To the original post. Instead of asking what is, maybe you could ask what if? What if the sun emitted cold instead of heat? Well in our current understanding of modern physics, that would not be possible. In simple terms, the sun emits heat because it feeds on its own center of mass. Like a campfire, the embers glowing inside a long lit flame. The embers or soot will sustain their energy long after the flame is gone. Heat is the most radiant energy in our solar system. As I just discussed it is fed by the burning of its own mass. It is a challenge to wrap your mind around the sun emitting cold as a result of this concept. Regardless, In that dimension if the sun emitted cold instead of heat. Life as we know it could not exist. Further implicating, you would not have the possibility to ask this question.