It consists of a terrestrial globe 1 which, upon rotation inscribed in a transparent sphere composed of two hemispheres 2, 3 of different colour which in turn oscillate with a path of 46 degree 50 minutes of arc, simulates the sequence of day/night and the progress through the seasons. The aforesaid oscillation is facilitated by two grooves 4, 5 of 23 degree 27 minutes of arc formed in each one of the hemispheres 2, 3. Said grooves 4, 5 are traversed by extensions 6 of the polar axis of the terrestrial globe 1. It has teaching and industrial applications. Provision is made for versions incorporating a circumscribed celestial sphere, with the use of a single one of the hemispheres and with modification of the system for anchoring the transparent sphere to the support frame. All versions have internal illumination.
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