I remember going camping when I was 15. After everyone else fell asleep, I laid on my back under the clear open night sky and let my mind wander.
I first thought about planets in our solar system, then the interstellar medium, then other star systems with their own stars, planets and asteroid belts. I then "zoomed out" and thought about the Milky Way, then about other galaxies, spiral ones and starburst ones and irregular galaxies, and the void between them. I thought about nebulae and black holes. As time passed, I started to view Earth as just a planet, and our sun not as the Sun but as a star. Just one out of countless. I started to put myself in the shoes of an alien who lives on another planet - or maybe within interstellar clouds! - and tried to...
Then I stopped.
The reason I stopped was because I had the distinct feeling that my mind was about to break. As if I was about to run a buggy function, and if I pressed Enter to run it, it would throw an index out of bounds error and crash permanently. So I did the sane thing by pulling my sleeping bag over my head and falling asleep.