# Tag Info

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Nothing will happen until you get enough gold to overcome electron degeneracy pressure. Then your gold fuses into one ginormous nucleus and the protons capture the electrons.

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Not really a star, but it could still shine. As others have said, no fusion would happen. However, depending up how you add the gold, it would fall until it hit the current mass. For examples, meteors impact the earth at speeds greater than escape velocity (at least when they impact the upper atmosphere) Earth escape velocity is about 11.2 km/s. Solar ...

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As noted, Iron is at the end of the curve of binding energy, and when the fusion of heavier elements ends with iron, you cease the fusion reaction. The core "goes out" and the massive gravitational energy of the star draws everything back towards the center (up to now, the energy of the nuclear fusion reactions have been "pushing back" against the ...

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You would use all the gold as gravitational mass to produce fusion of hydrogen in the center. Stars burn by fusing light elements; hydrogen at first, then helium and so on. As has been pointed out in other answers, once you get to iron you do not get energy back from fusing elements. Heavy ones like gold are only created in supernovas that have loads of ...

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Unfortunately, no matter how much pure gold you add to your mass, you will never end up with a star. The reason for this is that fusing gold is an endothermic process, meaning that it requires energy, rather than releasing it. In fact, all elements with an atomic mass greater than or equal to that of iron consume energy upon fusing, rather than releasing ...

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This star would not fuse gold. Fusion reactions producing elements beyond zinc-60 are not energetically favorable; they are endothermic, and so consume energy. Several elements heavier than iron are formed through this fusion chain and subsequent decay (cobalt, nickel, copper and zinc), but these are unstable and decay back to iron, meaning that iron is ...

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Escaping from the Earth is extremely hard. In order to reach orbit ~90% (depending on a range of parameters) of a rockets mass must be propellants leaving just 10% for the rocket engines, rocket structure, avionics (and payload). So a planet with 1.5x the gravitational pull would probably not be practical to escape from as an exponential relationship exists ...

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This is quite a difficult question to answer fully, because rocket science is hard. There are three things you need to do. Boost your rocket high enough that it leaves the atmosphere so you can enter a suitable orbit (I'll ignore boosting straight into an escape trajectory for now). Boost your rocket out quickly enough that you don't spend more time (and ...

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There are three significant limitations that enter into this question. First, thrust to weight ratio. This determines how much fuel you can actually lift off the launch pad. If the rocket weighs more than the thrust the engines can deliver, it'll just sit there until it burns off enough propellant to be able to rise. The usual rule of thumb is that ...

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Density of lava varies a small amount, but you can more or less handwave it as an average 2800kg/m3, which is roughly the density of Earth's crust. This is the important figure for your needs, because it is substantially higher than the density of humans, who can float in water, which has a density of about 1000kg/m3. The second most important figure is ...

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As noted in another answer, magma is both several times as dense as a human, and (mostly) has a relatively high viscosity, more like freshly poured concrete than anything we'd normally think of as liquid. Given the question allows for small foot extensions (a few centimeters), a human equipped with suitable protection (assuming the protective wear doesn't ...

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Given that sort of hand-wavey protection against heat and toxic fumes, it would certainly be possible to walk on lava, though you would have to keep walking or sink in. Lava is a non-newtonian fluid, and there are plenty of examples of people walking on non-newtonian fluids like oobleck (a mixture of cornstarch and water), custard, and cold oatmeal porridge ...

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It depends on the lava First to answer the question about consistency. Most lava streams are very shallow, density wise it is like walking across something between wet cement and hot taffy (or oobleck). Lava varies in consistency due to composition and temprature so I can't get more detailed than that. Lava varies widely in consistency, so you can pick ...

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It would be not walking, but sort of swimming. Since lava density is times more than that of humans, even quite a shallow stream (about 40-60 cm) foot would not touch the bottom. But lava is still a liquid - a human would not be able to stand or walk on it, unless hi/she is an acrobat with special training in liquidwalking. So the human would just float on ...

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First, two points need clarification: DeltaV is mostly determined by exhaust velocity. Since the description of the ships suggests they are powered by a mass driver acting as a rocket engine (which also doubles as a weapon), you are ultimately limited by the velocity the mass driver can project objects. What you are probably thinking of is ISP, the figure ...

