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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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Essential Advocacy

Our Advocacy Program provides each Society member a voice in the process.

Funding is critical. The more we have, the more effective we can be, translating into more missions, more science, and more exploration.



Beyond The Horizon, There's More To Explore!

Become a member of The Planetary Society and together we will create the future of space exploration.

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Space in Images

Pretty pictures and
awe-inspiring science.

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Let’s explore the cosmos together!

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