Yellowstone’s Grand Prismatic is named for its brilliant colouration. The colour spectrum that ranges from deep blue to burnt red is the product of trillions of thermophiles, or bacterial microorganisms, which flourish in hot waters. Different temperatures determine the hue, and the center of the pool is sterile due to extreme heat (70 °C or 160 °F) leaving the intrinsic blue color of water.

Picture by Werner Van Steen/Getty


Untitled by Gary Parker