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    Space Force
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    Space Probes: Exploring Beyond Earth
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    6.1   | 
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    Space Tech
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    5.8   | 
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    Space Tools
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    4.6   | 
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    Space Tourists
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    6.0   | 
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    Space Words
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    Space Workers
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    6.1   | 
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    Stars
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    Stars, Galaxies, and the Milky Way
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    6.5   | 
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    Star Spotters: Telescopes and Observatories
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    6.2   | 
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    Sun
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    The Astronauts: Space Survival
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    6.0   | 
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    The Earth: Our home planet
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    5.7   | 
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    The Moon
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    4.0   | 
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    The Moon: Earth's Neighbor
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    5.5   | 
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    The Moon in a Month
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    2.5   | 
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    The Planets
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    3.8   | 
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    The Solar System, Meteors, and Comets
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    6.4   | 
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    The Space Shuttle
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    The Stars
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    3.7   | 
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    The Stars: Glowing Spheres in the Sky
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    5.4   | 
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    The Sun
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    6.0   | 
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    The Sun: Our local star
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    5.7   | 
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    The Universe, Black Holes, and the Big Bang
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    6.5   | 
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