The Tellurium developed by Vista Rasch demonstrates the Sun, Earth and the Moon in relation to our basic time units days, months, and years, and the correlating calendar systems.
The electromechanical model has a 3-meter diameter; the solar model is 23 centimeters, the Earth model 12, and the lunar model 4 centimeters in diameter. Additionally, the celestial sphere of the Northern hemisphere is reproduced.
The Tellurium shows the different periods of rotation and revolution of the celestial bodies relative to each other. One day - the time period of the Earth rotating once about its axis- is shown here in two seconds. For one orbit around the Earth, the Moon model takes about 59 seconds, which corresponds to the time period of one month. A year- the time for the Earth to complete one orbit around the Sun - is shown here in 730 seconds.
Two LED rings visualize the solar and the lunar year. Every day of the year corresponds to one LED in the model. As the lunar year is 11 days shorter than the solar year, only 354 LEDs are shown on the lunar ring, compared to 365 LEDs on the solar ring.