Questions tagged [hard-science]

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Could a Luna-based colony successfully revolt against Earth? [closed]

Let’s say that a colony established by humans on Earth’s moon was, for whatever reason, entering a revolutionary war with Earth for its own long-term sovereignty as a planet/nation. Mars has also been ...
beeb8338's user avatar
5 votes
0 answers
88 views

What are the orbital perturbations needed to destabilize a system to the point of taking some bodies out of resonance and kicking out another?

I have a gas giant with a mass of $1.63314\times10^{27}kg$ and a radius of 66,559.052km and orbiting it are 4 moons. It orbits a star with 0.86M☉ at a distance of 5.03AU My question is what ...
Pointy Orb's user avatar
16 votes
3 answers
5k views

What is the largest fraction of Earth's sky that an astronomical object could take up (visually) before ripping Earth or itself apart?

I know the Roche limit limits how close another planet could get to Earth. Closer than that limit, and either it breaks apart or Earth breaks apart. I don't care what size it is, if it's a super-...
cowlinator's user avatar
  • 1,839
5 votes
6 answers
457 views

Global warming in an apocalyptic future?

In my world, there's a global apocalypse that wipes out humanity, but I'm wondering how global warming might continue even with the lack of additional greenhouse gases. If emissions suddenly stopped, ...
Papa Solen'ya's user avatar
7 votes
2 answers
519 views

How much better would metallic hydrogen be than conventional explosives?

How much more effective (if at all) would metallic hydrogen explosives be against armored targets? In this setting metallic hydrogen can be cheaply manufactured and contained in a metastable state ...
Vakus Drake's user avatar
  • 2,528
6 votes
1 answer
135 views

Readily available MIR refracting material

I am looking for a material that could serve to do the following: build a 5m x 5m wall that looks pretty normal (not necessarily during construction) but has the ability to transmit and refract MIR, ...
bukwyrm's user avatar
  • 5,859
3 votes
2 answers
118 views

How do I figure out where a moon is in the sky at a given time and place?

I use this planetarium tool to see the position of the Moon to check I have it in the right place for a given place and time, for my non-Earth plant. I'm considering having another moon. How would I ...
Syntal's user avatar
  • 53
2 votes
0 answers
74 views

Moving people and goods between spinning and non-spinning parts of a space station [closed]

I'm thinking of three possibilities - all of which have the user experience of elevators and don't require space suits. involves a programmed pod that moves a short distance in space between docking ...
dsanford0's user avatar
1 vote
2 answers
228 views

Building dams from underwater

A recent question of an underwater race hunting land-based creatures has been answered with "they can build dams" (here https://worldbuilding.stackexchange.com/a/253462/86466). I have ...
Vesper's user avatar
  • 7,407
1 vote
1 answer
191 views

How would sex chromosome inheritance work in a tetraploid trioecious species with the ZW sex determination system?

I imagined a trioecious angiosperm species descended from common cocoa trees (Theobroma cacao). Trioecious = three sexes (male, female, and simultaneous hermaphrodite). They use the ZW sex-...
mammifereviolet4694's user avatar
0 votes
1 answer
106 views

Questions about Pycocyanin [closed]

Okay, so I have been reading on phycocyanin for blue plants, for a spec bio project, and I have several questions. Which are all closely related in terms of how it functions.They are essentially all ...
DanceroftheStars's user avatar
6 votes
5 answers
1k views

Did I just discover that the ether that my etheric keels interact with is four-dimensional?

I have been working on deriving an answer to How should I determine the properties of keels and ether? myself, and I was looking at the lift equation: $$L = \frac{1}{2}\rho v^2SC_L$$ where: $L$ is ...
Monty Wild's user avatar
  • 60.3k
7 votes
1 answer
302 views

Can two species from the same genus but with a different sex determination system interbreed and have fertile (or at least sub-fertile) offspring?

In my futuristic world, there are two coelacanth species that are the daughter species from the famous West Indian Ocean coelacanth. One has the XY sex determination system (like humans, iguanas, ...
mammifereviolet4694's user avatar
5 votes
2 answers
274 views

On Habitable Moon Systems

Context I was working on a habitable gas giant moon, but I came across an issue in that, at the acceptable distances from its parent planet (10-20 planetary Radii, according to an Artefexian video on ...
DanceroftheStars's user avatar
0 votes
1 answer
215 views

If you Broke Mars' Perclorates and Benzenes How Much of an Atmosphere Would this Create?

Much of Mars is inimical to human life. While there are many problems I would like to focus on three: The low density atmosphere does not provide the pressure needed to sustain humans outside of a ...
Englishman Bob's user avatar
1 vote
5 answers
245 views

How would researchers on an alien planet be able to support their dietary requirements?

A group of scientists travels to a newly discovered planet shown to support life in the form of plants and animals. Obviously they can only bring so much food with them so at some point they would ...
PompousPamplemouse 's user avatar
13 votes
6 answers
8k views

If money were no object, is there an element or alloy that would make for better train tracks than common steel?

