Its spinning, molten, liquid, iron core.
Mariana's Trench
STRATOSPHERE
the layer of rock that comprises 67% of earths mass
half of earths layer
The earth thinnest layer is the crust.
The crust is the thinnest layer of the Earth.
Actually, the Troposphere Layer can be considered as Earth's first protective layer, because its well-the atmosphere's first layer. You can think of it that way to remember which is Earths first layer.
The earths crust is a part of the outermost layer.
mesosphere
troposphere
The layer below the earth's outer layer is mesosphere. It is the 3rd layer.
Crust