Star of the Titans
Milky Way
The
Galaxy has this appearance because it is a disk-shaped
structure that is being viewed from inside. Earth is located
within the Galactic plane of this disk, around two thirds of
the way out from the center, on the inner edge of a spiral-shaped
concentration of gas and dust called the Orion–Cygnus Arm.
The Milky
Way is a barred spiral galaxy 100,000–120,000 light-years in
diameter containing 200–400 billion stars. The Galaxy is
estimated to contain at least as many planets, 10 billion of
which could be located in the habitable zone of their parent
star.
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