Questions tagged [hard-science]
REVIEW THE WIKI BEFORE USING THIS TAG! For questions that require unequivocal proof that answers are correct through the use of equations, empirical evidence, scientific papers, etc. Compare to: science-fiction, science-based and internal-consistency. This tag may not be used alone. This tag may not be used with the science-fiction, science-based, or internal-consistency tags. Flag your question for moderator attention once posted.
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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 ...
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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 ...
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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 ...
CommunityBot
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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 ...
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How long would my pseudo-aurorae be visible?
I have asked questions like this before, relating to a phenomenon on my planet that is called pseudo-aurorae.
Background
X-rays of the [O VII] forbidden line in my star are constantly forming due to ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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,...
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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) -...
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How fast do you have to be to punch through a steel door?
Assuming the person is durable enough to not break his hand, how fast would he have to move his fist to punch completely through a solid steel door that is 1 inch thick?
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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 +...
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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 ...
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What are the most likely effects of a human(oid) shape moving at Mach 50 to the surrounding environment?
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 ...
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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 ...
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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 ...
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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 ...
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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.
...
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Stealth in Space: How realistic is it?
This has been considered other places on the net, but I thought it would be good for the hard-science challenge, since it is often an example of the subtle difference between soft and hard science.
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Body plan of a 4D human-analog?
I am attempting to design aliens that live in a universe with a 4+1 space-time--i.e., a universe with four orthogonal spatial dimensions, rather than three, in addition to a fifth time dimension. In ...
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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 ...
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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 ...
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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). ...
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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-...
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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 ...
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TotalRewind™ (brain chip)
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 is ...
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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....
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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 ...
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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 ...
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How to Calculate Apparent Magnitude/Brightness of Planets from Within the same Solar System
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 ...
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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 ...
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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 ...
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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 ...
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On the tidal heating of a moon. What is the second Love number?
Years ago it was asked here how to calculate the tidal heating of a moon orbiting another body with a simple equation. The answer is very detailed. They explain the equation, its shortcomings, the ...
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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 ...
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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 ...
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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 ...
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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 ...
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What color should my planet's skies be?
Assuming the skies are clear of suspended particles, what color should they be at mid-day if viewed with human eyes?
The planet is larger and twice as massive as Earth, with a nearly identical ...
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How much diamagnetic levitation can a human handle?
One of the limitations to human space travel is acceleration limits. We'd really like to just shoot spaceships out of a cannon to 99% the speed of light, but the resulting pressures on the human body ...
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What is the difference between a pulsed particle weapon and a beam particle weapon?
I'm considering adding a particle based weapon within my setting. It would be used in atmosphere and utilise [electrons] (http://www.projectrho.com/public_html/rocket/sidearmenergy.php#id--...
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What is the theoretical maximum number of habitable planets in one solar system?
In the DC comic book universe, the Vega System is a solar system around the star Vega (Alpha Lyrae), which is depicted as having dozens of habitable planets. While it seems to be an implausibly large ...
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What more than sentience do you need from a species for its intelligence to be recognizable by humans?
It's becoming obvious from how could humans recognize another species as sentient / intelligent that recognizing another species' intelligence is very complicated. There are no universal tests, no ...
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