Credits

• Page 03: Characteristics of the Sun

  ©2006 WGBH Educational Foundation. All rights reserved. Footage courtesy of NASA/Goddard Space Flight Center.

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• Page 04: Why Doesn't the Moon Fall Down?

  ©2006 WGBH Educational Foundation. All rights reserved. Footage courtesy of NASA/JPL-Caltech.

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• Page 08: Measuring Distance in the Solar System | NASA Planetary Sciences

  From "Scaling the Solar System"/NASA LaRC Office of Education; ©2013 WGBH Educational Foundation. All Rights Reserved.

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