Vintage Philips Planisphere for Latitude 42°N, USA, Europe, Japan.

My college aston class tool!

A planisphere is an astronomical instrument that consists of a star chart on a movable disk, used to show the visible stars for any sky region and time. It is a type of celestial sphere, representing the entire sky as seen from a particular latitude. Planispheres are valuable tools for amateur astronomers and educators, allowing them to navigate the night sky and identify constellations and prominent stars.

Philips, a well-known brand historically associated with electronics and lighting, also produced scientific instruments like this planisphere. This particular model is calibrated for a specific latitude (42°N), indicating its intended use in regions like the northern United States, southern Europe, and parts of Asia. The design features a rotating disk that aligns with a fixed star chart, enabling users to determine which stars are above the horizon at any given time of year and hour.