Sep
01

From Earth to the Solar System: Yellowstone

Extreme color: What is causing the beautiful colors in this hot spring in Yellowstone National Park? Life, that’s what! Many microorganisms live in the pools there, and because the temperatures of the springs are so hot (most are well over 100˚F), they are called extremophiles (extreme-loving). They contain molecules that absorb the damaging rays of the Sun, protecting their DNA. Those same molecules are also pigments that cause the different colors we see. Different extremophiles thrive in different temperatures, so the color of a particular area is determined by which organisms are living in it. A veritable rainbow appears as the water temperature decreases as it flows further and further away from its superheated source. Image Credit: Darren Edwards


Posted: 1 September 2011
About the Author:

Alex di Giovanni is primarily responsible for "other duties as assigned" in the Office of Communications and External Affairs. She has been with the Smithsonian since 2006 and plans to be interred in the Smithson crypt.