A question that arose from here. Say we have a planet with a different percentage of various elements than Earth, but steam train technology, and we were striving for train track longevity. Is there ...
Carduus's user avatar
  • 2,252
0 votes
2 answers
122 views

How could my organism lose most of its water?

I'm writing a short hard-science story about an organism that loses most of its water much like tardigrades before entering dormancy but this organism is the size of a cat, how could I explain this ...
Z Z's user avatar
  • 65
2 votes
1 answer
154 views

How much difference would Alpha Centauri A cause to the climate of a planet about Alpha Centauri B?

Imagine an earthlike planet in the habitable zone of Alpha Centauri B. Call it ACBc (although I am not sure ACBb has been confirmed). When ACA and ACB are closest to one another, they are about 11 AU ...
Mark Foskey's user avatar
  • 1,065
4 votes
2 answers
200 views

Solar Flare/CME Range Limits

The Setting: A binary solar system comprised of a KV-class Orange Dwarf, and an M-Class Red Dwarf which orbits roughly 600AU away. The Orange Dwarf has 4 planets orbiting around it, including one ...
Atlas the Worldbuilder's user avatar
6 votes
1 answer
164 views

How to calculate the expected rotational speed of a star

I am working on fictional stars, and I want to have as many points about them as I can, and most things I found relatively easy, except for rotational speed. I am not sure exactly how to find at what ...
DanceroftheStars's user avatar
8 votes
1 answer
428 views

Do Forbidden Lines in Stars Often Come in Groups

In previous questions, I asked about how a K2V star could develop an [O VII] forbidden line and how those x-rays would create "pseudo-aurorae". Now, I'd like to know if my star could ...
Neil Iyer's user avatar
  • 1,306
2 votes
1 answer
104 views

Finding a stable atmosphere for a different gravity

I am trying to find what would be a stable atmosphere for a planet, using this https://docs.google.com/spreadsheets/d/1cW7BIWlBUscqS9MVqs5gSbPH0OGzyE-j2cz6ADBSVzE/edit#gid=0 (you have to make a copy ...
DanceroftheStars's user avatar
3 votes
1 answer
267 views

Visibility of My "Psuedo-Aurorae"

I have been designing a habitable planet, its moon, and its star for a while now. Background My star is a K2V star with very strong solar wind and is about the age of the Sun. Every so often, when the ...
Neil Iyer's user avatar
  • 1,306
3 votes
1 answer
147 views

How could a K star develop an [O VII] Forbidden Line at 22.1 Å

The Goal I have been designing a planet for quite a while now, and I would like the star to have an [O VII] forbidden line in its atmosphere. There doesn't need to be too much, but I need enough for ...
Neil Iyer's user avatar
  • 1,306
6 votes
1 answer
3k views

How do human girls who are sterilised at age 9 develop as they mature?

On the world of Ruquelis, there are three genders, men, women, and lilim who are a female sex, with wings and clawed feet. Because of the genetics of this situation, lilim are less fertile and can ...
Monty Wild's user avatar
  • 60.3k
4 votes
2 answers
1k views

Amount of antimatter needed to propel large spacecraft?

Okay, So i'm not really into physics or mathematics but i'm trying my best to learn some bit of how the calculations needed for the amount of antimatter needed to propel a spacecrafft to relativistic ...
Ashimix's user avatar
  • 567
2 votes
1 answer
88 views

Exomoon Color as Viewed from Planet It Orbits

I have been designing a planet and it has one moon that is slightly smaller than ours. Just like how mars appears red and its dust is red, I realized that maybe if I altered the composition of my moon,...
Neil Iyer's user avatar
  • 1,306
1 vote
1 answer
205 views

How could a planet accumulate xenon in its atmosphere?

I am currently creating a planet with an atmosphere rich in noble gasses, especially neon, xenon, and argon. It's composition is roughly about this: Nitrogen (N2) - 61.5% Oxygen (O2) - 21% Neon (Ne) -...
Neil Iyer's user avatar
  • 1,306
5 votes
1 answer
333 views

Ammonia transporting blood

Okay essentially I am designing an alien ecosystem with an ammonia and methane based metabolism. Here's the formula for the metabolism animal analogs use on this planet: $$\ce{3CH2O + 4NH3 -> 3CH4 +...
Venik Hue's user avatar
  • 1,222
5 votes
2 answers
305 views

How deep underwater can red photosynthesis work?

The Setting: I have a binary star system. First star: K5.2V class Orange Dwarf, 60% the mass of Sol, 17% luminosity of Sol, and at 4.5 billion years old. This star is the only one with a planetary ...
Atlas the Worldbuilder's user avatar
3 votes
2 answers
155 views

Fire Analogue on Hydrogen Methane atmosphere Planet

Okay to summarize I have a planet with an approximate atmosphere of 44% nitrogen gas, 30% hydrogen gas, 23% methane and 3% other trace gases. I am working on an intelligent alien race on this planet ...
Venik Hue's user avatar
  • 1,222
2 votes
1 answer
193 views

Partially tidally locked planed due to elliptical orbit... Possible?

