The Earth’s inner core is incredibly tricky to study, since it’s buried beneath thousands of miles of rock. New seismic studies suggest that it’s not just a solid ball of iron, as has been assumed, ...

Though Earth's innermost core is solid, new research suggests that it hosts a lot of variation. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

A new analysis has found that Mercury has a solid inner core, just like Earth does. And Mercury’s core is just about the same size as our own planet’s. I’m biased here, but Mercury is an incredible, ...