Journey Into Space: Gravity, Orbits, and Collisions
Space Astronomy and Space
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Diameter: 3,000 miles across
Location: 1st planet from Sun
Distance from Sun: About 35 million miles
Average Surface Temperature: 330° Fahrenheit
Number of Moons: 0
Orbital Period: 88 Earth days
Characteristics: This planet’s orbit is the fastest.
Identity in Mythology: Mercury, the swift messenger of the Roman gods

(Image: Grolier Interactive)
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