29
votes
How can we make an alien atmosphere breathable, but uncomfortable?
Uncomfortable is a matter of tastes and culture, but I guess thiols make a good candidate for making an uncomfortable environment: proximity of rotting eggs, sewers, rotting algae are just few ...
26
votes
If all humans of this era suddenly became fast enough to dodge bullets, how would this change the military's choice of weaponry?
It'd change less than you'd think.
Bullets aren't the only kind of weapon out there, and there are plenty of weapons designed explicitly to be hard to miss with.
Volume-of-fire would be king.
Contrary ...
24
votes
Accepted
How can we make an alien atmosphere breathable, but uncomfortable?
Carbon dioxide.
According to some tellings, Earth arose very near the inner limit of the "habitable zone" around the Sun. Earth life sucks up nearly every trace of carbon dioxide available ...
18
votes
How can we make an alien atmosphere breathable, but uncomfortable?
There is a discussion about how much of various gases are necessary for humans to survive in Stephen H. Dole Habitable Planets for Man, 1964.
https://www.rand.org/content/dam/rand/pubs/...
16
votes
How can we make an alien atmosphere breathable, but uncomfortable?
Heavy Air
70% of Earth air is Nitrogen. This is nonreactive and harmless to your lungs. If you only breath Nitrogen you will asphyxiate. But it is not the Nitrogen that kills you. It is the lack of ...
13
votes
How can we make an alien atmosphere breathable, but uncomfortable?
Simply humidity can make breathing uncomfortable.
Humidity can make the air feel heavy. Figuratively, because actually humid air is lighter than dry air. The reason is that water vapor molecules are ...
12
votes
How can we make an alien atmosphere breathable, but uncomfortable?
Ozone.
Ozone is formed by the action of UV radiation on oxygen and other atmospheric components. It is a normal and protective component of the upper atmosphere. It is also a normal minor component ...
11
votes
Is orangeish water posible in an alien planet with advanced Life?
Water is Blue
Water is blue. But only slightly blue. In small amounts, the blueness is too weak, and the water is the colour of whatever is dissolved in it. For example mud and coca cola are brown. ...
8
votes
Accepted
Why would some species from the Homo genus be much more likely to be autistic than Homo sapiens?
They Serve a Critical Function: Culture.
The nature of the critical function should probably somehow relate to the common feature that these three races have in common: isolation. All three species ...
6
votes
Is orangeish water posible in an alien planet with advanced Life?
It already can happen on earth! All you need is some organism in water that is orange. Those already exist.
This phenomenon as far as I know typically happens in saltwater lakes. Many lakes have ...
5
votes
How would life develop/adapt in an Earth-like planet but with less sunlight?
Fungus is now king
Most plant life on earth survives via Photosynthesis.
Fungi however do not. They thrive in low-light conditions and dark, wet places.
Your twilight world is a place of spores and ...
4
votes
Accepted
For how much and for how long would a "Closed Cycle Nuclear Thermal Rocket Engine" generate thrust for a floating ship?
Not with Modern Reactors
Kori Nuclear Power Station, South Korea
This guy has a bunch of reactors. The biggest one has output of 1400MW. Construction started in 2009 and they turned it on in 2019. So ...
4
votes
Accepted
How would life develop/adapt in an Earth-like planet but with less sunlight?
It would depend on how much less light.
Because the major issue is the energy balance.
If there is less sunlight this implies less energy.
Less energy means lower average temperature.
Lower average ...
4
votes
How can we make an alien atmosphere breathable, but uncomfortable?
I already upvoted one answer, but you said you wanted this galactic standard atmosphere to have a high oxygen level and that could in itself be the problem. Being so reactive, oxygen is toxic when you ...
4
votes
If Earth was less massive, with 25% less gravity and an atmosphere scaled down proportionately, how would that affect climate?
If Earth had the same diameter and it's mass was reduced by 25 percent, its gravity would also be reduced by 25 percent, but it escape velocity would be 86.6 percent what it is now.
To put that into ...
3
votes
Why would some species from the Homo genus be much more likely to be autistic than Homo sapiens?
No specific reason is needed, they are or aren't.
To support that, it possible to look at any mammal - they do have brains, and some cognitive abilities. Many of them have problems to communicate with ...
3
votes
Can we have a mycelium tech-tree?
Drugs. Maybe Houses Too.
The only example that comes to mind is how Penicillin is produced by a fungus. It is believable that other funguses could be genetically modified to produce other useful drugs....
3
votes
How to place multiple small moons and one large moon in stable orbit around an earthlike planet?
Keep your distance
Don't count on resonance I would say, this is a many body system. Keep their orbits apart.. far apart. Chaotic systems rely on statistics. The more these moon orbits are apart in ...
3
votes
How would life develop/adapt in an Earth-like planet but with less sunlight?
What your describe pretty much nuclear winter but far longer. Your world is covered an ice and snow. The oceans are frozen over.
Plants and animals would die in mass. You would have lower ...
3
votes
For how much and for how long would a "Closed Cycle Nuclear Thermal Rocket Engine" generate thrust for a floating ship?
Just use propellers
We can find out how much water we need to fight gravity by simply dividing gravitational acceleration by the specific impulse. Using your specific impulse of 20 kNs/kg for a closed ...
3
votes
What could reduce sunlight on an Earth-like planet?
Change the humans, not the sunlight
My goal is an alternate Earth with just the sunlight being missing.
You still need the light of the sun for heat and growing food and stuff; so, instead of ...
3
votes
How might a lower gravity planet sustain a warm, earth-like atmosphere?
More atmosphere
https://www.coursehero.com/study-guides/astronomy/the-massive-atmosphere-of-venus/
...as percentages, the proportions of the major gases are very similar
for Venus and Mars, but in ...
3
votes
How long until all detectable space debris leaves orbit of a planet?
Let's consider an existing, well-studied case: Saturn's rings.
Due to the recent Cassini mission, we now suspect that they are maybe 100 million years old, and can be expected to survive for roughly ...
3
votes
How could people survive teleporting into the atmosphere while surrounded by vacuum?
Change route
Instead of going up, go down.
Teleport into the crust.
You will make a cave a few kikometers deep into the crust. It will be hell hot, but the ceiling could last longer than fifteen ...
2
votes
If all humans of this era suddenly became fast enough to dodge bullets, how would this change the military's choice of weaponry?
The simple answer is that somebody would build a better gun. For example, they would switch to a scattershot weapon that put out a wall of fire to large to easily avoid, or they would use a gun with a ...
2
votes
Would 25% less gravity produce dramatic differences in animal morphology?
Everything weight only 3/4 as much as the same mass would on Earth.
Thus, for a given mass that must be supported, and constant material strength, compressive structures can be about 87% small in ...
2
votes
Why would some species from the Homo genus be much more likely to be autistic than Homo sapiens?
Evolution
All three species are solitary. It makes evolutionary sense they would not have as developed a social structure as real humans. There is no need to be as good at reading faces or judging ...
2
votes
How can we make an alien atmosphere breathable, but uncomfortable?
Dust or pollen in the air can make breathing uncomfortable causing frequent sneezing and such. Not enough to die from, but certainly uncomfortable.
Some people are more resistant than others, and I ...
2
votes
How can we make an alien atmosphere breathable, but uncomfortable?
Overly warm and humid can make things almost unbreathable over a prolonged period. Like if you are in too hot a shower for too long. You do not want to experience that.
2
votes
Accepted
How much energy I would require to make a piston to move as fast as human muscle?
Energy isn't your problem. A tiny votive candle has enough chemical energy to blow up your house, if you could magically convert it all into mechanical work all at once. Mechanical power is the ...
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