“The cosmos is also within us, we're made of star-stuff. We are a way for the cosmos to know itself.” - Carl Sagan

Compared to the Sun, how big is the Earth? What is a scale model and how does it help us understand the size of things? In this episode of STEM in 30, we'll walk you through the size of things that are impossible to measure in inches and feet. We'll show you how to calculate the circumference of the Earth using shadows and math. We'll even show you how we know that the Earth is round.

Learning Standards:

  • NGSS: MS-ESS1-3 Earth's Place in the Universe: Analyze and interpret data to determine scale properties of objects in the solar system.

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About STEM in 30

STEM in 30 is an Emmy-nominated program for middle school students produced by the Smithsonian’s National Air and Space Museum. These 30 minute episodes are great for classroom use. New episodes are released every month, featuring hands-on activities, explanations of aviation and space topics aligned with national standards, and interviews with experts from the Museum and beyond.

STEM in 30 is made possible by Boeing, Hexcel, and Safran.