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Questions tagged [science-based]

For questions that require answers based on hard science, not magic or pseudo-science, but do not require scientific citations. Contrast with the hard-science and reality-check tags. Do not use this tag as the only tag on a question.

-4
votes
1answer
114 views

How to create matter in a solar system [closed]

I looked to see if anything like this was asked, but can’t find. So a star is formed, the sun for instance., and creates a gravitational force on its own. After a billion years a kuiper belt ...
-5
votes
1answer
110 views

Freeman needs your help, how to get crates behind the enemy lines? [closed]

Warning: this question contains potential spoilers for Half-Life 3, but as the game will never come out, I just made a partially irrelevant warning. Garry Man is an avogadrolionaire, so he has a ...
2
votes
3answers
198 views

Could a gas giant have two earth sized moons in binary orbit around it

I’m trying to create a system where a gas giant has two moons in binary orbit with each other. I’m trying to get that James Cameron look with the gas giant on the horizon, but also have a equally ...
42
votes
8answers
14k views

How dangerous is a 500-year-old nuclear warhead?

Inspired by this question: For several excellent reasons, a 500-year-old nuclear warhead is not going to produce an actual nuclear explosion. But that doesn't mean it's not dangerous anymore. ...
5
votes
1answer
107 views

Explaining a Low-Mass Brown Dwarf

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 ...
2
votes
4answers
132 views

Can I make the carbon cycle shorter - by metamorphosis from plant to animal and vice-versa

EDITED to address the above suggestion. See below. Most animals breathe in oxygen and breathe out carbon-dioxide. Most plants take in carbon-dioxide and release oxygen. Waste products from animals ...
4
votes
5answers
265 views

How would a nanorobot disease be identified by a scientist

it's pretty straight forward, how could a scientist such as a doctor, identify that nano-robots are the cause of some disease without knowing what it is looking for ? It would somehow need to be by ...
3
votes
6answers
469 views

Can one individual be used to repopulate an entire species?

An evil scientist has engineered a plague that would kill anyone with an xy chromosome pair. This plague has systemicatically spread throughout the planet, killing all males within the population. All ...
12
votes
5answers
2k views

50% O₂ 25% Neon 23% Nitrogen and 3% trace gasses?

Could an atmosphere of 50% O₂ 25% Neon 23% Nitrogen and 3% trace gasses be survivable for a human being at the similar or slightly less atmospheric pressures as Earth?
26
votes
3answers
2k views

With 12th-15th century technology, is a “vending machine” possible?

Say that I own a business from around the 12th-15th century. My country uses a Silver (or, if you so wish, Gold) currency in the form of coins. I want to make a secure "vending machine" to give out ...
3
votes
5answers
466 views

Usability of frictionless bullets

An inventor, inspired by hydrophobic sprays, has created a spray that temporarily removes the friction of whatever it's coated on. Curiously, he decided to coat a 10mm Auto cartridge with it. With ...
13
votes
4answers
2k views

Could the moon crash into the earth if we colonised it and increased its mass?

Suppose we begin to colonize the moon. Assuming the building materials and biological material are all imported (not taken on-site), would it be possible for the moon to become massive enough to fall ...
13
votes
3answers
2k views

Is it really possible to see across a ringworld? [duplicate]

Almost all illustrations of ringworlds that I've come across tend to show off the shape of the ringworld from the surface. This doesn't seem realistic to me, because the ringworld's radius would ...
4
votes
2answers
129 views

Equation to get the size of a crater created by a meteor strike?

Im trying to find the equation to the the size of the resulting crater created by meteor strike when I have the mass, volume, diameter, density, velocity and kinetic energy of the meteor Can ...
0
votes
3answers
119 views

Can you tell me which are the things or the group of the things that the character of my story can use to paralyze his elder brother? [closed]

I am writing a fiction story. In that story, a man paralyzes his elder brother by lacing one of his food items, for example, milk or any other thing which he eats with a "thing" or a group of the "...
2
votes
0answers
115 views

What is the relationship between surface gravity and maximum animal size? [closed]

It is clear that an organism can only grow so large before the systems required to keep it alive need to become impossibly efficient. Circulatory systems, respiratory systems, nervous systems, etc. ...
11
votes
10answers
5k views

Would experiencing Groundhog Day prove that life was a simulation just for you alone?

