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Earth 101 | National Geographic
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- [Narrator] Earth, the only planet known to maintain life.
A product of scientific phenomena and sheer chance.
This blue speck in space holds the past,
present, and future, of our very existence.
(instrumental music)
Approximately 4.5 billion years ago,
the Earth formed from particles left over
from the creation of our sun.
Gravity drew these particles together
to form pebbles which then formed boulders,
and eventually, the Earth.
At its heart is a solid inner core
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