[LEAPSECS] Leap smear

[Gerard Ashton]

On 9/20/2011 5:53 AM, Poul-Henning Kamp wrote:

> B) Earth Orientation is not important at sub-half-hour precision.

I think a more precise statement of this is that earth orientation at 
sub-half-hour precision
does not seem to be a requirement for most recurring events that are 
scheduled at
a fixed civil time-of-day, such as bus schedules, time of arrival at 
work, time of shop
opening, and change-of-date for legal purposes (e.g. the date a document is
notarized).

Earth orientation is one factor in the time of sunrise and sunset, and 
that is important
at perhaps minute precision for many purposes, such as avoiding 
violation of laws
regarding turning on automobile headlights, and the taking of game. (Indeed,
white-tail deer are most active, and easiest to take, around sunrise and 
sunset,
and the legal taking hours begin near sunrise and end near sunset, so a 
minute
can be the difference can determine the success of a hunt.)

Part of a prudent engineering review before dropping leap seconds would be
a review of how all official sunset and sunrise tables, such as that at

http://www.eregulations.com/newyork/hunting/sunrisesunset/

to insure that the systematic change does not add to the lack of precision
due to applying a single table to a fairly large geographic area. (Such a
review would also clarify the table to indicate which variety of sunset
is intended, and whether the table represents a mandatory fictitious
sunrise/sunset, or a safe harbor that hunters have the option to
use instead of more precise location-specific calculations.)

Gerry Ashton