Once upon a time, the composition of Earth’s inner core was a solved mystery.Once upon a time, in the 1930s and 1940s, the composition of Earth’s inner core was a solved mystery: Seismologists ...

The Earth’s core, for example, consists of about 90 percent iron by weight. Light elements such as sulphur, carbon, oxygen, and hydrogen make up a combined total of around 10 percent by weight.

One mystery we haven't solved yet is how the core has "frozen" solid from a molten liquid state in its past. "The Earth’s inner core was once liquid, but has turned solid over time.

As the Earth gradually cools, the inner core expands outwards at the surrounding iron-rich liquid “freezes”. That said, it is still extremely hot, at least 5,000 Kelvin (K) (4726.85°C).

Unlike the core, the mantle is mostly solid, and makes up most of the planet (84 percent of the Earth’s volume to be exact). Comparatively, the mantle also has less of a platinum-group-metal ...

Imagine Earth’s inner core — the dense center of our planet — as a heavy, metal ballerina. This iron-rich dancer is capable of pirouetting at ever-changing speeds.

Earth's inner core, the deepest part of our planet, is characterized by extremely high pressure and temperature, forcing the matter found there in a status somewhere between liquid and solid, a ...

Japanese scientists believe they have identified a mystery element that makes up part of the Earth's core. The ball at the centre of our planet is composed primarily of iron and nickel, which ...

While previous estimates have put the inner core at 500 million to 2 billion years old, a new study from an international team of scientists published in the journal "Nature" has found the Earth's ...