Rotating astronomical chart for heaven and earth - has basic astronomical plate representing entire celestial sphere

摘要

In the middle of the celestial sphere there is the earth which is illuminated by the sun, represented by the intersection of its declination circle with the elliptic, and which is enlarged at will. On the earth its parallel circles and the meridian are used to connect a certain observation point of an arbitrary horizone of any point on the earth chronologically with the events on the celestial sphere by means of graduated circles. The basic astronomical plate is circular and cut out. Each of two astronomical charts represents the entire celestial sphere. Transparent plastic rotary discs may be used to achieve corrent orientation of variable objects as, for example, the solar planets.