A billion years may not sound young, but researchers estimating the age of the Earth’s core say it could be between 1 and 1.3 billion years old – which is at the lower end of previous estimates.

Related: How did Earth form? At the center of Earth is a solid iron inner core. The hot dense core has a radius of about 759 miles (1,221 kilometers) and a pressure of about 3.6 million ...

How far into the past can ice-core records go? Scientists have now identified regions in Antarctica they say could store information about Earth ... 3-km long, shorter than the 800,000-year-old ...