armillary sphere
noun1
An instrument consisting of graduated metal circles used to represent the motions of celestial bodies around the earth.
- Most of this bench is covered with tiles of Moorish design, but on the front each is stamped with an armillary sphere in which the axis is yellow, the lines of the equator and tropics green, and the rest blue. These one would certainly take to be of Dom Manoel's time, for the armillary sphere was his emblem, but they are said to be older.1908, Walter Crum Watson, Portuguese Architecture, page 24: