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Subtopic: Solar System

Change grade range

Resource	Grade Level	Media Type
All Planet Sizes This illustration from the Lunar and Planetary Laboratory shows the approximate sizes of the planets relative to each other. Note that the planets are not shown at appropriate distances from the Sun.	3-12	JPEG Image
Galileo: Sun-Centered System In the early 1600s, most people believed that the Sun revolved around a stationary Earth. This video segment adapted from NOVA tells how Galileo proved that the Sun, not Earth, is at the center of our universe.	3-12	QuickTime Video
How Big Is Our Universe? This interactive resource from Harvard Smithsonian Center for Astrophysics uses images and activities to understand the scope and scale of our universe. Featured are technologies used by generations of explorers.	3-12	HTML Interactive
The Search for Another Earth This NASA video provides an overview of technology under development to explore the planets and stars outside our solar system. These will be the most sensitive instruments built to date.	3-12	Flash Video
What Is a Planet? This video segment, adapted from NOVA scienceNOW, presents the ongoing debate over the definition of a planet, including the status of Pluto.	3-12	QuickTime Video