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228

Let's try to do this. (They told you it can't be done. They're right. Realistically, it can't. So, disclaimer: I'm going to employ industrial quantities of high-grade Improbability). Notes I had to play with "realize what this thing is". There's no reasonable way I can hand-wave an alchemist deducing nuclear fission. The best I think we can aim for is ...


140

It depends on your rock. Rocks like Granite, with large crystal sizes, are the result of VERY slow cooling and crystallization. So although in theory you could remelt and recrystallize this kind of rock, you'd probably need hundreds or thousands of years to do it. Basalt, a fine grained igneous rock, would be fine. It would still need quite a long cool ...


127

Evidence suggests that no creature becomes more intelligent than it needs to be, intelligence is expensive of calories, for example, human brains are about 2% of our overall mass but require 20% of our minimum calorie intake. So intelligence beyond basic survival needs is actually maladaptive for individuals and species. A gecko therefore has a biological ...


122

One reason that might play a larger part than you'd think is actually aesthetics. Sure, a big ugly ball of components is the cheapest option now, but will it net you any sponsors for your next mission? Will it inspire the next generation of potential astronauts? Will people back home look at your ship and think 'Yes, that's a ship on which I want to set ...


108

It turns out to be radioactive. It's light, it's beautiful, it's strong. ... but anyone who carries or wears the metal for more than a very short period of time eventually gets sick. This wasn't known during the initial gold rush and the metal was used to make various things... but eventually the people who handled it most or wore or carried pieces got ...


92

...once they reach a planet, they do research. Nope. They're doing research all the time. That's their full-time employment. Aside from the usual time off, it's nonstop research. Once they reach a planet, they do fieldwork. That means collecting samples, interviewing or observing people, observing animals, taking careful notes and pictures, measuring ...


85

Titanium is actually a fascinating example standing by itself, because it's not that hard to find (it was identified as an element before 1800, and is the ninth-most abundant element in Earth's crust) but it's very difficult to work. Titanium can't be shaped simply by heating it and pouring or working it like you might do with iron, steel, brass, or the ...


77

Utterly impossible. You simply cannot have one pole of a rotating planet always oriented the same way towards the sun, for the simple reason that the pole always points in the same direction in space, but the planet moves around the sun. Keeping one pole always pointed at the sun despite the planet moving from one side to the other over the course of its ...


76

For your reference: some years ago in Brazil a scrap thief, while salvaging through the remnants of a hospital, found a piece of material which emitted a nice glowing blue light. He was smart enough to think "wow, this will make a pretty good gift for my wife", and tried to take it with him. Long story short: 4 dead and various contaminated from a piece of ...


72

If you're a billionaire and already under the focus of the TLA Agencies, best how to disappear for a year is... not to disappear. If you'd suddenly disappear from today to tomorrow a dozen of alerts will go of with every single agency, not only from the government. Even more if you're already known as a mad man. So you need a perfectly instructed body ...


70

Space isn't a pure vacuum. There's still bits of rock and other debris floating around. Do you really want masses impacting your ship at fractions of light speed? Streamlined designs would have anything hitting you from the front sliding off at at angle, instead of transferring all the momentum to one point on an airtight vessel in a vacuum. The ones ...


70

I am not sure where the energy would come from for this It would come from the scanner itself. In order to make extremely-high-precision scans, the scanner itself has to direct considerable energy at the target of the scan. The more precision you want, the more energy you need to pump into it. Much of that energy is absorbed by the target, which is what ...


69

Radiation Hazards, or why I learned to stop worrying and build my ships like skyscrapers. One reason among many is to shield the crew from Radiation. Not incident interstellar radiation, though - radiation from your own ship. Since solar isn't really an option in the dark interstellar void, chances are you're using some variant of nuclear power, fusion or ...


68

I would think so. Innovation is probably the hardest bit and duplication is much easier. We see it with computers all the time now. Some small company comes up with a new idea that is "obvious" and then suddenly everyone else can duplicate it. The same is with other STEM fields, the knowledge that it exists (and ideally something to experiment with) helps ...


67

It's due to the nature of vampires, and their regenerative state. If a metal or other non-organic substance is thrust into their body then over time their regenerative abilities will push it out. Even if they are completely impaled the stake will gradually migrate as the body moves to one side of the coffin or the other. Use a material that was once alive ...