There are other Groundhog Day questions and other Simulation questions. I believe this differs from all the others. [This movie features a] ...TV weatherman who, during an assignment covering the ...
-1
votes
1answer
92 views

What are the side effects to an ability that let's you experience the senses from a memory? [closed]

The ability gives you a photographic memory and let's you perfectly recall any event in his life, and experience all the senses (touch, vision, smell, etc.) from a memory by firing the nerves or ...
3
votes
1answer
68 views

Can giant planets in the habitable zone have rocky moons?

My question is in the context of a fictional super-Neptune that lies in the habitable zone of its host star system. Giant planets only form beyond the Frost Line of their protoplanetary disk, and ...
11
votes
18answers
3k views

A huge transparent wall permanently separates two civilisations - what can it be made of?

I'd like two medieval societies to be separated from one another by a huge vertical wall. The wall is so high that no-one has succeeded in shooting an arrow (or anything else) over it. It disappears ...
8
votes
7answers
1k views

Extreme adaptation: evolutionary narrative for Vantablack-like skin pigment

Premise Inhabiting my earth-like world will be humanoid beings that have a skin tone that is as dark as Vantablack. Let's assume these human-like beings share the same ancestry as humans and we can ...
35
votes
17answers
10k views

An object that is gold in one specific area but becomes worthless if you leave that area?

Let us pretend there is some "sacred city" created by gods, where gold is so common that it is the standard form of currency and everyone has lots of it. But once you try to leave the city with this ...
2
votes
3answers
226 views

A Wider Range of Human Skin Color — But Would The Transition Between Shades Be Natural? [closed]

Long ago, it was thought that the peoples of Europe developed white skin as a means of adapting to the low-level lighting of ice age Europe (an assumption that disregarded why the people of Asia don't ...
-1
votes
1answer
90 views

Could life be living in Europa? [closed]

The ice is so thick that no probe sent from Earth can detect life under the ice. Radio would not work well under the ice so we could not communicate with Europians if they are advanced. What would ...
1
vote
1answer
120 views

Tanks in medieval age [closed]

If people of the medieval age or 14th century had knowledge over steam engines and decided to make tanks out of it, how would it work and how effective would it be? Since they would be big and heavy, ...
6
votes
1answer
211 views

How would endo-skeletal systems adapt to the atmospheric pressures given?

Surface gravity: 1G Info regarding of altitude, pressure, and atmospheric density: ...
-1
votes
3answers
121 views

What could damage my AI character? [closed]

So I'm writing a video game similar to Rez and in this game a self-aware female AI running a spaceship gets her emotions fried (even though her shielding is powerful and emotions are firewalled and ...
1
vote
1answer
151 views

Near spherical alien species - How can they move?

The setting On an Earth-like planet but with completely different flora and fauna there is the Great Plain. It is similar in size to the Serengeti National Park on Earth. The Plain is surrounded by ...
5
votes
5answers
491 views

How would we terraform the moon?

How could we and would we terra-form the moon? I mean, theoretically speaking it should be possible and not too much of a challenge. But i don't know a lot of things, so i'm just not sure. I came up ...
0
votes
5answers
246 views

Is it possible that a species be intelligent and keep their animalistic trait?

As we all know, the brain consumes a lot of energy, so much that we, who has a bigger body and brain only have the same amount of strength as a chimpanzee. So, could a species evolve to develop ...
7
votes
3answers
132 views

Is it possible for an organic species to generate a steady magnetic field?

There are some organisms that can generate electricity (eels, for example). And some others can detect magnetic fields and use it for navigation (birds, for example): https://www.nytimes.com/2012/04/...
4
votes
5answers
211 views

Anatomically Correct Humbaba

In ancient Mesopotamian mythology, Humbaba was an evil giant slain by the hero Gilgamesh in the famous Epic of Gilgamesh. In the epic, there was only one Humbaba, but for the purposes of this question ...
10
votes
3answers
466 views

How Long Would Artifacts Last Under the Moon's Surface?

How Long? In the 1960s, unknown to most, the United States set up a secret base on the moon manned by an "extra" aboard each Apollo lander. NASA architects decided that the base must be built into ...
22
votes
13answers
4k views

Always a full Moon for the Emperor - Can this be achieved with solar panels and LEDs?

