Pevaquark, I enjoy your expositions and you are providing some great explanations here on Genesis 1. However, I'd like to make one small correction concerning a claim that Bill Nye the Science Guy also makes in his lectures:
There is no lexicographic rule of any sort, neither in English nor in Hebrew, which says that a "light" must emit light of its own generation. (And even if such a rule existed in English, you couldn't automatically assume that the same semantic fields and distinctions applied to the original Hebrew word.)
Indeed, even a quick look at an English lexicon would show that the English noun light does not specify that the light comes from what a physicist might call a "primary light source" rather than a secondary one. Light generation is not the focus.
For example, one of the meanings of light is a window or window pane. That English usage dates back many centuries. Not only do we see that definition in the compound word skylight, it also arises when one visits a building supply company to buy or special order a door. When I ordered a new front door for my house, the first thing the clerk asked me was "How many lights?" He wasn't asking me how many light-bulbs would be attached to my door. He was asking how many window panes I wanted in the door in order to help bring sunlight indoors.
Thus, the fact that the sun produces its own light by means of the fusion of hydrogen atoms while the moon is a reflector of sunlight is irrelevant to both the English word for light and its Hebrew equivalent. Both the sun and the moon are lights because they illuminate the earth. How they do it is irrelevant to the word light and I doubt that the average Hebrew gave it any more thought than the average hunter, farmer, or jogger today.
By the way, TV and movie production crews use the word light with similar disregard for its source. Thus, on an outdoor film set some directors will yell to a gaffer, "Get me a light!" In a night shoot that will probably call for an electric light of some sort. But in the daytime, someone will probably grab a 4x4 or 4x8 reflective panel that helps increase the lumens reading when filming under the shade of trees. A light illuminates without regard for whether or not the object called a light is a generator, transmitter, or a reflector of light.
I've long been curious how this criticism of Genesis 1, day 4, got started. I've wondered if it first appeared in some language where the alleged primary/secondary light distinction was actually valid (even though it never was valid in ancient Hebrew.)