[LEAPSECS] ITU-R SG7 to consider UTC on October 4

[Rob Seaman]

On Aug 4, 2010, at 10:30 AM, Steve Allen wrote:


> According to the ITU-R the next meeting of SG7 will happen in Geneva  

> on

> 2010-10-04 and 2010-10-12.


Makes one wonder what they'll do with the intercalary week in between...


> Timofeev has released a questionnaire to the delegations along with

> instructions that SG7 should only consider technical issues.

> Technical issues would mean the draft is to return to WP7A.

> Other-then-technical issues are to be referred to the

> Radiocommunication Assembly.


Proper system engineering practices do not artificially separate  
requirements into technical versus other-than-technical bins.  Some  
technical requirements are non-quantitative.  Many "other"  
requirements are eminently quantitative.  A trade-off requires  
building figures-of-merit for all requirements and evaluating  
different schemes for combining and contrasting the quantitative  
scores and the sensitivity of different issues to various parameters.

By all means debate the issues - although does the Radiocommunication  
Assembly have a broad enough mandate to appropriately address the  
issues?  However, don't pretend that only real engineers can properly  
understand technical issues, while "other-than-technical" issues are  
some mash-up of trivial politics.


>    Do you support maintaining the current arrangement of linking UT1

>    and UTC (to provide a celestial time reference)?


Yes.  The current standard is viable for centuries, providing copious  
time to discuss options outside the current politicized process.


>    Do you have any technical difficulty in introducing leap second

>    today?


No.  The alternative would cause more trouble than it naively claims  
to circumvent.


>    Would you support the revision of Recommendation ITU-R TF.460-6?


No.  And TF.460-6 doesn't resolve the underlying geophysical issue or  
provide a future standards path to make the inevitable much larger and  
more intrusive adjustments to civil timekeeping that will be needed.


>    If it is agreed to eliminate leap second within 5 years after

>    approval of the revision of Recommendation ITU-R TF.460-6, would

>    that create technical difficulties for your administration?


Yes.


> The US draft answers from USWP7A Chairman Wayne Hanson are

>

>    no

>    yes

>    yes

>    no


USWP7A clearly doesn't represent the interests of astronomers or of  
general civil timekeeping.

Civil timekeeping is layered on mean solar time - a constant offset  
from the underlying sidereal period.  Pretending otherwise is naive.   
Those professionals who need a timescale without leap seconds have  
numerous options to choose from.  Leave UTC alone.  UTC without leap  
seconds would no longer be a flavor of Universal Time.

Rob Seaman
National Optical Astronomy Observatory