Mercury’s inner core tagged posts

Scientists have long known that Earth and Mercury have metallic cores. Like Earth, Mercury’s outer core is composed of liquid metal, but there have only been hints that Mercury’s innermost core is solid. Now, in a new study, scientists report evidence that Mercury’s inner core is indeed solid and that it is very nearly the same size as Earth’s solid inner core.

Some scientists compare Mercury to a cannonball because its metal core fills nearly 85% of the volume of the planet. This large core – huge compared to the other rocky planets in our solar system – has long been one of the most intriguing mysteries about Mercury...