[LEAPSECS] Time on time
hmurray at megapathdsl.net
Wed Nov 30 13:45:21 EST 2011
> Speaking of time, what sort of time is the Long Now clock keeping, anyway?
> Solar, atomic, or something else entirely?
Solar. It's all mechanical. No electronics.
> Hillis concluded that no single source of timing could meet the
> requirements. As a compromise the clock will use an unreliable but accurate
> timer to adjust an inaccurate but reliable timer, creating a phase-locked
> In the current design, a slow mechanical oscillator, based on a torsional
> pendulum, keeps time inaccurately, but reliably. At noon the light from the
> Sun, a timer that is accurate but (due to weather) unreliable, is
> concentrated on a segment of metal through a lens. The metal buckles and the
> buckling force resets the clock to noon. The combination can, in principle,
> provide both reliability and long-term accuracy.
These are my opinions, not necessarily my employer's. I hate spam.
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