Grand Prismatic Geyser

This is a photo of the Grand Prismatic Spring in Yellowstone’s Middle Geyser Basin. It’s absolutely unbelievable and very unique. I have never seen anything like it. It’s 250x380 feet and is 160 feet deep. In the center of the pool the water is 87° C (188° F)—too hot to support life. In the cooler water along the edges of the pool, however, colonies of thermophilic (heat-loving) cyano-bacteria and algae thrive. Yellow, orange, and red pigments are produced by the bacteria as a natural sunscreen. As a result, the pool displays a spectrum of colors from the bright blue of the center to the orange, red, and brown algal mats along the edges.