[time-nuts] Why 9,192,631,770 ??
Poul-Henning Kamp
phk at phk.freebsd.dk
Wed May 9 05:43:51 UTC 2012
In message <F621A5241A5E4ACF82E70AA8CC48B714 at self6a5awnhg2m>, "Eric Lemmon" wri
tes:
>No, leap seconds have to do with the gradual slowing of the Earth's
>rotation, and nothing to do with Cesium.
Not quite true.
When they decided the 9,192,631,770 they did so with astronomical
observations which were half a century old. If they had used a
more up to date astronomical result, we would have had a lower
rate of leap seconds, essentially getting rid of the "one leap
second every 18 months" average value.
In the long term it doesn't make a difference of course, there
earths slowing down will dominate.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
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