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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 sinks into the ocean: Prof. Farnsworth: Dear Lord, that's over 150 atmospheres of pressure! Fry: How many atmospheres can this ship withstand? Prof....


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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? for some information about this problem. Here are a few quotes relevant to this question that come from the answers: Next, the orbital craft. To get there ...


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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: Orbital Eggshell Crumbling Civilization Obfuscator Mk I Magrathean homework assignment


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You can claim whatever you want. Calling something a country is a generally pointless designation if it's unrecognized. However, he might have a significantly better chance of getting recognized than a typical seasteader. Elon has a lot of resources and might be able to rally enough engineers to design and build this space station. If he can then use it as ...


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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 many things in common with the elevators you are interested in: they must be fire-resistant, watertight, they are large (about 40 foot vertically) and high ...


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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 thick in the smooth mares, and up to 15m thick in the highlands. Also, given that the moon's atmosphere offers no protection against cosmic rays, it would be ...


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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 accumulates inside the sphere. Temperature inside the sphere will rise (quasi) linearly. Ditto for both radiation and solar wind. It is not said if the solar ...


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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 you can't have a closed ecosystem without it eventually deteriorating, there is always a loss however fractional. Evaporation, energy, food and everything else ...


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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 weight. This is an engineering problem that can't be fixed, just by adding more cables. Each cable that is added would also need to support their own weight. ...


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Lets assume that 1000lbs(453.592 KG) is close to the limit of a single strand of his hair. Lets assume his hair weighs about the same as an average humans hair by length. http://www.answerbag.com/q_view/2159502 "a single strand of hair 4 1/2(11.43 cm) inches in length weighs, on average, 0.62 milligram" Which gives us about 5.42 mg per meter. A space ...


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New Earth Recipe: Ingredients: 32 parts iron 30 parts oxygen 15 parts silicon 14 parts magnesium 3 parts sulfur 2 parts nickel 1.1 parts calcium 1.1 parts aluminum> ~1 parts of a varying mixture of metals/metalloids/nonmetals from across the periodic table Bring all ingredients to a molten state; evenly mix until roughly 7100 miles in diameter; ...


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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 confined to parks and you cannot stand on a mountaintop and watch over miles of untouched taiga. This is an important factor for human well-being, don't ...


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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 could probably get away with covering four full pixels (so 656 feet or nearly 200 m) before people started looking askance at your structure. Note that smaller ...


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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 related wavelenght selection. This would build up energy into the sphere, which can only dissipate through the mirrors. Basically such a configuration would act ...


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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 station with newly fabricated parts, smelt down the old parts, bring in new steel or whatever from asteroids. Make so no part of your station is ever more than 20 ...


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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 it was just constant encounter suits. Luckily the airtight nature of the suits meant that the fact nobody had washed in 6 months didn't affect other travellers....


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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 positively), water interacts readily with the most dangerous radiation in space, cosmic ray protons. Furthermore, since water is full of free H$^{+}$ anyways, the ...


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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 of our solar system would not give any visible benefits. The optimal locations to establish a space station would be just outside a galaxy or in one of the arms ...


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Update: The original version of this answer was based on an arithmetic error which underestimated the required material by factor 1000. It was subsequently rewritten. How do you define "Death Star"? Depending on what your space station is going to be capable of, there is no upper bound to how complicated the engineering challenges can become. But to ...


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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 launch a bunch of rockets filled with ball-bearings or something similar, and and release them into high-speed orbits. You can have this be a temporary ...


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A large sphere, possible with engines jutting out of it. Any surface area on a fighter is somewhere to be hit, leading to either damaged (important) systems or loss of air. Surface area is bad! Thus, in absence of any aerodynamic requirements, the optimal fighter jet would be the one that maximizes volume, to fit equipment, instruments, pilot etc, while ...


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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 not fry here on the ground is because the Earth's magnetic field and its atmosphere protect us. These pretty lights are where the atmosphere blocks particles ...


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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 breakdown. A habitable planet is a natural habitable environment which regulates it self. Of course there are natural events like storms and eruptions, but we ...


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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-men, humans, and slime-molds can share the same atmosphere. Stationary or slow creatures can use hover-lifts to get around. Even some normally-aquatic creatures ...


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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 could take advantage of 3d space, and if I remember correctly also had something to do with energy storage. Anyway.. By body of water I'm going to assume you ...


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You question makes two stipulations: The alien law states only one clause: If in [the] given solar system [there] is a planet with a civilisation [that] can detonate an atomic bomb, you have to have an agreement [with] such planet. Aliens see us the same way as we see [people from poorer countries]. The conclusion you come to is that : In our ...


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The economics of mining in space are hotly contested, with some estimates claiming as much as US$20 trillion worth of precious and industrial metals in a single asteroid, while others point out that any efforts to extract these materials and bring them back to Earth en masse will necessarily flood the market and cause prices to crash, potentially (or ...


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Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space. --Douglas Adams, The Hitchhiker's Guide to the Galaxy The distances involved are literally astronomical. A "high-density area" in an asteroid belt is ...


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Well a Dyson Sphere is named after the person who popularised the idea and also the shape of the object itself. Without paying homage to a person or entity, it makes sense to call it after its function. Around a planet, there's a few functions it could have which allow you to derive a name for it. Defence: A megastructure created with the intent of ...


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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 options: 1) Failure Points This is a development of a technology commonly used on aircraft to minimise the effect of a crack in the skin of the aircraft. The ...


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