Q&A with a focus on more stringent analysis. Questions and answers should be well-researched, clearly explained, and supported with references, equations, or empirical evidence based on current, widely-accepted science. Please read the category guidelines.
Filters (None)
I have seen a few similar questions but none seem to take the density of a planet into account. I'm creating a planet on which several small civilisations develop. The planet needs to have a few bi...
A terrible virus has made most of the populations and government officials of the largest superpowers on Earth stark, raving mad, without depriving them of their intelligence. They have decided t...
I have two planets that are the exact same size and mass of Earth. They orbit each other, and have an orbital period of one day. How far apart are they? The planets both orbit a star the same as t...
I wrote a novel based on a human civilization that lives floating cities and dirigibles on a small, atmosphere-abundant super-Earth with a liquid water core (there's a smaller solid core under that...
This question discusses what you'd look at from space, but mostly focuses on how you could identify the weather. This question discusses what resources a colony would need, but doesn't discuss ho...
I ask because I have a problem trying to find an appropriate launch window around that time or any point in the mid-1980s, and I need to reach Jupiter via Hohmann transfer so I can then use a serie...
I'd like to justify a lightning man in my world, and I have a theory that by some sort of magic, his cells in the dermis (middle layer of the skin - okay, for simplicity, don't count hair) are able...
This is an edit of a previous question. It has been edited so I can be more specific in my asking, as I'm still confused after looking at the answers to a similar question to my original. I have a...
Consider a civilization with the industrial age technologies. Oil and coal are rare (probably used up). All products produced by oil and coal are also nonexistent. The civilization has invented ele...
I know the innate contradiction present here: one cannot "prove" the supernatural exists, for a variety of reasons. But for the sake of argument I want you to consider this: A person is convinced...
I've mentioned in earlier posts that it will be much cheaper to build immense space-based observatory instruments than to even come close to launching an interstellar expedition. There are several...
Recently LIGO discovered gravitational waves caused by two black holes that were orbiting each other, and then collapsed into one black hole. A few months later, we find out that this actually happ...
In my fictional world I have selected all parameters to maximize the Hills Sphere of my planet. The planet has three times Earth's mass and it is located in 2 AU from its star that's 1.4 times more...
Could one (and how much) generate electricity by building a wall connecting: South Africa to Antarctica South America to Antarctica Northern Canada to Northern Greenland Northern Greenland to Rus...
I have been looking at various animals that have evolved some level of aerial capability, and I came across Kuehneosauridae. Reptiles which evolved gliding struts, attached down their sides, which ...
Following on from this question: Can Cloud Nine be built? Let us assume we have constructed a Cloud Nine tensegrity sphere with a 2 kilometer diameter out of a durable material for use in Earth's ...
Earth, present time or very near future. Astronomers have just announced that it is believed that almost 9 billion habitable Earth-like planets exist in the Milky Way alone (this is true, but there...
Positive mass moves in the same direction as its momentum and if negative energy exists then it would move in the opposite direction from its momentum. I was thinking of a type of mass, known as "...
Basically, in the event of a blotting out of the sun á la an impact winter, what sort of food source (if any) could be used to sustain humanity? In my universe, underground/makeshift greenhouses ...
How dark would it be living in an impact winter? Where would an asteroid have to hit earth to cause an impact winter? gives a great breakdown of the effects of an impact winter, but I'd like to k...
For those unfamiliar, An impact winter is a hypothesized period of prolonged cold weather due to the impact of a large asteroid or comet on the Earth's surface. (Wikipedia) In my world I want...
Preamble The Alternity Cosmos II is a complement to a dice role-playing game that uses heuristics based on hard-science to 'build' plausible star systems for the Alternity game: http://www.altern...
Like it says on the tin. Problem? Basic configuration is not going to work. If I used several additional layers and all the Outer and Inner layers using carbon nanotubes, whereas the Middle Layer(s...
In this world a secret society "farms" people with desired features (personality appearances etc.). They have ectogenesis of course; but they can't afford personnel to take care of the "products" u...
Would that even be possible? Will the bones deform during early infancy? Will the cartilages between joints wear off faster? Will internal organs collapse under their own weight? I have no professi...
