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Solar System 101 | National Geographic
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- [Narrator] Our solar system is one
of over 500 known solar systems
in the entire Milky Way galaxy.
The solar system came into being
about 4.5 billion years ago, when a cloud
of interstellar gas and dust collapsed,
resulting in a solar nebula, a swirling disc
of material that collided to form the solar system.
The solar system is located
in the Milky Way's Orion star cluster.
Only 15% of stars in the galaxy host planetary systems,
and one of those stars is our own sun.
Revolving around the sun are eight planets.
The planets are divided into two categories,
based on their composition,
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