a question from national geographic!!

What is an armillary sphere?

An armillary sphere is a glabe made of movable, concentric rings that depict such things as horizon, meridian, equator, tropic, and polar circles. The earliest known complete armillary is attributed to the Greeks in the early second century A.D Ptolemy created one to promote his geocentric vision of the cosmos. In 1543, German mathematicion Caspar vogen constructed ptolomy’s theory. In the same year, Copernicus published his revolutionary treatise placing the sun at the center of the solar system. Afterward, Ptolemaic and Copernican spheres were exhibited together to display the differences between the two version of the cosmos.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s