Astrolabe is a model of the heavens. There were three types: linear astrolabe, of which no examples remain; spherical astrolabe, of which there is one extant example, and planispheric astrolabe which was the the dominant type. Astrolabes were closely connected with planispheres and relied on astrolabe projection. In Toledo a universal astrolabe was developed in the 12th century (Lamina universal and Saph‘a Arzachelis) which was later adapted to become a Gemma Frisius astrolabe. Rojas and La Hire produced other universal astrolabes.