Fire is a chemical reaction known as oxidation, meaning it is the combination of oxygen with something. Oxygen is very reactive, thus why fire is so common.
Fire puts out heat and light, so does the sun, which is why we liken the sun to fire. However, there’s no fire in the sun in the sense of oxidation happening. There’s very little oxygen.
The main reaction is two hydrogen nuclei ramming together because of gravity and heat and fusing into a helium nucleus. This fusion releases mass amounts of energy, which come to us as heat and light from the sun. Eventually enough helium can get in the core to begin producing lithium, carbon, oxygen, and ultimately iron, in a process known as stellar nucleosynthesis. (Although oxygen is produced, it would never be able to oxidate anything, a star is simply too hot to allow compounds to exist.)
When the star has created large amounts of iron, it starts to hit a wall. Iron is very hard to fuse into heavier elements, and when it does it’s apparently an extremely violent reaction.
Eventually, enough iron builds up in the core that the star explodes in a supernova. The resulting explosion, if you can imagine an explosion taking literally years to progress, creates all the heavier elements known to exist.
Our star will not supernova. It is not the right type of star for that. It will become a red giant, then a nebula. Its core will remain the longest, as a white dwarf.
The core of the Sun is by now more than half helium, by the way. The heat it releases is energy, not fire, which transfers slowly up through the various layers and is finally released as photons.
Living things are adapted to specific range of wavelength of the light (which happens to overlap with the range of the Sun - strange, huh?). So yes, any light will do, provided it is in the correct range (e.g., pure red will be probably bad for both plants and sunbathing).
BTW, may I suggest Wikipedia? I heard they have more articles than these humble forums
Haha. Sorry, I considered that maybe you were being sarcastic, but I wasn’t sure. The interwebs are rubbish with communicating subtly. Someone needs to invent a sarcasm smilie.
