The internal structures of the terrestrial planets

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The origin of planets

Lithosphere-asthensosphere-core

How do we know?

Xenoliths (mening strange rocks) are brought up from depths during volcanic erruptions

Mean density of the Earth can be calculated

Sesimic evidence

P (longitudinal) and s (transverse waves) can be measured from opposite sides of the planet. P waves travel through everything, s waves only solids. S waves can not get through the core

Earth has a magnetic field which shouldn't be possible as there is no SOLID above 1200 degrees with magnetic properties. The core must then be partially liquid.

Condensation of the solar nebula

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Accretion process begins

Formation of planetesimals

Accretion of planetary embryos

Impact of planetary embryos

Differentiation of planetary embryos

Heating a planet

Tidal heating

Radiogenic heating

Primodial heat

Resurfacing

Impacts on a planet are still common. Earth recycles the crust with volcanic action.