What were the three main initial sources of heat that kickstarted planetary differentiation?

Answer

Accretional Heating, Compression, and Radioactive Decay

The initial heat required for melting comes from the energy released during accretion, the heat generated by the immense weight compressing the interior, and the decay of short-lived radioactive isotopes.

What were the three main initial sources of heat that kickstarted planetary differentiation?
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