... When I watch astronomy shows or go to NASA image galleries online I initially feel overwhelmed trying to wrap my mind around such incredible vastness. I just begin to grasp it when it just kind of falls apart leaving me kind of dissolute.
Yes, my very first experience like that was when I was young and trying to get a feeling for where the Universe might be. I remember realizing that if there is only one finite universe that the idea of "where is the universe", or "what is the universe in", is sort of undefined. Trying to visualize it or "grok" it gave me a kind of chill that was similar to a big hit of "loneliness" or something. I can still invoke the feeling when I think about it, but these days it is mitigated by my thinking that this is all in the hands of a loving God.
My second brush with the numinous came when studying physics in college and I began to realize that there were only a few mathematical constructs that seemed to describe pervasive phenomenon in the universe. For example, the wave equation shows up everywhere from sub-atomic phenomenon to galactic phenomenon. There are lots of examples like this. As you peel back layer after layer of physical phenomenon what you discover is an atonishingly beautiful and elegant system. Studying physics does not demystify the universe like some people might think. It simply reveals more and more amazing things that create more and more of a sense of awe.
Here is a good example: Consider that
Maxwell's Equations describe all electromagnetic phenomenon (light, radio waves, radiant heat, optics, etc) in the universe and they can fit on a matchbook cover. I don't know what is more amazing; that so few symbols can describe something so complex and pervasive, that something so universal and pervasive can be described by mathematics at all, or that a human being can actually understand something like E&M enough to conceive of such an elegant and comprehensive mathematical formulation.
You don't have to even understand any of the symbols to appreciate how amazing this is. I mean what the heck are we doing when we use mathematics to describe nature, and what does it say about us and nature when such a description works. Or put another way, why can math characterize the universe so well? And why can we do it? After all, we are basically just animated dirt, right?
Anyway, it was this kind of awe that brought me back to thinking there was a Creator. So yes, studying physics made a believer out of me.
You alluded to what is sometimes called
The Anthropic Principle, where it seems as if the universe was precisely tuned so as to be able to support organic life. I don't actually buy that as any kind of "proof of Design" because there are plenty of other naturalistic explanations for why that is so. What does it for me is the elegance and consistency of it all. For me its not a logical argument at all, but more like a feeling that this could only have been designed by a loving God at its most fundamental level.