The Emperor of the World wants there always to be a full moon. His Scientific Advisor (the SA) comes up with a plan. He plans to cost out the venture, hand it over to the Keeper of the Treasury who ...
45
votes
11answers
9k views

Time Warp: Modern chemist as court alchemist

Premise The premise is an adept modern chemist is transported back in time and is to serve as the court alchemist to a wealthy prince in the late 16th century. Assumptions: "Transmuting" gold is ...
6
votes
6answers
435 views

Greenhouse Planet Terraforming - Will a balloon jacket self-stabilise?

Most of what follows is scientifically dubious. I'm looking to clarify one aspect and one aspect alone. A small planet is being terraformed by an alien race who have been doing this for millennia. ...
17
votes
6answers
3k views

Bringing Hot and Cold climates together

I'm building a map for a tabletop RPG (Pathfinder specifically), the aim of which is that my players will be trekking around and visiting interesting places. As part of that, I'd love to portray a ...
18
votes
8answers
4k views

Teleportation - the collision of matter problem [closed]

I'm surprised I can't find a previous question on this. We all know that being teleported instantly from one place to another has a big problem. If your co-ordinates are off, you might appear in the ...
7
votes
13answers
4k views

Could machine guns be produced in the 14th century? [duplicate]

Could light machine guns such as the Madsen be made during the 14th century? And since materials may be scarce only a few would be produced for use by a single soldier in a unit. Lets say their ...
17
votes
8answers
4k views

Software that shows space travel accurately in 3d from a physics point of view

An answer to the following question mentions a free online calculator for long-distance space travel. Software to ease my interstellar travel calculations I'm looking for a 3d simulator that ...
6
votes
1answer
147 views

How close from Earth could a wandering flare red dwarf star be without causing havoc?

Rewriting the question to clarify: The time and location is now in our current Earth. A wandering red dwarf flare star (like Wolf 359) is moving towards our Solar System. The question: How close could ...
92
votes
6answers
21k views

Would a Moon made of water pose a threat to Earth during eclipses?

Is a moon made entirely of water possible? Could a planet made completely of water exist? I was inspired by the above questions to ask the following: Assume that our current Moon is replaced ...
9
votes
2answers
302 views

Cost of electrolytic hydrogen

Working on a future history setting; the question arises, since the world cannot run on fossil fuels forever, one way or another, something must end up replacing them; what will that something be? A ...
7
votes
5answers
229 views

Is this sudden global cooling scenario plausible?

In the year 2071 the Dysnomia incident happened. The Dysnomia (a mining ship) suffered a catastrophic failure and violently exploded sending its payload, an aged comet, hurtling towards earth. The ...
1
vote
2answers
143 views

How to breed war elephants?

Let's imagine following scenario: Human society, mostly possessing technology on level of continental Europe, around year 1000 AD ("High Medieval Period"). There are rare, but not unknown, ...
3
votes
5answers
231 views

Scientific way for rain and pebbles to slowly fall “upwards”?

I'm looking for a scientific explanation as to why smaller pebbles and rain would slowly fall upwards without the planet itself orbiting far too close to fry every living thing on the surface. A way ...
5
votes
9answers
516 views

In what scenario would exosuited workers be more economic than automation?

In Warlords, my own sci-fi project, I wanted to tap into exosuits, but didn't want them to be one off rich boy toys or just make little to no practical sense. So I'm wondering what industry, if any, ...
18
votes
16answers
6k views

How to accurately detect children with super strength?

We are in a world very similar to ours. But, one day, 1% of the children that are turning 10 are gaining super strength (this is an ongoing process : from that date, all the children under 10 may ...
3
votes
1answer
199 views

Climate on a planet with huge tides

Tidea is a moon with an atmosphere orbiting a giant planet. Due to that, tidal forces on Tidea are enormous. I'm working on trying to understand how would the climate be on Tidea. Relevant things ...
19
votes
7answers
3k views

Aquatic aliens and the effects of acceleration in space-flight

A sentient species of water-dwelling aliens achieve space-flight. Their living quarters contain water [no free gases]. They have evolved over millions of years to regulate their buoyancy at will. ...