65

According to astronomer Greg Aldering, the scale of the void is such that "If the Milky Way had been in the center of the Boötes void, we wouldn't have known there were other galaxies until the 1960s." If your aliens live on isolated star(though it would be hard to explain - see star formation process) in the middle of void then they simply would not see ...


60

Now, a few answerers have claimed that the stake need not be wooden. While this may be true in the traditional vampiric lore, we exist only to answer the specific question here. Why Wood Vampire Blood contains a specific set of proteins and nutrients that allow for almost instantaneous regeneration. These proteins are denatured by heat (fire), and cannot ...


54

Test her limits. Can she move more than one thing at once? If so, how many? How large of a thing can she move, both by weight and by volume? Is there a minimum size an object has to be, or could she move individual atoms if she wanted to. How fast can she make an object move? Are there any range limits on her telekinesis? Can she move an object she cannot ...


54

This "weapon" has already been built. It's called the European X-Ray Free Electron Laser (XFEL), and it's used for super-accurate imaging of molecules. Point is, whenever the XFEL hits a target molecule, all the electrons are simply blasted away from the molecule, and the more inert rest of atomic nuclei dissolves in a Coulomb-explosion. The scattered X-...


53

Move the space race earlier. 1931. There are not transistors or nuclear power because neither has been developed. But space is in reach. from http://www.computerhistory.org/revolution/calculators/1/44/157 1925: The Treaty of Versailles is enforced, and German re-armament does not happen. The Germans are, however, recognized to be masters of technology ...


50

I am a scientist. Although I mostly do computational/theoretical work, I have a lot of colleagues who are chemists, geologists and biologists. Just like the scientists in your question, these people spend only a small part of the year on location gathering data. For most of the rest of the time, we are in our institute/spaceship engaged in one or other of ...


48

Nope. Not very useful in the way you proposed. Just imagine using a tank on a treadmill as a battery to fuel a ship: you'll lose a lot of power, unless you have a zero-cost source of tanks and fuel for them. Any animal (including a human) needs a power for his systems to be alive and running, so making a living organism into battery by using one of his ...


47

By doing it every couple of years in some totally innocent way. Some years you spend sailing in the Southern Ocean, some years you spend 6 months skiing in the Alps or solo trekking across the Australian outback. Eventually they get used to your disappearing for months at a time and it taking them slightly longer than they'd like to work out where you are ...


45

This seems to be the key sentence in the question: "It claims no moral authority of right and wrong, but supports progress.". So "good" can be defined as that which advances progress, and "bad" that which hinders it. And that's where the "moral authority" actually does reside in this world. What is the definition of "progress"? In our real world, we ...


44

This dude estimates the work done by the human heart as 0.5 J/beat. Assuming a resting heart rate of 60 beats / min, that gives us 0.5W of power, or 43.2 kJ per day. Assuming a 115 lb person sleeping burns 42 Calories (which are kilocalories) / hour, that means you need to ingest about 1008 kilocalories a day to be an unconscious blood pump, or 4.2 MJ. So ...


40

Euler Euler was a brilliant astronomer, but unfortunately he probably wouldn't be able to get a job in modern astronomy without a college diploma, much less without a high school diploma. He was also an excellent mathematician, though, and I think that is his best bet in the modern world. It seems likely that Euler would find a job as a programmer (once ...


39

Clouds Different types of clouds sit on different layers based on altitude, air pressure, and relative humidity. You mentioned your atmosphere has breathable air, does it also have water vapor in the atmosphere? Are there rain clouds? Methane clouds? Sulfur Dioxide clouds? Maybe an enterprising character notices that the moisture collectors are collecting ...


39

In addition to Ash's answer: You assume that every lifeform spends its entire life learning indefinitely. This is just plain incorrect. Not only could you look at the elderly of most species and see that at some point the intelligence does not seem to improve anymore or in some cases by tendency degrade in old age. (e.g. Humans) But some animals learn very ...


38

I admit up front, that my first reaction was to consider the comedy potential of this situation, as the device might have labels on it. That would make a big difference - think of the warnings on a bag of peanuts or a chainsaw, and enjoy imagination ("warning: this product may destroy large cities.", "user safety information: this product can cause cancers."...


37

A common misunderstanding about theories in general is that you can prove them, when in fact you will never be able to prove a theory - you can only ever falsify a theory. There is simply no way to prove that a theory will always apply to every case that it's supposed to be usable for. You can only ever falsify a theory and thereby say that it doesn't work ...


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