Eat a star

This is a hypothetical scenario for a story or game. If you’re here for science, you’re in the wrong subreddit.<br><br>To be clear, this is not about interstellar travel. This is not about wormholes or warp drives. This is not about terraforming or megastructures. It is what it says on the tin - eating a star.<br><br>Think about it. A star is an enormous nuclear power-source, and a nuclear plant is a premier power-source for us. So if we were to somehow harness a star’s power, could we harness it in a way that wouldn’t just vaporize the thing we’re using to do it? I know that stars are giant balls of gas and we can’t just plug in a power cable, but how close could we even get?<br><br>Would it be feasible to somehow smelt the core of a star into a solid metal? For example, could you theoretically smelt the core, attracting it with gravity or a magnetic field, and continue to do so until it becomes a nugget of star-stuff? For example, smelted from the core of the sun, a solid ball of metal with the sun’s mass would be roughly 197 kilograms. It would get hotter than the core of the sun, and it would remain that hot for a long time, giving you what is essentially a nuclear power source, or if you’re being really generous, a fusion plant.<br><br>If that were even possible, how feasible would it be to harness its power? You could place a conventional solar power farm around it, only instead of solar panels, you could have ones that can take super high temperatures. You could theoretically build an apartment complex around it, each room being a fusion reactor. <br><br>You could build a thermoelectric generator around it, taking the heat and turning it into power. Alright, so how hot does it need to be? Consider that the Earth is 149.6 million kilometers from the sun, and the sun’s core shoots out nuclear flames at 15 million degrees Celsius. So that’s 8.62 degrees Celsius for every kilometer you’re from it. So if you were to maintain a distance of 1.73 million kilometers, that’s already hot enough to vaporize steel. <br><br>To smelt the core into a solid metal, you would need to be an order of magnitude closer than that, so you’d be looking at the heat-equivalent of 8.62 degrees Celsius for a million kilometers. Let’s say for simplicity we have to smelt it to the point it’s as hot as the surface of the sun - 5,500 degrees Celsius. So then you would be a mere 640 kilometers away from the star-heart. Give or take a few orders of magnitude, this should give you a good idea of how hot it should be.<br><br>Would this smelt the metal nugget? Well, it’s still a solid piece of star, so the laws of thermodynamics still apply. It shouldn’t be as hot as a star burning in the vacuum of space, but it would still be incredibly hot. It would still be a smelted piece of star.<br><br>Would that star-smelt be able to smelt metal in turn? Absolutely. To melt metal, you need temperatures ranging from 450 degrees Celsius to melt tin to 1528 degrees Celsius to melt titanium. 5,500 degrees Celsius would melt any metal you put near it, as well as vaporize everything else.<br><br>So, what metal smelts at a temperature higher than 5,500 degrees Celsius? <br><br>Tungsten is a good candidate. It smelts at 3,422 degrees Celsius, so you’d need to make it hotter. Tungsten carbide has a smelting-point of around 2,600 degrees Celsius, so you’d need to make it hotter still. Tungsten boride smelts at a whopping 5,200 degrees Celsius, so you’d need to get it a mere 300 degrees hotter, at which point it will go from being the hardest metal known to man, to a puddle of goo.<br><br>So then, what metals are stronger than tungsten boride? Well, while I couldn’t find any naturally occurring ones that are stronger, I did find a few synthetic ones. There’s cubic boron nitride, which has a smelting-point of 4,000 degrees Celsius, but is four times as hard as tungsten boride. There’s lonsdaleite, which is 52% harder than tungsten boride and has a smelting-point of 1,700 degrees Celsius, and there’s boron nitride nanotubes, which smelt at 2,868 degrees Celsius and are eight times as hard as tungsten boride.<br><br>So if you want to smelt a star into a solid nugget of star-stuff, the best way to do it would be to smelt the core, or main nuclear furnace, of the star, to make it slightly hotter than the surface temperature of a star, and then somehow contain it using a metal that’s stronger than the heat will be. I’ve given you a few examples of metals that will do that, but you’ll have to work out how to use it. I recommend an apartment complex.<br><br>PS - This is a repost, as my first one was removed for being too similar to a post on r/askreddit.