, I have a small extended family of 30 to 40 individuals ranging in age from 0 to 50 who are on the run from Chinese and Japanese forces in 1400AD. No place in Asia is safe for them. By...
This is a multi-species animal army with predators of all shapes and sixes, foxes, lions, bears, tigers, leopards, wolves, lynx, eagles, falcons and so on. The herbivores have been excluded from t...
The Milky Way and Andromeda will collide a few billion years in the future. Stellar collisions will be rare because - as Douglas Adams put it - "Space is big. Really, really big." In the galactic d...
One of the cool things about the Moon is that the far side has a thicker crust that the near side.1 One theory explaining this is that the Moon was hit by an object, possibly a moonlet created by t...
The known charge-conserving decay modes of free neutrons all involve the production of a proton, an electron and an electron antineutrino: $$n\to p^++e^-+\bar{\nu}_{e}$$ This beta decay is why, out...
I've had a number of interesting conversations with people about how the cosmic microwave background (CMB) will evolve in the future. The CMB is the sea of photons left over from the epoch of recom...
Often, when I'm building a world, I want to start out by determining some of its key properties. Maybe I'm trying to calculate a habitable zone, or figure out how long a year would be on a particul...
Introduction In our universe, the cosmic microwave background was formed approximately 400,000 years after the Big Bang. It was hot, but within a few million years after the Big Bang, it would no ...
The Sun has nowhere near enough mass to enter the branch of stellar evolution that would lead to a supernova, fortunately for us. However, there are planets that orbit stars that are destined to go...
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...
A fictional starship that I am designing functions via a form of Bussard ramjet that uses hydrogen from the interstellar medium as reaction mass, not as fuel. In order to accelerate the propellant...
Human physiology is adapted for life at 1G, but planets colonised by future humans will likely have different surface gravities. What is the range of values for surface gravity that humans can com...
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...
This question is a sort of follow-up to Samuel's previous world map question, Creating a realistic world(s) map - planetary systems. Lots of science fiction stories involve journeying to nearby st...
I'm working on a species of large bird, and trying to determine whether they will be able to fly or not. I know that this equation likely applies: $$ A = \cfrac{L}{\cfrac{1}{2} v^2 \rho C_L} $$ ...
Stars generate their energy by fusing lighter elements into heavier elements. The most common reaction in Sun-like stars is the conversion of hydrogen to helium via the proton-proton chain, but hea...
The question: What characteristics are necessary for a planet to be habitable for humans? What should the generic star and planet be like? The life forms are human, so they Need to have access ...
The question: What characteristics are necessary for a planet to be habitable for humans? What should the generic star and planet be like? The life forms are human, so they Need to have access ...
We are in a future where genetics has advanced to a point where arbitrary modifications can be done to living beings. Now a geneticist wants to make a flying human. That is, he wants to modify a hu...
A key part of the plot in a story I'm working on revolves around the main region being on top of volcano that is set to erupt. The trouble is that the region in question in my setting is roughly th...
It is some small number of years into the future. We are regularly using beamed energy, as defined in this answer: large arrays of microwave transmitters. We have developed this so that these array...
The idea of uploading one's personality and consciousness to a computer is a semi-common science fiction trope. It has been suggested as a way to essential immortality. In a story I'm working on, ...
The Technology We're in the year 2250 on an Earth-like planet. All the space on the earth's surface has been used up by the population of 15 billion, so we're moving into the air. Cities, along wi...
Effectively what the title says; What would different observers experience while travelling through / seeing one travel through the tube, and how could they be used to cut travel times? (Just answe...
So here is the situation. I have a character who is a trained modern gunsmith and he finds himself thrown into a setting where the most advanced firearm is the flintlock. I know some of the most a...
Suppose our alien neighbors woke up on the wrong side of the bed and decided humans would be less annoying if their home planet was hit with a giant artillery shell travelling at half the speed of ...
In 2015 we can rewind the TV, our CCTV footage and, if we wear an action cam, our latest adventure. However if we walk down the street and something happens we didn't quite catch, the annoying fact...
I am writing a setting for a role-playing game. In it an alchemist has finally found a way to create gold from lesser metals. Like his former historical models the alchemist is so jubilant over hi...
In this question I asked about the possibilities of what a boundary might be like, with emphasis on the storytelling. Now I'd like to investigate what a hard boundary would mean in quantum mechani...
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...
Inspired by many questions that make use of utility fog. Utility fogs are not, as the name might suggest, fogs, but rather lattice solids. Cells of the foam are pollen-like micrometer-scale mach...
The Solar System has entered a region of space where the laws of nature are slightly different. It will experience different physics for 3 years, then things will return to what we know now. Which...
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...
I want to send a flying saucer (a $\frac{1}{10}$ scale Independence Day City Destroyer - calculated as a sphere cap 112m high with 1.2km segment radius, $\rho$ about 43.3kg/m3) away from the sun as...
I'd like to be able to determine the appearance of the night sky from an Earth-like planet, in a solar system with multiple other planets, moons, and other bodies. Here on Earth, we can directly me...
For the purposes of my story, seen here someone who went through a similar procedure involving parallel dimensions (see here), becomes nearly indestructible , invulnerable to damage related to exce...
In many fantasy worlds, giants are as intelligent as human beings and others races that they either avoid stepping on or step on regularly. However, due to the square cube law, giants have a limit...
I am trying to understand if it would be possible for organisms to evolve by different means other than random mutations and natural selection. Eukaryotes were predicted to be formed by fusion with...
Due to reasons of magic an alien god that is about to takeover the earth in one year and can only be stopped by being shot through the entire earth. Assuming modern day Earth (no magic other then ...
I did some research recently for a story on the physical feasibility of some aspects of living in the Saturn cloud deck, and wanted to share it. Please, however, if you have alternate approaches,...
Sort of two questions here, but very related. One about whether a mammal-like animal could evolve to have a chitinous endoskeleton, I guess. Then a question of whether, if they grow horns, that ske...
I've been working on designing how an ammonia-ocean world might work and I've settled basically everything except one. I cannot for the life of me find any sources that actually provide a decent wa...
So the mass of air around the earth has doubled. How it doubled isn't part of the question, but for the curious let's say a space station floating around earth processed all the nitrogen, oxygen, c...
