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 ...
Community wiki
119
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?...
63
votes
What is a Dyson Sphere around a planet called?
A Dyson Sphere is meant to capture radiation and convert it to usable energy. Since an earth-like planet only reflects light back, that point would be moot. In any case, here's some suggestions:
...
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 ...
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 ...
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 ...
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 ...
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,...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
37
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-...
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 ...
35
votes
Accepted
Would Space Voids be good building for massive space stations?
No
The Solar System is really tiny compared to the scale of a galaxy. Space Voids, specifically Boötes voids are areas where the density of galaxies is less than normal, and space stations the size ...
34
votes
Accepted
Way to block rockets from entering space?
Space Debris presents a serious risk to anything in orbit. Normally, responsible space-agencies try to minimise the amount they produce, but if you wanted to make going into space difficult, you could ...
32
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-...
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 (...
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.
...
31
votes
What would an asteroid base look like and how would it operate?
Underground base
The base will need to be underground to provide protection from radiation. Even just being in Earth orbit is a major radiation hazard when the solar wind is heavy. The reason we do ...
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 ...
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 ...
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