Steve,
Some comments on your fine posting...
> But Essen claims for himself (in both this autobiography
> and in Metrologia
I found the Metrologia article interesting. I had heard
of 100 ms steps (leap tenth-seconds) but not the 50
ms steps.
Did you notice he appears to refer to a leap second
when he suggests "moving the minute marker along
by 1 second on a prearranged date, possibly 1 January
and 1 June". A scan of the Essen article is now at:
http://www.leapsecond.com/history/1968-Metrologia-v4-n4-Essen.pdf
> Knowing the tides is a specialist operation, and has always been.
> Knowing the phase of the moon is a specialist operation, and has been
> in western culture for over two millenia.
> What we are being told by the Time Lords is that, starting from a date
> in the near future, knowing when noon is will also be a specialist
> operation.
Isn't knowing when noon is already a specialist operation?
I mean, most people could tell you when noon is to within
an hour or two or three, but finer than that requires a far
amount of daily mental calculation, no?
Another observation is that our local newspaper always
prints Sun and Moon rise and set times. But not time
of noon. Why is this? Maybe it's just our paper (noon
implies sun and we don't see much of it here in Seattle).
Why is the instant of sunrise or sunset of popular value
while the high point of noon isn't. What does this suggest
about the risk of allowing noon to wander an hour over
the span of 1000 years?
> "Month" is entirely conventional in its meaning.
> "Year" is entirely conventional in its meaning.
> So soon "day" will be entirely conventional in its meaning.
Can you explain this more? I can see how Month
would be conventional, or even entirely conventional
but are year and day also such extreme cases?
It seems to me the popular understanding of a year
is accurate to +/-1 day. And the popular understanding
of noon is accurate to +/- 1 hour or two. Does that make
them "entirely conventional"?
> The trick will be to educate the general public that 12:00 means
> slightly less about where the sun is in longitude than the Gregorian
Sure, but it seems to me - regardless of the timezone,
regardless of daylight saving time, regardless of the
season, regardless of latitude, to the general public
12:00 means lunchtime (or their VCR got unplugged).
The sun doesn't have much say about it.
/tvb
http://www.LeapSecond.com
Received on Mon Jan 24 2005 - 00:59:12 PST