[LEAPSECS] There's nothing strange about Washington, Mr. Carpenter!

Rob Seaman seaman at noao.edu
Thu Feb 3 10:40:30 EST 2011

Tony Finch wrote:

> If you have a good clock you can work out the equation of time. If your reference is a sundial you can set a bad clock to mean solar time using the equation of time.

An excellent exposition of why our civilization's fundamental time reference should be a big gaudy physical phenomenon shared by all, rather than an enigmatical ensemble of clockworks squirreled away in laboratory basements.

Gedanken: Let the power run out and the clocks run down. In fact, smash all the clocks on the planet. Shred all the calendars. Burn all the books - except for one copy of the Astronomical Almanac.

Result? Date and (solar) time could be recovered from simple observations of the Sun, Moon, and planets against the tabulated values. Meanwhile, the only possible way to recover TAI would be through reverse engineering from UTC.

TAI provides the steady rate. UT provides the zero point, charmingly mobile. The two work together.

In "The Day the Earth Stood Still", the Earth was in fact the one thing Klaatu didn't bring to a standstill.


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