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You asked "Is there any way to calculate it?". The answer is yes, but it's not going to be as simple as plugging a few numbers into a simple formula. You'll need a general circulation model. The reason is that the heat transport around the planet involves the atmosphere and the oceans, and these require dealing with fluid dynamics. This is going to bring ...

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With a nuclear reactor there is almost unlimited energy to mechanically push against the ring objects, so infinite delta V. Weeeeell... yes and no. Your reactor fuel isn't infinite, for one thing. More importantly though, your ability to accelerate is likely to be heavily influenced by your choice of reaction mass. You'll want to be throwing it away from ...

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Quora. How many people can a cruise ship take? The currently largest passenger ship in the world... can carry over 6600 passengers (all berths filled) plus about 2200 crew. So almost 9000 people in all. 1- Start a cruise line. Hire humans to get permits on both sides. Run back and forth while never taking any actual humans. If the population centers on each ...

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@M_A_Golding notes: An objective outside observer might consider orcas and other cetaceans to be intelligent beings This suggests another possibility. If you can engineer "humans" with alien minds, why not whales? Then your near-humans could collaborate with these near-whales to cross oceans somewhere warmer (or not, if they have sufficient protective ...

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There is already a very detailed answer. I would just like to add that perhaps it helps to zoom out a bit, before we drill into the actual battle with all the numbers and tactics. All battles in history share some generic categories, and i do not see why a space combat will not: Guerrilla: Weaker side uses strike and return, pointing at long term wearing ...

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I am going to claim expertise on this issue for a major reason: I live in the Arctic. I've also participated in search and rescues in the Arctic. The basic answer to this is that small groups of sufficiently-prepared people actively trying to evade detection and if no one is specifically looking for them can do it trivially by any number of means. It's hard ...

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I agree with other answers that going by land through Alaska and Siberia and crossing the Bearing Strait at a relatively narrow point might be much better for your invaders than crossing hundreds or thousand of kilometers or miles of the Arctic Ocean. Crossing the Arctic Ocean can be quite dangerous. If they cross in groups using dogsleds they will have ...

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As the previous answer mention it, it will be easier by Bering Straights. I don't think they can go "undetected" but group from 4 to 5 may go unnoticed (they will be seen, but it will not be seen as a unsual thing). Here you can go by remote terrestrial areas where it may be easier to hide in case of a recon flight, than on the ice sheep. But if there are ...

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Consider different parts of the globe, in the real world. Illegal immigrants are trying to walk across quite inhospitable terrain at the US southern border. Some are caught, many get through. Illegal immigrants are trying to cross the Mediterranean on small watercraft. For some, the goal is to be rescued by ships which do not return them to Africa. For ...

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A mistake you may be making here is that it's not a scientific hypothesis the main character is trying to prove. Rather, you're trying to prove a historical fact about something(s) that happened or didn't happen. The whole idea of the supernatural, or miraculous, is that it isn't natural. Let's say that the main character has observed objects levitating ...

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You can't "prove" anything about anything. All you can have are events separated in time and a narrative to link them. Let's say you flipped a switch and a lightbulb started illuminating a room. The only things certain are that you flipped the switch and that the lighbulb started illuminating. All the electromagnetic, quantum, theory that tells us about ...

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Electromagnetic or magnetic induction is the production of an electromotive force (i.e., voltage) across an electrical conductor in a changing magnetic field. This is correct, but the operative word here is "changing". Specifically, Faraday's law states $$\nabla \times \mathbf{E} = - \frac{\partial \mathbf{B}}{\partial t}$$ If you're not familiar with ...

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No need to introduce a new one. Eris is the goddess of discord. She discords of other gods so much that her planet has an orbital inclination of 44.1444 degrees. She doesn't want to orbit in the same plane as other planets. Makemake and Haumea hace inclinations of 28 degrees, for consideration. The trick here is that those three planets are way far from ...

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If there are some gas giants, the things will evolve pretty quickly towards an ecliptic plane - tidal forces will dissipate the energy fast enough to get the system evolving to a maximum moment of inertia with the minimum kinetic energy. Rocky planets orbiting far from the gas giants may persist longer on inclined orbits, but eventually will fall "in line". ...

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Yes it could be out of plane Astronomers are reporting today the discovery of a planetary system way out of tilt, where the orbits of two planets are at a steep angle to each other. This surprising finding will impact theories of how multi-planet systems evolve, and it shows that some violent events can happen to disrupt planets' orbits after a planetary ...

