Dynamic star chart for astronomical applications - is rotated by timepiece mechanism to provide star positions for each date and time

摘要

The dynamic star chart is coupled to a timepiece mechanism, so that it is continuously rotated in synchronism with the time of day and the variation in height and azimuth of the sky, to allow the position of each star to be determined for each specified date and time. A setting knob allows the star chart to be set manually to the required date and time, with stepped colouring of the twilight zones (3).