The Falls Within the Fall
The world's largest waterfall is actually underwater. At the Denmark Strait, the cold water from the Nordic Sea is denser where it meets the Irminger Sea's warmer water. When the water merges, the more dense water falls about two miles below the ocean's surface at roughly 123 million cubic feet per second.
Houston, I Can See my Shadow
Shadows are much, much darker and longer on the moon than they are on Earth. That's not exclusively reserved for your own personal shadow. Structures on the moon cast shadows that impede astronaut's abilities to function properly on the moon's surface. That's why astronauts have built-in flashlights in their helmets (you know, among other reasons).