Navigational triangle
The navigational or PZX triangle is a term used in Astro-Navigation, or Celestial Navigation, and its solution can give you your position anywhere (more or less) on the globe. The sky is described as a Celestial Sphere with a North and South Pole corresponding to our own North and South Pole. Conveniently, the 'Pole Star' lies (more or less) at the North Pole of the Celestial Sphere.