Well, gentlemen. Here is Part II. We know what to do about the manoeuvre, but we need to know possible tactical options the two Task Groups would use. Background Now, as previously specified, we...
When I was observing the Moon yesterday, I asked myself: What would happen if a meteoroid impacted the Moon on the more clear part of the Moon which we can see, leaving a crater of the size like t...
I have two earth clones, in essence, separated by *16550 miles (26350 kilometers). They are, of course, tidally locked, and orbit each other once every 24 hours. These planets orbit a sun identical...
Many authors describe worlds with higher gravity than our own, from whence super-muscular aliens originate. However, as we increased the size, mass and surface gravity of a world; there would be p...
Could an unmanned solar plane go not only above the clouds, but also so fast that it always is in the day-side of the planet? A solar plane flying above the clouds receives sunlight $12$ hours per...
So, after going through a some rough calculations, I figured my earlier question ran into a few problems regarding the final velocity of the asteroid. I pulled the mathematics a bit incorrect, so I...
So, I ran into a problem regarding the aftermath of a colonial war for independence. What happens is the following: The scenario is this: late 24th Century, humans have colonised the Inner Solar Sy...
My idea was to use 2 stages for an interstellar spacecraft (particularly the Orion Drive) and use it in a way similar to Project: Daedalus. Phase 1 would involve accelerating to cruising speed foll...
I'm not into psychology, but I've heard a lot about veterans who have committed suicide, went crazy, became addicted or have their lives ruined in other ways because of the shock they lived through...
Nobody knows where the big Blue is. Some people say it's a dream. Some people say it's the space between the worlds, where all the things that fall through the cracks end up. The occasional rains o...
Sometimes I reminisce about the giant eagles from The Lord of the Rings and two things come to mind: Boy, I wish I could have my own giant eagle! Could a bird even carry something that heavy on i...
Epimetheus is a planet with about three times the mass of Earth orbiting a sun-like star in the Andromeda galaxy. However, two major factors separate Epimetheus from Earth. First, it has a thick at...
Okay, so the heat death of the universe is approaching. You can't stop it. You can't dodge it. What do you do? You wait it out. According to wikipedia, about $10^{{10}^{56}}$ years after the heat ...
Think of a giant hemispherical shell, constructed of spaceships, sitting just far enough from Earth to be too far for Earth-based defences and close enough to effectively cast a shadow on the entir...
It is estimated that in about five billion years, our sun will enter its red giant stage. During that phase it will expand and completely engulf Mercury, Venus and possible Earth. Earth will either...
To start with, i know You measure the Kardashev scale from stellar success, but lets say we have a civilization that are vastly advanced compared to us, so they are equivalent to a type 2 civilizat...
Assume there's a human being who can keep a strong electric potential near to (or on) his skin. Is it possible to use the air-ionizing property, or similar ones solely or mostly solely based on thi...
In A World Out of Time, per Schlock Mercenary, Earth is moved to a new home by lighting a fusion candle. The fusion candle idea is discussed in the Schlock quote: Building a gas-giant colony s...
Cloud Nine is the name given by Buckminster Fuller to his proposed tensegrity sphere airborne habitats. The principle is simple and the physics seem to be sound. For a sphere, as its radius is ...
I have two earth clones, in essence, separated by 16550 miles (26350 kilometers). They are, of course, tidally locked, and orbit each other once every 24 hours. These planets orbit a sun identical ...
Useless Backstory "Why are you waking me up Sergeant? And why did we enter near-light speed?" "We received a distress call, and there wasn't enough time to notify you, sir." "What kind of distress...
Before we begin, this system is created by aliens, and all orbits are on the same plane. These orbits are similar to earth's in shape. So, none of this has to occur naturally it just has to be stab...
My basic question is could life 'as we know it' (carbon DNA/RNA based, using water as the main solvent in metabolic processes) evolve on a planet where the temperature ranges from 16 degrees Celsiu...
As per the title, given A billion ($10^9$) dollars. Present day technology. A year of time (including making projects and testing), (preferred, not compulsory) No restriction about maximal nor mi...
I have an engine with unlimited $\Delta v$. Don't ask how I got it, it's probably one of my earth changing inventions. Either way: I no longer like Earth and want to get off (I'm headed for a reti...
