earths layers

Why is the earth made up of layers?

The four main layers of the Earth are the crust, mantle, outer core, and the inner core. The planet Earth was formed about 4.5 billion years ago,

after the collapse of the supermassive gaseous body. As time moved on, the Earth cooled down and is still cooling, as of today.

As a result of the cooling process, denser materials like iron and sulfur sank to the inside of the Earth; whereas,

lighter materials like silicates and water came the surface.

we can understand the mantle is solid as the melting point is well above the actual temperature for it to melt  and that It's a little bit ductile (like a glacier) its able to move slowly over geological time

Five characteristics about earth

 

  1. Dipole magnetic field>deflects solar wind and protects from solar radiation

  2. Stratified atmosphere, mainly composed of nitrogen (n2) and oxygen (O2)

  3. Composed of minerals, glasses, melts, fluids and volatiles, all material left behind during birth of the solar system

  4. Layers: a thin silicate crust, a thick iron- & magnesium silicate mantle, and a thick metallic core

  5. Divided into a rigid outer lithosphere and a plastic/ductile asthenosphere

 

 

 

Earths magnetic field

 

Geodynamo : flow in the liquid iron outer core creates a magnetic field

 

For this to happen a planet must be:

  1. Rotating

  2. Have liquid outer core

  3. Be within the magnetic field of the sun
     

Magnetohydrodynamics! (combination of electrodynamics and hydrodynamics)