Orrery at the Maryland Science Center

I have long been fascinated by orreries.  An orrery is a mechanical model of the solar system showing the relative movements of the planets around the sun.  Often used to calculate celestial events like eclipses, they were sometimes built around a clockwork mechanism so they could be wound up and, when let loose, the planets would revolve around the sun until the spring wound down and everything stopped.  Hmmm, there might be a metaphor in there somewhere.

Orreries have been around since at least the early 1700s, when one was presented to the Earl of Orrery, hence the name.  However, the remains of an orrery-like device were found in a shipwreck off a Greek island dating back to c. 125 BC.  The device was, incidentally, heliocentric.  Take that, Copernicus.

This orrery is on display at the Maryland Science Center in Baltimore, MD.  Well worth a day-trip to Baltimore's Inner Harbor district, the Science Center is full of interactive displays that will educate and entertain kids of all ages.