[LEAPSECS] [QUAR] Re: The Battle of Flodden Field

[Rob Seaman]

On Jan 9, 2011, at 1:10 AM, Poul-Henning Kamp wrote:


> In message <65E5B6C4-57C4-4232-9F2E-9AF20B921116 at noao.edu>, Rob Seaman writes:

> 

>> A proposal's "aims" should be explicitly stated.  If "coarse" adjustments are planned, they should be discussed.

> 

> The proposal contains:

> 

> 	The ITU Radiocommunication Assembly,

> 

> 	considering

> 

...

> 	g) the desirability of maintaining a relationship between

> 	a uniform time scale (UTC) and the time defined by the

> 	rotation of the Earth (UT1);

> 

> 	h) that the complexity of the variability of the Eartht's

> 	rotation currently limits the accuracy with which the

> 	difference between the two types of time scales can be

> 	predicted to a few tenths of a second one year in advance;

> 

> 	i) that the International Earth rotation and Reference

> 	system Service provides updated data relating the two time

> 	scales daily to users;


This asserts (implicitly and embedded in legalistic prose I've omitted) that no "adjustments", fine or coarse, are needed or will be applied.  Presumably indefinitely.

It also asserts that some other organization should notify "users" (all inhabitants of Earth) of the growing discrepancy between the to-be-redefined-UTC and actual Universal Time.  I presume that's a "should" as opposed to a "shall" since what authority does the ITU have over the IERS?

I'm glad to see the authors of the draft recognize that the uniform time scale they are seeking and the fundamental Earth orientation timescale are two distinct things.

My assertion is that for the particular purpose of civil timekeeping the underlying timescale is of the Earth orientation kind.  This draft asserts the opposite.

What is the ITU's definition of the word "day"?

Rob