The ocean is blue because water absorbs colors in the red part of the light spectrum. Like a filter, this leaves behind colors in the blue part of the light spectrum for us to see. When sunlight hits ...

How many of the world's lakes have blue water, as opposed to green, brown or some other color? What does a lake's color say about its health, and what causes lake color to change? Scientists know a ...

Geologists discovered a new blue water spring at Yellowstone National Park that likely formed after a series of "mildly explosive events," the United States Geological Survey said. The hole is about ...