Science Faction Orrery
This astronomical model is a mixture of fact and fiction. As well as the Sun, Mercury, Venus and Earth/Moon, it includes 5 other bodies which as recently as 1990 have been observed by astronomers and sometimes authenticated, but which ultimately have proved to be non-existent.
The complex nature of the gearing results in the calculations of the rotational and revolutionary periods being similarly complicated; a table of calculations is included in the text for modellers seeking verification of the periods.
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