Sometimes I wish I were at all captivated by space the way others in my life are! You can show me the most incredible photos of beautiful astronomical phenomenon, and I can't muster up anything stronger than "that's pretty cool."
I have little to no interest in space travel other than I think zero-g would be fun. I don't get anything out of the idea of seeing Saturn's rings in person that I haven't already gotten from seeing a picture of them. No sense of wonder when I look up at a night sky.
I also don't share as much of a passion for space and rocketry as some of our mutual friends, but one space image that's touched me more than any other is the Hubble Ultra-Deep Field, taken about 20 years ago.
Essentially, NASA pointed the Hubble telescope at a dark, lonely corner of space, and cranked the zoom to the maximum, focusing on an area with a width roughly one-tenth the diameter of the Moon as seen from Earth. They then took a three-month long exposure shot, to see what they could find deep in the darkness between the stars that we can see with our naked eyes.
In that dark, tiny section of the night sky, one-tenth the diameter of the Moon, they saw all of this:
There are few individual stars at this depth of field; the majority of the roughly ten thousand objects captured in the image are entire galaxies. Nothing has impressed upon me just how vast the universe more than this image. It is one thing to know "the universe, as far as we can tell, is infinite" and another to see just how much "as far as we can tell" actually is.
To see this, to realize that between any two stars I can see in the sky lay a million or more other galaxies, convinced me that life, even intelligent life, must exist somewhere else out there. It is simply impossible in a universe this vast, and this old, for life to have emerged exactly once.