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Some people call Earth the blue planet—and with good reason.
More than 70 percent of our planet is covered with water. That’s
what makes Earth so special. Living things couldn’t survive
without all that water.
Like Venus, Earth has a thick atmosphere. And below our
feet, the planet has four layers—the
crust
, the
mantle
, the outer
core
, and the inner core. The mantle contains hot,
liquid rock called magma. The
inner core and outer core are
made of metals.
Earth has something that
Venus and Mercury don’t: a
moon. It circles Earth once every
twenty-seven days. That’s just
about a month. A day on Earth
lasts twenty-four hours. And a year
on our planet has 365 days.
Home, Sweet
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