The Elementary® planetariums (orreries) are available as lighted models (P-4020-000), or unlighted (P-4010-000) models.  These planetariums are suggested for use as a beginning model, and show individual concepts, one at a time. In this model, the Earth and moon are moved separately, by hand. The ladder chain and gear drive is used solely to keep the axis of the Earth pointed at a 23-1/2° angle, toward the North Star.

 

A few of the many concepts that can be demonstrated with this model are:

These are but a few of the many basic phenomena which can be explained and demonstrated with either of these models. An instruction book, Elementary Planetariums, is included.

 

Height: 12"

Arm length: 17"

Sun: 5 3/4"

Earth: 4"