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Asteroids and other cosmic objects fill our solar system, and Earth could be in the path of many of them. This Discovery Channel documentary reveals the planet's precarious position in the cosmos and what scientists are doing to prevent catastrophe.
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Episode 1
Sun, Mar 1, 200943 mins
30 million years after the birth of the Earth, a cataclysmic collision with a Mars-sized planet almost destroyed the planet completely. Instead, this chance collision formed the moon, triggering an extraordinary sequence of events that formed this unique planet teaming with life. As the vaporized Earth reels from the impact, the moon forms out of the dust and rock debris that gravitate around it. This world is completely inhospitable to life and yet remarkably, within a few billion years, life takes a hold. And all this is possible because of the moon. Mixing Earth's organic rich oceans with giant tides, slowing Earth's rotation and stabilising Earth's axis, the moon plays a vital role in progression of life.