ES11805U - Celestial map provided with a device for the determination of the visible field at any moment from a predetermined point of view of the earth. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

A celestial map provided with a device for the determination of the visible field at any moment from a predetermined point on the Earth, consisting essentially of a fixed plate on which a circular disk on which it is represented can rotate freely on its axis. in a graphic, word or both way, the field visible in the course of twenty-four hours from the point for which the map has been calculated, this disk being provided in its periphery of a series of twelve divisions with the correlative indication of the months of the year, subdivided eventually into days or other fractions of time, whose divisions may be coincided at will with others indicated on the surface of the fixed plate that is contiguous to said disc, which are in number twenty-four, corresponding correlatively to the hours of the day, and may be subdivided in turn into other minor fractions of time, also figuring, assembled the fixed part of the map, a frame whose contour corresponds to the horizon line, so that the inner disk is arranged in its corresponding relative position with respect to the fixed disk, depending on the month, day and hour - and possibly with fractions of inferior time- the part of the map that is limited by said frame will represent exactly the visible field of the celestial vault at that moment. (Machine-translation by Google Translate, not legally binding)