Device for locating the coordinates of a star on a planisphere portion

摘要

The invention relates to a device making it possible clearly to locate on a planisphere portion the azimuth and elevation of a star or a planet seen by an observer situated at a determined point on the globe and situated approximately between latitudes 35 DEG and 50 DEG North. It consists of an opaque rule resting on a wooden support, having a horizontal rebate, in which there slides a transparent equitorial card. A removable device fixed onto the wooden support makes it possible to flip over the equitorial card a transparent table provided with determined azimuthal curves making it possible directly to read the azimuth of the stars; the elevation is measured from the latitude scale of the equitorial card with a pair of dividers. The device according to the invention is in particular intended to people performing celestial navigation or observation. <IMAGE>