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There was a report some time ago about a planetary system where there was no ecliptic plane: some planets were as off as 60 degrees from the orbital plane of the others (I don't remember the exact value by heart) That can happen if you have no medium to dissipate momentum.

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Beryllium is as exotic as it gets and it's the lightest usable metal. Due to its rarity only beryllium copper is made today but certainly better and lighter alloys are possible. Both for armor and for weapons. The downside is, beryllium dust is toxic. Staying with beryllium copper, the "extra hard" treated wire has 1415-1620 MPa tensile strength, it can be ...

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There is a problem with current solar panels: even here, on Earth they at most produce less energy for there lifespan (not in , but in kW*h) than it was total used to produce them (including extraction and transportation). Top solar panels are now at "1-to-1" zone or nearing it (if placed in California, not in Helsinki). But Mars gets times less solar ...

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There are many uncertain variables with your question. One being scale, how many solar cells are needed per year and at what efficiency? It is reasonable to presume that existing technology could be miniaturised sufficiently to enable small scale production of solar cells with fairly modest means. The technology is mature and well understood. Processes ...

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This is already happening See Unified Weapons Master Metal in the armour will be limited to a thin outer layer for appearances only with the inner layers being carbon fiber and impact foam. Sure it'd be nice to see more metal but really knights won't use that much and the sponsorship logos on the shield will sell more. At the end of the day you have two ...

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Depleted Uranium : for Flails, Two-Handed Hammers/Swords, and Shields For a swung weapon, mass is the reservoir in which the kinetic energy of a swing or a horse's charge is stored. This reserve of kinetic energy is what tries to foil potential energy reservoir of the target's yield strength times the strain. A high momentum hit will daze the other guy, ...

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If you don't want steel Aluminium and titanium are your best bets. For armor there are aluminum-steel alloys and titanium alloys. Making armor lighter is the biggest benefit you can gain. For more minor alloying components nickel improves both strength and corrosion resistance of steel. If you aren't restricted to just improving the metal parts of the ...

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I'm going to open the bidding with S1 Steel covered by ISO 4957 Rather than being cutting edge science, this is a commercial product. Specifically a shock resistant cold work tool steel. Medium carbon with tungsten and chromium. Ideal for weapons and likely armour as well. Specifically resistant to losing edge and deforming under repeated high impact while ...

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Brain Hog/Fog Well, you said "survive", and not "thrive", so run-of-the-mill starvation will solve your problem nicely. Others have observed that muscle mass has high BMR, which is why atrophying muscle is one of the first things the body does in response to starvation. But the single hands-down winner for specific energy consumption is the brain. It ...

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What you want to do is to decrease basal metabolic rate for humans. It is influenced by several factors, I just went through them one by one and came up with several ideas. Reduce physical activity Everyone goes to sleep About 30% of BMR comes from physical activity, thermoregulation and digestion: About 20% of one's energy expenditure comes from ...

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In short, you can either decrease the minimum energy the body needs to function through thyroid hormone reduction, or increase the amount of energy you get from breathing by artificially upping respiration rates. Anything that affects thyroid hormones will affect how much energy your body needs to function. For the thyroid. Medication: Thiamazole. Gene ...

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Cocaine is well known for having, among the short term effects, a reduction of the sense of hunger. I wasn't able to find the corresponding section in the English version of Wikipedia, so I quote the Italin version, which states Gli effetti neuropsichiatrici sono estremamente vari: Distorsione cognitiva e delle capacità recettive sensazione di ...

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GH1 gene If the GH1 gene has problems in a person, this person will likely be much shorter because of a lack of growth hormone. Smaller people consume fewer calories when idle (but more to walk the same distance as a tall person). So this could help in reducing global calorie intake if accompanied by other measures to diminish the need for physical effort (...

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Depends on how good of a chemist your time traveler is. While the purification methods on many of the needed materials were not discovered until the 1900s a good chemist, craftsman, and historian could go back further to the discovery of the ores he needs. To make the alloy you will need Iron, Titanium, Vanadium, and Aluminum: Iron has been around for ~...

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There's some ambiguity in the question - the title says "has the feedstock" but doesn't indicate whether that's ore, refined metals, or "can get to places where the ore can be found". Assuming it's the first option, ore: Probably Around 1900 AlexP's comment is valid, but if your time traveller has Future Wikipedia downloaded into his phone-analogue, all ...

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