While most of us take the ground beneath our feet for granted, written within its complex layers, like the pages of a book, is Earth's history. Our history. Research shows there are little-known ...

Around 3,000 kilometers (1,864 miles) beneath our feet, there's a mysterious band of material called the D" layer, which has long fascinated scientists for its lumpiness. Thin in patches and thick ...

Some scientists think that Earth's inner core is actually made up of two similar but distinct layers. KATERYNA KON / SCIENCE PHOTO LIBRARY via Getty Images By studying seismic waves from earthquakes, ...