Mechanical Tellurion model kit

Our mission: to spread knowledge of space and time by helping people visualize the movements of the planet we live on, and its closest satellite, the moon.

The Mechanical Tellurion is an accurate wooden model representation of our corner of the universe. A tellurion [also spelled tellurian, tellurium and sometimes called a loxocosm] is an ingenious mechanism that depicts the cosmic dance between Sun, Earth and Moon. The causes of day and night, the phases of the moon and the changing seasons are seen and understood according to the movements of this 3D puzzle. A tellurion [from the Latin tellus, meaning "earth"] is related to the orrery, which illustrates the relative positions and motions of the planets and moons in the solar system in a heliocentric model.

Build the beguiling DIY wooden model Tellurion, enjoy showing it to your family and friends, and you will all have a better understanding of the heavens, the seasons and the concept of time itself. Turn the handle to set the closely calibrated system of gears in motion. One turn of the handle = one rotation of the earth on its axis = one day. Point to a spot on Earth's surface, observe the spinning earth's position relative to the sun, and visualize sunrise and sunset, the passage of day into night. The Tellurion shows the phases of the moon are a function of the moon's position relative to the sun and earth.

At Ugears a rough approximation, or "close enough," isn't really our style. In representing the orbital periods of our planet and the moon, our design engineers have given the Mechanical Tellurion a sophisticated gear system [first worked out by Dutch mathematician Christiaan Huygens in the 17th century] to have the most accurate approximations possible in a wooden mechanism at this scale. The earth gearing has a 365.256 day orbital period, while the moon-earth gear system has an orbital period of 27.323, giving accuracies within one thousandth of a day.

This 3D representation of the earth's movements and its interplay with nearby celestial bodies will appeal to anyone interested in space, astronomy, skywatching, or to those wanting to understand, or teach a child, the basic natural phenomena that rule our lives: day/night, the seasons, the lunar cycle, and the construct of time.