A very small planet
When I was about 8 or 9 years old, I got to go to a conference on soil mechanics. It's not as bad as it sounds; My dad has a PhD in soil mechanics, so I learned a lot, and the conference was in Orlando, so we visited Disney World, too. Plus, I got to meet an astronaut: Jack Schmitt, the last man on the moon.
I had been too young to know about Schmitt's political aspirations or his accomplishments outside of being a geologist and an astronaut, but having a chance to learn more about his accomplishments led me to find one that's very simple, but incredibly impressive. Schmitt created The Blue Marble.
As others have recorded, the Blue Marble is quite possibly the most-duplicated photograph of all time, and is inarguably one of the most famous images in popular culture. (For the geeks, there are some truly enormous high-resolution versions available.) A simple image search for "earth" yields almost infinite variations. We see it so often that, for me at least, it seems to register as another piece of clip art, or some kind of intricate logo, instead of an amazing and real picture.
It's not really about the photograph, of course. I offer a story about astronauts and engineering conferences as explanation, but the photo needs none. It leaves me struck that something as big as, well, the whole world can look fragile if you step back far enough to really look at it. And a work that took enormous resources to support, unbelievable imagination to create, and true courage to execute can seem downright ordinary once it becomes ubiquitous. There's probably something to be learned from that.