There's a lot more to Earth than meets the eye. Far from being just a roundish rock barreling through space, our planet is composed of several layers held together by intense forces of gravity.

Potential patches of Earth's ancient crust, sometimes called "sunken worlds," may have just been discovered deep within the mantle, thanks to a new way of mapping the inside of our planet.

Normalized concentrations of FL, DBT, and DBF (%).