How the Earth Was Made

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About 4.57 billion years ago, Our solar system is thought to have formed from a giant rotating cloud of gas and dust, known as a protoplanetary disc. The Sun formed at the center of the disc, and the planets gradually formed around the sun in a process known as accretion. 4.53 billion years ago, according to the “Giant Impact” hypothesis, the Moon formed as a result of a collision between Earth and a Mars-sized body called Theia. The impact caused a portion of the combined mantle of Earth and Theia to be expelled into space, eventually forming a Moon. 4.1-3.8 billion years ago, Impact craters on the Moon, many believe that the Earth endured a violent period of near-constant collisions with large asteroids and comets. About 4 billion years ago, the cooling of he Earth allowed the crust formation and the condensation of water present in the atmosphere, forming the Earth’s oceans. The atmospheric composition of the early Earth and the timing of crust and ocean formation have been topics of controversy within the scientific community. About 3.5 billion years ago, pillow-like rock formations called stromatolites, are formed as a byproduct of microbial life. During the formation of stromatolites, sheets of microbes, such as cyanobacteria, capture sedimentary particles. Successive layers of microbes and sediment result in the striated pattern of growth. We see form this that there was evidence that life evolved within a short billion years after Earth’s formation. The evolution of photosynthesis, which is believed to have occurred only once in Earth’s history, allowed the bacteria to covert light energy to chemical energy. The formation of oxygen molecules as a byproduct of photosynthesis eventually transformed the Earth’s atmosphere and paved the way for the growth in the bio diversity on the planet. About 2.0 billion years ago, geological evidence suggests that the
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