204
votes
Why can't spaceships go underwater?
It depends on the universe.
The problem with spaceships going underwater is that they are usually built to do only one thing. One of the most famous scenes from Futurama is when the crew's spaceship ...
118
votes
Why can't spaceships go underwater?
Spaceships are not supposed to withstand a lot of external pressure
Have a look at our sister site Space.SE and the question Do spacecraft have similar structural integrity requirements as submarines?...
- 17.8k
57
votes
Accepted
How would the lifts work on a space station which worries about hull breaches?
The same way you put weapons elevators in a warship
The US Navy has lots of very large boats that use elevators. Of specific interest are the weapons elevators on aircraft carriers, since these have ...
- 85.8k
54
votes
How big could an alien-made object on the far side of the moon become so that discovery still can only happen by accident?
Cover it in regolith
The moon hasn't seen a lot of activity in the last few billion years, leading to it being mostly covered in a loose layer of fine dust, called regolith. This layer is 4-5 meters ...
- 85.8k
50
votes
Accepted
Dyson sphere with mirrors
Building on L.Dutch's answer:
Even if mirrors are very efficient and reflect 99.9% there still remains that residual .1% of energy they absorb.
(almost) All energy is prevented from escaping and thus ...
- 17.5k
48
votes
If we can have "all the comforts of home" in space why would we settle planets?
If nothing else we would need planets for raw materials and therefore have at the very least mining colonies or penal camps.
You can't produce metals, plastics and all the rest from nothing.
Also ...
- 28.4k
46
votes
Could I build a stairway to Heaven?
A stairway into orbit? Probably not, but a stairway to Heaven, YES!
No matter how high you make a stairway, you will die of Hypoxia and/or Hypothermia long before you reach a geosynchronous altitude,...
- 105k
45
votes
What's wrong with moving cables for a Space Elevator?
The structural problems with space elevators are on a very different scale than what you are thinking of. At the lengths needed for a space elevator most materials won't be able to support their own ...
- 21.4k
43
votes
What measures to put in place to reduce airlock being used for murder?
A couple ideas:
If there's vacuum on the outside of the airlock, then the outer door can only be activated from within the airlock itself. There's also an override within the airlock to prevent the ...
- 8,340
42
votes
What measures to put in place to reduce airlock being used for murder?
Space Navy Code D.E.E.P/6 para 4
I think you're possibly looking at this from the wrong direction. You're proposing a scenario where the death penalty is a legitimate punishment. You say the air lock ...
- 41.1k
42
votes
Accepted
I want to build a weapon targeting Interstellar distances. How viable are railguns?
They even have a Dyson swarm set up that can extract as much energy as I will need
You should be building a Nicoll-Dyson beam. If you weren't aware of these engineering marvels, it involves ...
- 78.5k
41
votes
Accepted
How big could an alien-made object on the far side of the moon become so that discovery still can only happen by accident?
The latest publicly available moon map has a resolution of roughly 328 feet. Any object smaller than that would be a single pixel, and would be difficult to pick out from the background jumble. You ...
- 15k
40
votes
If we can have "all the comforts of home" in space why would we settle planets?
Because they're beautiful. I don't know what exactly your habitats offer in terms of technology, but nothing short of full VR would convince me personally to live in a space station where nature is ...
- 2,498
39
votes
Dyson sphere with mirrors
Light emitted from the star would travel until the mirrors and then would be reflected back, bouncing back and forth. Due to enormous scale of the Dyson sphere, you can neglect cavity effects and ...
- 301k
39
votes
I want to build a weapon targeting Interstellar distances. How viable are railguns?
The problem with an unguided projectile at interstellar scale isn't accelerating it, it's hitting anything at the other end.
Here's the scale of the problem. Assume that your railgun has perfect bench ...
- 38.8k
39
votes
What would happen to a star if most of its energy were reflected back at it?
The star will very slowly reach a new equilibrium.
The energy being reflected back will lead to an increase in the star's temperature, starting with the photosphere (which is opaque). The photosphere ...
- 55.9k
38
votes
How are there so many species on the space station 'A long way from anywhere V'?
Space travel was a nightmare of constant encounter suits and multiple stations sharing orbits until there was a big collision between two stations in unstable orbits around Life in Exile 5. After that ...
- 118k
38
votes
What are the feasible means of keeping a space station existing and operational for thousands of years?
You have solar power, I presume you have reasonably intelligent robots, the solution is to take a clue from biology: Constantly, whether it is needed or not, replace every molecule of the space ...
- 34.8k
38
votes
Accepted
Is a space station using a Dyson sphere like structure to power itself invincible?
The Problem of Defense:
This is a similar problem to the one envisioned by the French after WW1. They imagined the Maginot line would make France invulnerable to attack, but the Germans simply side-...
- 64.4k
37
votes
Are there any benefits to a large body of water in a space habitat?
Radiation shield
There is lots of radiation in space. There are few better shields than water. Due to its hydrogen bonds and large dipole (that is, the oxygen is negatively charged, the hydrogen ...
- 85.8k
37
votes
Accepted
Why do high-orbit space stations fall once destroyed?
It's a safety feature to avoid Kessler Syndrome.
Early in the days of space warfare, several planets got crippled by the cascading destruction of their space stations. Not only did the debris destroy ...
- 3,476
36
votes
Accepted
Aside from fueling, how would a future space station generate revenue and provide value to both the stationers and visitors?
Trading Post
Space ships for interstellar travel are different to the space ships for planetary landing. Putting both types of engines on the same ship is a waste of money.
Traders do interstellar but ...
- 66.3k
33
votes
Accepted
How are there so many species on the space station 'A long way from anywhere V'?
Many differences are quite easy to overcome. Moderate- and high-gravity-worlders, for instance, can live in a mid-to-low-gravity environment without much trouble, at least for a little while. Plant-...
- 12.3k
32
votes
Accepted
How hard would it be to find something in the void between solar systems?
Really, really, really difficult.
Space is just that big. To give you an idea of how big space is, in the science fiction novel The Stars, Like Dust, one of the plot points is that they're seeking a (...
- 40.4k
32
votes
Evacuating earth in favor of a off-world habitat: Just how many people can be saved?
0.
The amount of farming land required to support one vegetarian is measured in acres. The cost to launch a kilo of stuff into space is about 10,000 dollarydoos. This is too much to launch into space.
...
- 66.3k
31
votes
Accepted
If we can have "all the comforts of home" in space why would we settle planets?
Security
I'm surprised nobody else mentioned that already.
A space station is an artificial habitat within a hazardous environment. This artificial habitat needs to be maintained and run to avoid a ...
- 654
30
votes
Are there any benefits to a large body of water in a space habitat?
Depends on your definition of benefit. In the case of Rama the lake wasn't just a lake, it was also a machine reclamation (and presumably construction) yard where machines from anywhere in the habitat ...
- 66.5k
30
votes
Minimising the environmental effects of my dyson brain
Give your Dyson sphere an equatorial window
All of the inhabitable parts of the solar system lie along a single plane meaning that we don't need any of the sun light escaping above or below this ...
- 105k
29
votes
Accepted
Practicality of building a space station in the tail of a comet
The station is anchored to the comet
A comet's tail orients away from the star, and its size and properties change based on how close it is to the star. Because of a comet's elliptical orbit, there ...
- 105k
27
votes
Accepted
How can I prevent Kessler Syndrome among space stations?
So, if I'm understanding correctly, you're wondering how to prevent a catastrophic failure on a space station from creating debris that would be hazardous to other stations? If so, there are a few ...
- 15k
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