Exploratour - Evolution of the Solar System
We've discussed the collapse of the solar nebula, planetismals sweeping up material, including the possibility of comets bringing volatiles into the inner solar system, the differentiation of the terrestrial planets, and we've discussed the T-Tauri phase of the Sun. Once the T-Tauri phase was complete, and the solar system was swept clean of material left over from the solar nebula, the planets can be considered to be officially "born". Now the Earths geologic "clock" starts to run. The first age of the Earth's history is called the Archean age. The Archean age started at this time.
Earth's surface was very hot and was still cooling. This means that there was no ocean on the Earth. We don't know for sure, but the rocks were probably all igneous rocks because they came out of volcanoes. Whatever the atmosphere there was prior to this time, at this point in history, the atmosphere of Earth began to change.
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