Have you ever wanted to dig a hole all the way through the center of the Earth to China?  Maybe you have a pen pal over there or something...  Maybe you just wanted to be the first one to do it.

Turns out that as soon as you dug a hole about 5 miles deep, you would be burnt to a crisp by all the heat!  No one has even been beyond the first layer of the Earth.  Guess you're going to have to stick to being pen pals...  or buy a plane ticket!

By using a variety of advanced techniques, scientists have been able to make a pretty good guess about what lies beneath the surface of our planet.  There are five main layers – the crust, the upper mantle, the mantle, the outer core, and the core.