Cross-section of the Earth (left) and the exoplanet Kepler-138 d (right). ... These water layers make up more than 50% of its volume, or a depth of about 2000 km. The Earth, ...

An artist's rendition of a cross-section of Earth. The innermost layer, the inner core, is a 1,500-mile-wide ball of iron. CHRISTOPH BURGSTEDT / SCIENCE PHOTO LIBRARY via Getty Images ...

Earth is made up of several layers: the lithosphere, asthenosphere, lower mantle (also known as mesospheric mantle), outer core and inner core.

Below the mantle is the Earth's core, which has an inner and outer section. The outer core extends for around 1,400 miles and mostly consists of liquid iron and nickel.

A cross section of Earth. Our planet consists of several layers: a solid inner core, a liquid outer core, the mantle, and finally, the crust. forplayday/Getty ...

A global race is on to drill for the oldest known layers of Antarctic ice so researchers can peer back in time to a warmer climate to better understand the planet’s hotter future Deep in ...