Would it be possible for a planet with an elliptical orbit to be tidally locked to a star, only for a certain part of it's orbit? If this is possible, then: could the tidally locked side vary from ...
Jacco's user avatar
  • 704
1 vote
3 answers
226 views

Would lenses work in a universe with four spatial dimensions?

Let us assume that we have a universe with four spatial dimensions rather than the three of our universe, in which matter can exist that is a four-dimensional analogue of three-dimensional matter. ...
Monty Wild's user avatar
  • 60.3k
7 votes
1 answer
439 views

Zero energy transfer between Earth and Moon with space elevators

I'm asking this out of curiosity, mostly as a response to Space elevator from Earth to Moon with multiple temporary anchors and some of the comments and answers there. Suppose you're able to build ...
N. Virgo's user avatar
  • 5,362
4 votes
2 answers
139 views

Trinary star system - Tidal locked planet [closed]

I'm trying to build a world where an earth-like planet is tidal locked to a sun in a three star system, where the other two would orbit each other in the center (being the central mass of the system). ...
Vitones's user avatar
  • 43
3 votes
2 answers
446 views

What kind of scanner can detect a hidden chip in someone's body?

So it's the lead-up to what might be World War III and the enemy is kidnapping and implanting mind-control chips into our people, one by one, to turn them into sleeper agents, to all attack en masse ...
Bigbio2002's user avatar
5 votes
4 answers
465 views

How small can a nuclear weapon get?

Context I am writing the section following a critical space battle where a rogue UNN Pearl of the Stars is taken down, and its CIC, reactor and, most importantly, its payload of 4 planet buster 15-...
Sam Kitsune's user avatar
  • 1,994
1 vote
1 answer
226 views

How large should my supermassive planet's core be to prevent it from becoming a star?

My planet is a gas giant, it is called Klarloth (Inspired by a character from "Star Mouse" by Fredric Brown). Klarloth is a strange planet. For one thing, the planet is large in size, more ...
Alastor's user avatar
  • 3,402
6 votes
2 answers
224 views

How many different mines and extraction industries would a colony need in order to be able to produce equipment similar to what we have now?

Help me, you benevolent geology nerd! This is a question I'm trying to find a workable (but not necessarily precise) answer for a colony-building sci-fi RPG game that I am GMing for some of my friends....
Jimmy Rings's user avatar
0 votes
2 answers
280 views

Calculating the total thermal energy contained within an object [closed]

A character in my world has a superpower that allows them to convert all (or at least 99.99...%) of the thermal energy contained by the particles within a volume into directed kinetic energy, causing ...
M S's user avatar
  • 2,328
-1 votes
2 answers
165 views

How could a remote controlled bacterium work?

How could a radiowave controlled remote-controlled bacterium be possible? Criteria: The receiver for the radiowaves would not be bigger than the bacterium (which is the size of a cyanobacterium) The ...
GrimmReaper18B's user avatar
3 votes
1 answer
90 views

How the sky will change with stratospheric aerosol injections?

The world I am designing has successfully survived the event of the almost complete depletion of natural oil reserves. By "successfully" I mean that cities are densely populated, the stock ...
FrogOfJuly's user avatar
  • 1,148
5 votes
2 answers
655 views

Do the mountains formed by a divergent boundary form on either coast of the resulting channel, or on the part that has not yet separated?

The lakes and the bay are formed by the rift where the right chunk is diverging away from the main plate. I've put mountains on the land part of the rift a la Ethiopia's Great Rift Valley, but should ...
SkyDivingTortoise's user avatar
3 votes
2 answers
626 views

Physics feasibility of a light-gas driven rifle cartridge? Diagram example included

The idea would be a typical rifle cartridge with a case and propellant but with a gas section placed between the case and propellant and bullet with a soft metal disc that would be driven by the ...
J. Y.'s user avatar
  • 33
3 votes
1 answer
205 views

Is a universe with a very low speed of light possible? [closed]

In my universe, the speed of light is measured at 5m/s. Now, these aren't meters as we know them, since if all it was is just to change $c$, then the scale of everything else would change with it, and ...
The Zip Creator's user avatar
5 votes
4 answers
2k views

How does one accurately deduce scale from any given fantasy map (to the best one can)?

Sometimes, a person might wish to know the touch scale of a map, whether made by another person or you, in order to better understand the world a story is taking place. How might one go about deducing ...
Rewan Demontay's user avatar
3 votes
5 answers
429 views

Would a weapon made of a piezoelectric material be able to notably shock an opponent?

In my world, people are able to use magic to produce piezoelectric materials of a high strength, making it a viable material for use in weapons and armour. For the purpose of this question you can ...
M S's user avatar
  • 2,328
5 votes
2 answers
366 views

How close can two planets be within the habitable zone?

I am aware that similar questions have been asked but these variables are different. I have tried to calculate it myself or at least find an equation that could help find the forbidden zones for these ...
Martamo's user avatar
  • 936
1 vote
2 answers
550 views

How to calculate the density contribution of each of Earths layers

I'm trying to calculate the density of planets a bit more precise, than just treating it like an object of uniform density. In order to do so, I went with Earth, as my convenient sample planet. Earth ...
Jacco's user avatar
  • 704

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