Clock: Orrery (planet display)

longnow.org > projects > clock > orrery

Completed on August 02005

The Orrery is an eight foot tall planetary display. It shows the relative position of the six human eye visible planets (Mercury through Saturn). The lower six layers are a mechanical binary calculation engine, each with a geneva output to a gear, which rotates a coresponding planet. Each layer is calculating a fraction of the planetary orbits to 28 bits of accuracy. Mercury takes about 88 days to make one revolution, Earth about 365 days, and Saturn takes over 50 years.

The Orrery is primarily made of monel (a nickel copper alloy), and stainless steel. The planet spheres are ground from natural stones that resemble each planet they represent The Sun is yellow Mexican calcite, Mercury is made from a meteorite, Venus from an orange calcite, Earth is a Chilean lapis, Mars is a Jasper, Jupiter is a banded sandstone, and Saturn a banded onyx.). The Orrery needs to perform one revolution of the calculation mechanism each 12 hours to keep the planets updated. Most of the large wheels and sliders revolve on a series of vee rollers that can be changed even when the parts are moving. All the bearings in the Orrery are designed to be 'hot swapped', meaning that the mechanism does not have to be taken apart to replace them.

You can see more about the Orrery in the November 02005 cover story from Discover Magazine.

The Orrery was conceptualized by Danny Hillis, project management and additional design by Alexander Rose, lead engineer was Paolo Salvagione, and lead machinist and fabricator was Christopher Rand. Other machinists include Erio Brown, Brian Roe, Mark Ribaud, Reason Bradley, General Precision, Oakland Machine Works, Jim Johnson, Brian Ford, Ebin Stromquist, and the base was fabricated by Seattle Solstice

All engineering for the Clock of the Long Now is done in Pro Engnineer courtesy of PTC. All CAM processing is done in GibbsCAM courtesy of Gibbs & Associates. The Long Now Foundation thanks them for their support.

Images

Pictures of the Orrery By Nicholas Chatfield-Taylor:

Jake Appelbaum Orrery Clock Image Orrery Clock Image

Orrery Close-ups By Jake Appelbaum at its first showing:

Jake Appelbaum Orrery Clock Image Orrery Clock Image Orrery Clock Image

 

Development

Images of an idea to have armillaries within armillaries representing a world network of mutliple clocks.

Orrery Clock Image Orrery Clock Image

Images of Pro E Models of the new adder mechanism.

Orrery Clock Image
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