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49

If the glass is unflawed, the opening will look like a flat, nearly-black mirror. When you look at glass, you see a combination of the light reflecting off the surface and the light coming through it. (Think windows at night.) This is the key to Pepper's Ghost. In this case, there will be no light coming through the surface, since even glass isn't ...


48

Strange thing? We already stack the Earth. Not quite as grandiosely (is that really a word??) as you're asking for, but when you think about it modern cities, especially those with skyscrapers, are attempts to do exactly what you're doing. So rather than getting the world engaged in a megaproject to build a series of 100km high shells, instead get the world ...


48

Consider the following: The diameter of the Earth is 12,742 kilometers. Our planet's crust thickness is anywhere from 30 kilometers on the continents, to 5 - 10 kilometers on the ocean floors (which have not been explored or mined in any real detail). The deepest mine on the planet goes down less than 4 kilometers. Your average ground penetrating radar does ...


42

The Earth is better surveyed than is generally realized. It is probable that geophysical survey techniques would have revealed the existence of an underground megastructure. Geophysical surveys may use a great variety of sensing instruments, and data may be collected from above or below the Earth's surface or from aerial, orbital, or marine platforms. ...


37

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 ...


32

I think the best solution would be a Matrioshka Brain. This is effectively a layered set of Dyson spheres. Once it reaches equilibrium, each shell has a particular temperature differential across it, which can be used to generate work. These shells feed eachother, so the total temperature drop across the entire brain is equal to the temperature of the ...


30

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 ...


26

TL;DR: Yes, helical motion around a ringworld is possible. However, it is far from uniform at larger distances (≥ 0.04 AU). Summary of results: For a toroidal ringworld with mass $M_R = 3 M_\text{star} = 3M_\odot$, central radius $ a = 1 \text{ AU}$ and inner radius $b = 10^{-4} a \simeq 15000\text{ km}$ (hence density $\rho \sim 8800\text{ kg/m}^3$, ...


23

Could an arrangement of three or more proximal stars produce one or more points of balanced gravitation pull, each of which could hold a planet such that it would rest in a stationary position relative to all stars in the system? Not exactly It would be similar to Lagrangian points. L1, L2, L3 are totally unstable. But L4 and L5, unstable on their own, ...


22

Also worth touching on refractive and transparent colour - which can vary wildly depending upon specific trace elements in the glass... and which can also significantly impact reflectivity and refractive index - as can heat: some glass compositions, when unevenly heated, create surface coatings not unlike thin film, which then hugely impact refractive index -...


21

Lasers. You don't need to destroy the debris, just push it out of the way by the slightest amount. The vast majority of space junk is tracked, as others have mentioned, so you'll know what's a threat long before it actually hits. Hit the debris with a laser to alter it's path slightly and you can avoid collisions. Because you can track most of the debris, ...


17

Offices, storage, light industries and heavy industries have different requirements. Offices are best located in the commercial zone. They need to be near to restaurants and bars. A good amount of clerks can not function without a coffee in the morning. Short term storage should be placed in the best comunicated areas, so near your main internal roads/...


16

Whatever or not an artificial structure in space would be deformed to a sphere due to gravitational forces depends on the material. That tells us the gravitational force and the effort-deformation index. Known cases Now, under that idea that we are talking about a.. dwarf planet stretched into a snake like play-dough We can look at the paper The Potato ...


15

Sea based near the area of Curacao seems a good choice. http://www.hurricanecity.com/city/abcislands.htm Aruba,Bonaire & Curacao Islands history with tropical systems Longest gap between storms 25 years 1892-1918 How often this area gets affected? brushed or hit every 6.50 years Average years between direct hurricane hits.(5) once every 28.60 years ...


15

Feasible Only with a Decreased Internal Pressure and Great Difficulty This is a very complicated problem with many variables that affect the final outcome of the design. I made a few assumptions throughout and played with the numbers as much as I could in order to give a semi-complete answer. I feel like I could write an entire book on how this could or ...


15

In order to keep your dyson sphere hidden, you don't really have to do anything. There's two key things to keep in mind. The whole point of a dyson sphere is to extract as much useful energy as possible to do useful work with. There's a maximal efficiency of any method to extract work from heat energy, and that efficiency is determined by the difference in ...


