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This orrery, manufactured by the Trippensee Planetarium Company, is similar to those which were widely used in classrooms for teaching students about the motions, positions, and orbits of bodies in the solar system. This was a remarkably successful design and the Trippensee Company is still making instruments that are similar, in many ways, to the original that was patented in 1909. The manufacturer called this instrument a planetarium rather than an orrery.
USNO Master Clock Time
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