10,000 Year Clock

10,000 Year Clock

The following is a summary of this project’s websites.

10,000 Year Clock is a special Clock, designed to be a symbol, an icon for long-term thinking. It’s of monumental scale inside a mountain in West Texas. The father of the Clock is Danny Hillis. He’s been thinking about and working on the Clock since 1989. He wanted to build a Clock that ticks once a year, where the century hand advances once every 100 years, and the cuckoo comes out on the millennium. The vision was, and still is, to build a Clock that will keep time for the next 10,000 years. I’ve been helping Danny with the project for the last half dozen years. As I see it, humans are now technologically advanced enough that we can create not only extraordinary wonders but also civilization-scale problems. We’re likely to need more long-term thinking.

Visiting the Clock will take a commitment. The nearest airport is several hours away by car, and the foot trail to the Clock is rugged, rising almost 2,000 feet above the valley floor.

10kYClock_panoramaBuilding a Clock inside a remote mountain is a big task. Construction is under way, and we’re making progress every day.

Clock One – Raise Bore from The Long Now Foundation on Vimeo.

This is the way you’ll initially enter the series of tunnels and chambers that we’re creating within the mountain.

After many years of hard work and creative thinking, the final design and engineering of the Clock is nearly complete, and fabrication of the full-size Clock parts has begun.

Clock One: Winder & Main Differential from The Long Now Foundation on Vimeo.

The Clock’s chime generator creates a different bell ringing sequence each day for 10,000 years.

Carved into the mountain are five room-sized anniversary chambers: 1 year, 10 year, 100 year, 1,000 year, and 10,000 year anniversaries. The one year anniversary chamber is a special orrery. In addition to the planets and the Earth’s moon, it includes the interplanetary probes launched during the 20th century. The Clock will activate and run the orrery once a year on a pre-determined date at solar noon. We aren’t planning to build the animations for the 100, 1,000, and 10,000 year anniversary chambers, but will instead leave those to future generations.

We are providing a mechanical interface into those chambers that provides those future builders with power and the correct Clock triggering events. We do intend to build the animation for the 10 year anniversary chamber, but haven’t decided what it will be yet. If you have an interesting idea for the 10 year anniversary chamber, please feel free to email it to [email protected], and we’ll add it to the mix of ideas.

This is a really big project in multiple ways, and there are many partners who are helping make it a reality.

 Prototype 1

Completed on December 31st 01999

ClockAllWht290pxThis first prototype of the 10,000 Year Clock is currently on loan to the Science Museum of London, and can be seen as the final piece in the “Making of the Modern World” exhibit. This prototype began to tick on December 31, 01999 after an almost three year research and design effort. Following lead designer Danny Hillis, the team included project manager and designer Alexander Rose, mechanical engineer Liz Woods, horologist David Munro, and lead machinists Chris Rand and Erio Brown.

Power for the Clock comes from the two helical weight drives on either side of the Clock. The timing for the Clock is generated both by a torsional pendulum, with a one minute period, and by a Solar Synchronizer that re-calibrates the Clock to solar noon on any sunny day. To correct from solar time to the absolute time of the pendulum there is a specialEquation of Time Cam. The display on the Clock is made of two elements; the Serial Bit Adders and the dials. The Adders convert the timing generated from the pendulum, using their binary mechanical system, to changes in the Clock’s dials. The six dials represent the year, century, horizons, sun position, lunar phase, and the stars of the night sky.

The Clock was primarily designed by Danny Hillis, additional design work and project management by Alexander Rose. Engineering and part drawings were done by Elizabeth Woods. The Escapement and movement were designed and built by David Munro and General Precision Corp. Almost all other Clock parts were machined and assembled at Rand Machine Works.

All engineering for the Clock of the Long Now is done in Pro Engineer courtesy of PTC. The Long Now Foundation thanks them for their support.

Starting from the outside, on the right side of the dial viewed through a gold “window”indicator is the Gregorian year in 5 digits. This would read “02009” currently, and is made up of two rings, one showing the century or the “020” part, and the other adjacent outer ring with the “09” year part.

Inside of that is the gold colored sun ring that shows the current position of the sun in the sky over the course of a roughly 24 hour solar day. The moon is also rotating at the same rate, and is shown in its current phase (divided into 32 steps) through an opening. The sun and moon are interrupted in the lower half of the dial by the horizon indicators that show sun and moon rise/set. (These horizon indicators move throughout the year and can be set for a given northern latitude as far south as LA and as far north as London.)

At the center is the black domed display of the night sky overlaid by what is traditionally called a rete. The rete has indicators that show the range of night sky visible from upper and lower latitudes as well as some pointers that point to the celestial pole (currently very close the “North Star” or Polaris). This domed night sky is actually set on a 23 degree angle behind the face as it has to rotate on that angle roughly once every 26,000 years as the earth precesses on its axis.

Further down inside the clock is also a “mundane dial” that shows normal 12hr clock time, this is mainly a debugging device to be sure it is accurate. Also near this dial is the Equation of Time Cam which allows for the clock to be adjusted to solar time even though it is keeping absolute time.


If you are interested in visiting the Clock when it is complete (many years into the future), please subscribe to Clock Interest by emailing a blank message to [email protected].

Thanks for your interest in the Clock!
Jeff Bezos

Jeff Bezos discusses the 10,000 Year Clock from The Long Now Foundation on Vimeo.


Completed on August 02005

10kClock_OrreryThe 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 that rotates a corresponding 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 29.7 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 composed of meteorite; Venus is orange calcite; Earth is Chilean lapis; Mars is Jasper; Jupiter is banded sandstone; and Saturn is banded onyx. The Orrery needs to perform one revolution of the calculation-mechanism every 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”, which means that the mechanism does not have to be taken apart to replace them.

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  1. Starheater says

    Well, what do you say!!! I’m surprised that man can waste is time to make something that would not even last a century, why? Because the Earth is more and more unstable, a little earthquacke and boom, the clock is in pieces. I would not invest money in that project, if it were a clock that was station on a huge mountain, and the clock would be seen miles and miles around it will be helpfull in a way, right now, this is just a gadget that is not indispendable.


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