Or you can make your own…

And there is a book on the project (which has been active since 1999) which I'm sure I bought but seems to have walked.

Edited By John Haine on 22/02/2018 09:52:49

This one should work for more than 10,000 years and stays accurate to within 30 s:

**LINK**

Russell

Not wishing to rain on the parade but I suggest caution in predicting metals performance over a time span of more than a few hundred years. The metallurgical / crystalline structure of modern alloys has not been proven for more than about 200 years (projected performance is one thing – proven performance is another. ) We do have artifacts of very old metal objects in iron copper and bronze from thousands of years ago in Egypt and around Irag and Syria and Israel but no one could measure them accurately or do metallography at the time to compare to what it possible today – so those metals may have changed significantly in size, surface condition, and microstructure over the millenia – we have no way of knowing.

(BTW this is what really scares me about long term no leak storage of nuclear waste in steel or stainless steel containers here on Earth)

Environmental conditions could change significantly in 10,000 years and the HVAC plant to keep a particular room or chamber at stable environment today may not do so in even 100 years. This will have a big effect on the service life of metals particularly regarding corrosion in moving and mating parts.

Atomic decay clocks have predictably stable decay rates but I suspect the supporting electronic equipment in this type of clock – particle detector, A to D converter, LED display etc will have service life in hundreds of years max – maybe less – but not thousands of years. Any polymeric materials used (epoxies in PCB's, IC shells, LED housing acrylic) may not last even 100 years without degradation and dimensional changes. The gold in the electronics should be stable but the copper will probably corrode away in a few hundred years with normal atmospheric moisture. This already happens in 30 year old cars – the ones with first generation auto electronics.

Just food for thought, and my $0.02 worth.

Edited By Jeff Dayman on 22/02/2018 14:57:25

A lot of work has been done on the materials for this clock to make sure it lasts. It will be (is?) housed inside a mountain in a western US desert where it is very dry and the temperature range small – no HVAC needed or indeed possible. If you think of for example the Antikythera mechanism which is made of bronze and survived under the sea (though not in working order!) for 2000 years, something in a carefully selected benign environment stands some chance of survival. One fascinating detail is that the time will be reset to noon, adjusted to the equation of time, every day by a thermal mechanism actuated by the suns rays. The point of the whole project is to make people think about how you would design a complex machine that has to work for 10 millennia, rather than be thrown away in 18 months. A partial prototype was on show in the Science Museum in 2013.