Origins: Earth Is Born/How Life Began
This episode shows that ancient cataclysms made our planet what it is today. Ironically, says Neil deGrasse Tyson, "Earth became a hospitable planet only after a series of devastating disasters in its early years." Chief among these was a titanic collision between Earth and a Mars-sized object, an impact so immense that it obliterated the colliding object and part of the Earth itself to create a dense ring of orbiting material that eventually collected into the moon. The collision tilted Earth's axis at an angle of 23.5 degrees – enough to cause the seasons. Other milestones in this eventful era include the formation of continental crust and the precipitation of water out of a hellish atmosphere. All of these events happened in a remarkably short period of time, perhaps in the first few hundred million years of Earth's 4.5-billion-year history. This new picture of our planet's formative era implies that Earth may have reached a habitable stage much earlier than previously thought.
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CC - Closed Caption
HD - High Definition
16:9 - Anamorphic Widescreen
LTR - Letterbox
DVI - Descriptive Video Information for the visually impaired
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