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Accretion
Around 4.56 billion years ago the solar nebula had nothing but cloud and dust. Eventually gravity caused the initial rotation motion to accelerate, and the sun was formed. With the sun, other materials clumped up, smaller thing came together with gravity and became bigger. The solar wind swept away lighter materials resulting in terrestrial worlds like Earth. The deepest layer or the core is made of solid iron and this results in the Earth's magnetic field. -
Planetary accretion caused the Earth to be extremely hot. At one point the Earth was completely covered lava. Gradually the Earth started to cool and took billions of years to cool to its current state.
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When Earth was formed it took a few hundred thousand years for the moon to be formed. Scientists aren't sure how the moon is formed, but a popular theory is that the moon is the result of meteor hitting the surface of Earth and the remains of those materials forming a bigger planet.
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Around 4 to 3.8 billion years ago scientists believed that there was a period of time where the Earth and other planets. However the craters and other records of this event were lost by the constant erosion that occurs on Earth.