I hope they are able to figure this out, I would be interested to know how long the sun could burn on oil or kerosene. /s Legitimately though, assuming the sun

I hope they are able to figure this out, I would be interested to know how long the sun could burn on oil or kerosene. /s Legitimately though, assuming the sun is fake, how would one build an artificial sun? What could reasonably power it and give the impression to a planet within that it is real? Perhaps the problem could be even tougher if you're also trying to replicate the mass. The plot could be some advanced civilization planning to steal a near-by star and replace it with a fake, possibly to build a Dyson sphere around it to cypher off the energy. Could you fool the less-advanced civilization into thinking they still have a real star? (Ignoring the logistics of the actual swap.) A proposal for radiation: You could burn lots of fuel and radiate tonnes of energy out into space, but if you're only trying to fool a few planets, perhaps you could direct energy at them. I'm not entirely sure what you would have to do in order to make the light arrays appear correctly though. A proposal for mass: It seems as though a sustainable black hole could at least be as small as 3.8 times the mass of our sun [1] and a valid star could be > 1000 times the mass of our sun [2]. There's more than enough wiggle room there that you could have a small black hole within an outer shell, so the orbits could continue as normal. [1] https://www.space.com/5191-smallest-black-hole.html https://www.space.com/5191-smallest-black-hole.html [2] https://en.wikipedia.org/wiki/List_of_largest_known_stars https://en.wikipedia.org/wiki/List_of_largest_known_stars