Beneath Yellowstone’s thousands of square miles of mountains, pine trees, lakes, and rivers lies a volcanic system that has given rise to more than ten thousand thermal features across the park. The most striking of these is the Grand Prismatic Spring.

The word “prismatic” comes from the Greek stem “prisma,” meaning “separated or distributed as if by a prism.” The color separation in Grand Prismatic Spring results from a temperature gradient that gives life to different types of thermophiles. Orange, brown, and green microorganisms are found in the cooler waters around the outside of the spring, while the colorless and yellow thermophiles grow in higher temperatures. At almost 200°F, the center of the spring is too hot for most of these heat-lovers, leaving the clear water that reflects the deep cobalt blue we observe.

Photographing landscapes comes with its own challenges, but capturing images thousands of feet above a landscape presents a new set of factors to consider. There is no good way to prepare for reaching out from a helicopter traveling at 120 miles per hour and shooting straight down with the wind blasting your arms back towards you. A fast shutter speed, normally not critical for landscapes, becomes paramount. With temperatures significantly colder at altitude, gloves restrict the second-nature handling of the camera.

When we reached Grand Prismatic, the pilot tilted the nimble R-44 so we were leaning directly over the cauldron below. I knew I wanted to include people in the photograph, both to provide a sense of scale and to give a hint of realism to what is certainly an abstract scene. From this height, they are mere specks, dwarfed by nature’s masterpiece.  

My position directly overhead allowed for a perfectly flat view of the hot spring, revealing its true form that you can’t fully grasp from the ground. I returned with hundreds of images that afternoon, but one stood alone.