I’ve been thinking about building a vertual orrery for a couple of years, but couldn’t quite imagine how it would work. Until, that is, l I saw Ken Condal’s videos: Building an Orrery. Orreries are mechanical models of celestial bodies, most often of the solar system, in this case the earth, moon, sun and the other planets out to Saturn. In this model the relative sizes of the planets and moon are accurate and their relative orbital periods are close to real. Except for the Earth, I used NASA photos of each body’s surface. The blue stationary gear is an earth year calendar showing the position of the earth and moon on any given day. My virtual model differs from Condal’s real one in some details; particularly I imagined the machine to be driven by a wind-up spring drive instead of a direct crank.
#orrery #Ken_Condal #Solar_system
