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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Modern Antikythera mechanism for solar eclipses
From: Ken Muldrew
Date: 2025 Apr 1, 18:30 -0700
From: Ken Muldrew
Date: 2025 Apr 1, 18:30 -0700
In his book, Revolutions, Janvier designed a Ptolemaic orrery (he claims to have built it but the gear ratios are wrong, so that seems unlikely). It's a clever design to include epicycles, but without the dual-gear arrangement found in the Antikythera mechanism to simulate elliptical orbits, some of the planets build up a pretty large deviation rather quickly. Here is a sketch from the book:
Ken Muldrew.
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