What could be out there may be beyond our imaginations.
I live in the country. I'd let my dog out about 4 am or so last fall and I was standing outside waiting for him to do his thing when something to my NE caught my eye. The sky was completely black. What appeared to be something flat, not a disk but more of a rectangular shape surrounded by a dull orange glow for lack of a better explanation was soundlessly moving slowly across the sky. As I stood and watched it pass almost overhead, it passed behind a big cottonwood tree in my yard and continued to slowly fly to the SW until it was out of sight. There was low cloud cover so whatever I saw wasn't very high. The wind was calm and there wasn't a sound the whole time this object was in view. It was in sight for maybe 15 seconds or so I'd estimate.
I have a background in aviation and studied the space program for two years in grad school, but whatever I saw that morning is something that I can't explain.