Horological Meandering

dedestexhes
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new project: final posting

Hi all, Some time ago a posted some pictures about the work in progress of the orrery I had commissioned. Now after 4 months of waiting I can show you the final result. I must say I'm thrilled by it. The maker added some features specific to this orrery as he only makes one off's. Some info from the maker: All ratios of the movement are correct. All moons rotate around the planets.I have added Mercury following an elliptical path whilst rotating accurately whilst it does. Venus is shown rotating on its axis in retrograde. Uranus is shown with its North pole pointing away from the Sun and the moons orbiting in retrograde. As with all Orrerys it is not possible to accurately scale down the universe,its just to big. However all the planets orbit times are accurate (much better then 1%). The moons are a little more difficult to portray. For example the moons of Mars, Phobos and Deimos are shown orbiting in correct relationship to one another a ration of approx 4-1. If they were to rotate at a correct'scale speed' to Mars then the inner moon would be whizzing round at about 1500 rpm.( based on an average earth orbit time of 90 seconds) and so I have slowed them down to a more manageable speed. Some more details: The Orrey has 178 gears in total + one 73 tooth drive worm wheel and worm. One revolution of the handle is equal five earth days. ie 365/73=5. 73 revolutions of the handle is equal to one full Earth year. It requires 18082 turns of the handle to make Pluto complete one orbit of the Sun. Height of the Orrery from the bottom of the feet to the top of the Sun approx 14" or 270mm. Centre line of the Orrery to the end of the Pluto arm 560mm. Centre line of the Orrery to the end of the Neptune arm with sufficient clearance to allow rotation of the moons 540mm. The Orrery legs fit inside a circle of 15" or 390mm. Weight with arms attached 24 LBS or approx 11 kilos. Hope you enjoy the pictures (even if not high quality)!