14

You won’t find an arrangement of 3 or more stars in a stable configuration to begin with, other than those having vastly different sizes so the little ones orbit the big one like planets, or a hierarchical binary configuration. A Klemperer rosette could be engineered, though. These are still not stable and perturbations will eventually destroy it if not ...


14

You can use the concept of a decompression chamber with two doors, one to the outer, one to the inner environment. When it is open to the outer environment it is closed to the inner. Submersible can enter the environment from the outer (or leave to it). When the outer door is closed the pressure can be adjusted (and some water removed) to match the inner ...


14

If there is a gap between the sections of the ring, it would allow all the atmosphere to spill through the gap, like so: The question really isn't one of how long of segments you need (the answer would be "all the way around the circle"), but one of how to prevent the atmosphere from spilling out the ends. Here are three suggestions: Do what Trump wants. ...


13

As mentioned in other answers, other than using super-tech, keeping a tiny star operating with out massive gravity is a problem. Fuel is another. I would suggest going more artificial and less pet-star. Normal stars, operate naturally due to gravity, and they hold together a solar system with that gravity. Your Race/Government has no need for an actual ...


13

The most sensible way would be to avoid having an internal dock altogether. IF a capital ship needs auxiliary ships like lighters, sensor drones or cutters to carry landing parties, they should be held in external cradles. This provides several advantages. Firstly, the ships can be deployed and recovered much more quickly than through a hanger or landing ...


13

Anywhere from ancient times to the present. Question 1: Is there anything there? (answered pretty quickly) Sunspots, for instance, were first observed by the Chinese in 364 B.C., two millenia before telescopes or camera obscura were first used to study the Sun! While I don't know what the Chinese used, you can see sunspots using a very basic solar ...


13

Space elevators do not have to sit above the equator. See, for example, Blaise Gassend, “Non-Equatorial Uniform-Stress Space Elevator”, 3rd Annual International Space Elevator Conference, Washington DC, June 20, 2004 (or his web page); or consider the "forked" design popularized in Kim Stanley Robinson Mars trilogy. You don't say what a "forest" means. Let's ...


13

It is called star lifting, and is a known concept. Basically, you generate a magnetic field which channels solar radiation through the poles. The magnetic field is created using orbiting electromagnets powered by the sun itself. There are three variations of this technique in Isaac Arthur's Youtube series. https://youtu.be/pzuHxL5FD5U


11

Actually, I think this is a non-sustainable situation. Given the law of gravity, the planet will be pulled in one direction or another by other orbiting bodies, if not the host star itself. Essentially, anything with a gravitational pull will affect it, and therefore will force it to move in one direction or another. Should you find/create a situation in ...


11

I must disagree with AndreiROM on this. I believe it would have been found some time ago. I'm thinking specifically of oil exploration. They go all over the place looking at subterranean layout to figure out where it's worthwhile to drill for oil. If it's drillable they're going to have a look--and your loop is certainly going to pass through some ...


11

You have a very big problem with your 2-5 km. depth. The average depth of the Atlantic ocean is over 3 km. I suspect it would have to be deeper than 5 km., and it would not be a perfect ring. And forget about around the equator. If you went pole to pole, along roughly 30 degrees west - 150 degrees east longitude, you pretty much miss all land mass and ...


10

An Alderson Disk suffers from almost all of the same problems that a Niven ring world does and has a couple unique to its configuration. Instability One problem is that the structure / star configuration is dynamically unstable. If you perturb the disk / toroid (by say a meteor strike), then it will most likely (eventually) hit the star - to the extreme ...


10

Yes! We absolutely can make a space elevator on the Moon with current technology. The lower gravity means we can use materials we already know how to mass-produce, such as "Kevlar, Spectra or M5 Fibre", and we don't need to rely on carbon nanotubes or graphene (which we can only produce in small quantities). A lunar elevator would be longer than an Earth ...


10

Being careful with your aim You can't not radiate, so if you want to not be observed then you need to make sure you aren't radiating in the direction of your nearest neighbours. To do this you'll need to somehow channel all the energy into a series of directional beams that are aimed in-between the stars closest to you. The amount of power you'll need to ...


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