It’s easy to forget, now that we’re no longer conducting atom bomb drills in our elementary schools, but just a few decades ago the nuclear arms race and its impact on the world was all too real. Though accounts of just how many nuclear explosions have occurred vary, this fascinating visualization from Orbital Mechanics features 2153 explosions, compiled using data from here and here. Atmospheric detonations are represented in red, underground in yellow, and underwater in blue. It's a fascinating new way to look at a dark piece of human history.