29

A piece of history The problem is that any material could devalue or increase in value. That makes the building susceptible to become less valuable over time. What you need is something that is expensive not just for its value as a resource. Make it valuable for its history. There's two ways to look at this. One is using relics and old buildings with history ...


22

Your harness is not a saddle The thing about horse saddles is that they are designed to help keep a rider comfortable and on top of an animal while functioning as a sort of seat with your legs going off to either side of the horse's back ... but this dragon's body is far too large get your legs around, meaning you can't just sit on it with a normal saddle. ...


18

MicroSD cards filled with legitimately purchased Music, Software, Movies, etc from your entire empire's history Superglued together into 1 cubic meter blocks, these make a great building material! Can be cut and shaped using conventional tools. MicroSD cards are 1.65 × $10^{-7}$ cubic metres. Costs \$670 for a 1tb card. A good movie compresses to about ...


17

Materials are irrelevant What matters is craftsmanship. On a galactic scale, all materials that exist are common. Theoretically all skills are also common, but getting the craftsman for hand carved oak beams is still expensive. As are hand embroidered tapestries on the walls, hand made stained glass windows (these are always expensive regardless), ...


16

Curium-247 Curium 247 is by far one of the most stable man-made elements with a half-life of 15.6 million years. It emits very small amounts of alpha radiation, but alpha radiation is mostly harmless since it lacks the penetration power to bypass human skin. A plastic coating as allowed by the OP may be recommended in commonly used areas just to be on the ...


13

It won't make a difference Technically we see the whole world inverted and upside down. The light that reaches our retinas is mirrored and upside down when entering the eye. Our brain won't use the energy to flip it again inside our head. The brain just starts associating. Touching something on a certain spot goes with a visual and proprioception stimuli. ...


11

Right now, the space is free. However, certain orbits around Earth, like Geostationary orbits are very valuable, and clash of interests is becoming common. What are the next possible steps in the development of "Space Law"? Step 1: Space is too crowded to be free for all Most companies and governments will recognize that satellites can no longer be ...


11

Their sneeze reflex If they die when they sneeze, for the most part those with a sneeze reflex would die young and not reproduce. The surviving aliens will no longer have a sneeze reflex. It's a little too much of a hole to fill in a species design.


10

Unobtanium Any material the architects can come up with can be outdone. So, the real material should be shrouded in mystery. Covering it in plastic would help to deepen this mystery. Regular people and scientists would ponder about the nature of this unobtanium, but they would never have a clue. All their guesses would be lazily dismissed by the palace staff:...


10

It's not the materials It's the location. Most of the ISS is made of things readily available on Earth; Yet it was so expensive to build because of its privileged location (and harsh conditions). Having a palace in a low orbit over Sagittarius A* would be costly due to the absurd amount of ∆v required to reach it. Might have to sacrifice a few stars for a ...


8

The saddle has saddlebags To circumvent any difficulties with buoyancy or surface, why not just add saddlebags. It makes sense for such travel to have the option to store a lot of stuff for both the driver, passengers and the dragon. The saddlebags are sealed against water for air travel. Some are likely empty or close to empty, making for great buoyancy. ...


6

I guess what would have to be worked out is getting the material from the planet out into orbit. Getting material to outer space is extremely costly. It costs $10,000 to put 1 lb. into Earth's orbit. So that cost has to be factored in the market value. Enough competition could bring that down. If there are multiple companies, they could own 3-D chunks of ...


6

If the Earth's most sensitive instruments have any reason to be brought to bear on the alien fleet... Well. Let me put it this way: from a distance of fifteen billion kilometers, a 8W transmitter can be heard by Earth equipment - and we know this because it happened, with the Pioneer probes. With no energy limitations like those probes (the Pioneer had to ...


6

Gold is currently sold at around 50 Euro/gram. During my university time I worked with an organic material which we paid 3000 Euro/gram, and it was only one of the many and similarly priced we had to use to build a OLED stack. That's the figure for any material which is produced ad hoc and in limited batches. And this is where you have to be careful: the ...


5

Property rights only exist when there are laws which recognize and guarantee them. Laws only exist when there is an authority with the power to enforce them. So if you want to turn orbital space into a commodity which is traded on an open market, you first need some organization which is willing to create rules for the use of orbits and able to enforce those ...


