Philips Planisphere 51,5 N

Circular star finder for latitude 51.5 degrees north. Movable top disc can be turned into the right one hour angle so that the visible part of the starry sky can located. Brief explanation of the use of the star finder on the back. The planisphere can be used within a degree distance of +/- 10 degrees from 51.5 degrees N. Explanation only in English. Diameter 290 mm. Flexible plastic.