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the solar system was a cloud of dust and gas known as a solar nebula. Gravity collapsed the material in on itself as it began to spin, forming the sun in the center of the nebula.
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The large dust cloud surrounding the newly born sun starts to clump with the help of gravity. The collisions of these clumps formed planets with immense amounts of heat.
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One theory of how the moon was formed is that a giant asteroid crashed into earth and it's debris started orbiting earth. Soon the debris from the collision clumped and formed the moon.
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The now relatively earth was beginning to cool. The Earth's surface — or crust — began to cool and stabilize, creating the solid surface with its rocky terrain. Clouds formed as the Earth began to cool, producing enormous volumes of rainwater from asteroids that formed the oceans.
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A shower of asteroid brought water to earth and metal to earth.
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Asteroid showered earth for somewhere between 20-200million years. near 3.7 billion years ago the heavy bombardment has end.ed
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Earth's liquid core formed long ago after earth started to cool and formed the crust and oceans covered earth. But earth's solid iron core that creates the magnetic field came much later. The exact time is still debatable but somewhere around 1.5b YA, the liquid iron churning at the heart of the planet froze and the cored formed.
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Earth's new crust grew rapidly, with about 70 percent of the crust formed by 3 billion years ago, researchers think. The earliest chemical markers of life also appeared with the first continents, about 3.8 billion years ago.
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Before photosynthesis evolved, Earth's atmosphere had no free oxygen (O2).[2] Photosynthetic prokaryotic organisms that produced O2 as a waste product lived long before the first build-up of free oxygen in the atmosphere,[3] perhaps as early as 3.5 billion years ago.
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Photosynthesis developed in plants causing oxygen to slowly increase in the atmosphere.
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The earliest form of life likely occurred around this time.
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the discovery of the zircon grains in Australia provides compelling evidence that the atmosphere and ocean formed before 4.4 billion years ago. The early atmosphere likely began as a region of escaping hydrogen and helium.