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Our Projects

Build an EarthDial

Specifications for an EarthDial
The measurements and necessary components for a standard EarthDial

How to Build an EarthDial
Step-by-step instructions (also available in PDF format or as a summary in Spanish)

How to Read a Sundial
What time is it?

EarthDial Glossary
Face, furniture, gnomon, gnomonicist, motto, style

EarthDial Calculator 
Calculates the locations of the lines on the face of the EarthDial for your latitude

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Planetary Defense

An asteroid or comet headed for Earth is the only large-scale natural disaster we can prevent. Working together to fund our Shoemaker NEO Grants for astronomers, we can help save the world.

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Beyond The Horizon, There's More To Explore!

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Space in Images

Pretty pictures and
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