"It's sort of a bizarre thing to think about. You have crystals within the outer core snowing down onto the inner core..."

The density of the metallic asteroid Psyche has mystified scientists, but a new theory points to molton iron as an explanation.

Understanding more about how a microorganism produces methane and carbon dioxide could help scientists cut greenhouse gases in the atmosphere.

"Iron from hydrothermal vents can well up, travel across hundreds of miles of open ocean, and allow phytoplankton to thrive in some very unexpected places."

Why some icebergs look emerald green instead of bright blue has mystified scientists for decades. Now they may have an answer.

Teen girls who donate blood are at greater risk for iron deficiency and anemia, but new regulations could make donating safer.

The new app doesn't need a blood test to tell if your hemoglobin levels are low, just an image of your fingernails.