>>5475485There are so many things wrong with this question that I don't even know where to begin.
>What would happen if a sun made of iceIf a star is made of ice it is by definition not a sun. Furthermore, any body of ice anywhere near the size of an actual star would collapse inwards from its own gravity.
>a normal, lava-made sunStars are not "lava-made", they are composed of plasma. Lava is molten rock, which again would collapse in on itself if it were in a star-sized sphere.
>ice-made sun’s temperature would be -1000 degrees of celsius This is physically impossible. The lowest possible temperature in celsius is -273.15, the temperature at which atoms are immobile.
>normal sun’s temperature +1000 degrees of celsius.For a star similar to our own sun, the surface temperature alone would be in excess of 6000 degrees celsius. However, since your description more or less falls within the range of a brown dwarf, I will give you the benefit of doubt and assume this is what you meant.
>Would their combined effects cancel each other out so that instead there would be only empty space or one 0-degree sun?A total conversion of matter to energy, or "empty space" would require annihilation, and both of your proposed "suns" are composed of matter. As for your second hypothesis, there are no known stars with surface temperatures less than around 400 degrees.
For the sake of attempting to answer your question I will consider a succession of large absolute zero ice bodies colliding with a typical 1000 degree celsius brown dwarf, such that the mass of ice and star is equal. The only result would be that the ice is broken down into hydrogen and oxygen and used as fuel for the brown dwarf's fusion, potentially making it hotter/brighter.
