"Who laid the foundations of the earth, that it should not be removed for ever?" (Psalms 104:9)
Christian thinking seems to mesh maybe a bit too well with a kind of Theological Foundationalism.
You will notice that in the above verse such thinking can be thoroughly inappropriate. There is no "foundation" (in any ordinary sense of the word) to the Earth. (Worse than that for this verse, we also know that the Earth moves!)
As nice as it might seem to be, why should we expect there to exist firm answers to the questions you've posed? Like the verse above, are you asking sensible questions?
Also read the rest of Psalms 104; I'd be really curious how you mesh that with our scientific understanding of these things. The sensibility of the rest of the chapter doesn't look much better.
Do you know if something is hot enough, or sharp enough, to hurt you? Do you know whether you like surrounding temps to be closer to 70 than 114, or -10? Do you eat when you fell hunger, seek kindness? Then why oh why are you wasting your precious Only days on this?