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The solar system began as a rotating cloud of stardust (a cloud made up of hydrogen, helium, and dust). Supernova, nearby star, exploded and sent shock waves through the cloud, and caused it to collapse.
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Between 0 and 100,000 years after the solar system formed, our cloud is flattened into a swirling disk. A protostar forms in the center. Deep within the disk, clumps of dust are heated into chondrules (molten rock). These molten rocks clump together and grow into asteroids and planetesimals, eventually becoming planet embryos.
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An asteroid the size of Mars smashed into Earth. The huge amount of energy from the impact melted both the Earth and the asteroid. Material from both Earth and the asteroid was thrown out into orbit, which over time, combined to form our Moon. The collision happened about 70 million years after Earth formed.
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Different materials in a region of space collided and made a planet. All of the collisions caused Earth to heat up, which melted rock and metal. The molten material separated into layers– gravity pulled the denser material into the center, and the lighter elements rose to the surface.
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Between 100 million and 600 million years after the solar system formed, Pluto-like asteroids crashed into Earth and other planets, and deposited metals to the surfaces of these planets.
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Between 600 million and 800 million years after the solar system first formed. Jupiter and Saturn migrated towards the Sun, creating ripples in the asteroid belt and clearing out many smaller rocks. During this, comets carrying water hit Earth and created the existence of water.
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About 1.6 billion years after the Sun was formed, Earth gradually cooled down and the heat in the Earth's core tried to escape. As heat tried to escape, it broke up sections of the earth’s crust and created tectonic plates (continents) and magnetic fields.