5

Trees Animals are very, very inefficient. To produce anything, they need to eat plants. The digestion is using a lot of energy to transform it to something usable. If I remember correctly, about 40% is wasted. Then it goes to storage, movement and thinking besides the growth of product, all which waste a lot of energy. What you need is to cut out the middle ...


5

Your planet would be hot. Quite hot. With 30% O$_2$ and 4500 ppm CO$_2$ you've essentially married the conditions of the Cretaceous Thermal Maximum, one of the warmest periods of our planet's history when global temperatures averaged up to 35°C and the poles were ice-free cool temperate regions, and the Cambrian greenhouse period, when CO$_2$ levels were ...


5

The problem is surface area versus volume. Also called the square cube law. Lungs require surface area to gather oxygen. They do this by making thin walls in the lungs where blood is on one side and oxygen on the other, giving oxygen a chance to get bound to the red bloodcells. Whenever you double the size of the creature a rough estimate gives you 4x more ...


5

Skulls of the rebels It should be a rare material, or the emperor is not doing his job very well, but if there's a shortage then he can widen the definition of rebel to include people not turning in their library books in time. The emperor controls the supply of this material by definition, so it can be as precious as he wants. Besides that, there's a ...


5

Solid Mercury Mercury has always been the material of choice for emperors when they have to do something mystical and grand, though the mercury itself is readily available for all but making something out of it, using it, and maintaining it is altogether a different story. There are certain examples where mercury is solidified to create a structure, ...


5

Antimatter. It is pretty freaking expensive to make, but the real, ongoing, terrific expense is maintaining it. Your palace of antimatter will happily explode and take half of its planet with. This must be prevented. No atom of normal matter must be allowed to touch the walls of the palace. It is good to have redundant systems for this. Perhaps on Boom ...


5

Size Matters The palace is a planet. One entire planet. To arrive you have to dock with the Official Arrival Space Station. Landing on the surface is strictly forbidden. The Space Station is the top of a Space Elevator, meaning it is stationary over a point on the surface. The reach the Elevator, you must walk across a big room with a glass ceiling giving ...


5

Tunnels of this conformation (geometrically straight and therefore dipping into and through crust and mantle) have been semi-seriously proposed as transportation systems. They have the advantage that (according to math I can't claim to understand) gravitationally driven, unpowered travel through such a tunnel (evacuated, with frictionless rails) would take ...


4

Yellow aurora. https://www.lemurialight.com/blogs/amazing-life/yellow-aurora Yellow is one of the colors possible for the aurora on Earth. Yellow is caused by charged paticles in the solar wind striking oxygen high in the atmosphere. The oxygen then emits yellow light. This happens constantly on your planet. Because of the near constant haze, the pure ...


4

It depends what precisely you mean by inverted. As others have said no-one knows how another person perceives "red". We know that colour-blind people see colours differently from those who are not colour-blind. But we know this without knowing what "red" looks like to them, but by the fact that they can't distinguish between certain ...


4

By one Orbit, get one for free Any orbit around any Planet will have 2 Major factors playing into its value. First one being Altitute and 2nd the Orbital inclination, aka the Angle of the Orbit in respect to the Equator. In General, the higher your Inclination is, the more Valuable the Orbit becomes, for a few Reasons. First one, the View. With a High ...


4

A non-rigid saddle and tropical water, you'll be fine. Technically a human themselves is buoyant in calm water. (Human is 985 kg/m3, Salt water is 1020 kg/m3). The exposure or exhaustion usually tires you out, then a wave gets you. And then your corpse floats. A horse saddle can weigh up to 20kg, and this dragon is a lot bigger than a horse. We could ...


3

There are different kinds of lava, with a range of temperatures usually around 700 to 1,200 Celsius (1,292 to 2,192 fahrenheit). So any material that can stay solid up to and above those temperatures could work, depending on your lava. Fused quartz glass, and many alloys of/with brass, bronze, copper and gold could be use for lava in the colder range of ...


3

A ceramic thermos can do the job. However, if you want it to be brittle, you have to deal with consequences.


3

The air colour is caused by a physical phenomenon, the Rayleigh scattering. Absent this, the air away from the Sun would appear black, since there would be no light coming from directions others than the Sun's (basically the same that happens in space, or going high enough in the stratosphere: from the directions where no direct light source exists, we see ...


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