noun
orrery
A mechanical model of the solar system that shows the relative positions and motions of the planets and moons.
科学博物館で太陽系儀を見学した。
I saw an orrery at the science museum.
A planetarium projects the night sky onto a dome, while an orrery is a physical mechanical model of the solar system.
Compound of 太陽系 (solar system) and 儀 (instrument, model). The term is a direct calque of the English 'orrery' or similar Western astronomical instrument names.