[time-nuts] Leap-second happens when...??

Magnus Danielson magnus at rubidium.dyndns.org
Sun Dec 28 01:17:12 UTC 2008


> : The first preference on which month to insert them is first to the June 
> : and December.
> : 
> : The second preference is on Mars and September.
> 
> I assume you mean 'May' here.

No. Read on. (spelt March incorrectly. sorry)

>  The standard additionally allows for
> leap seconds at the end of any month.  However, there's a lot of
> software out there that will be dodgy for the Secondary times, and not
> work at all for the others.

TF.460-4 says:

"A positive or negative leap-second should be the last second of a UTC 
month, but first preference should be given to the end of December and 
June, and second preference to the end of March and September."

There is an incorrect interpretation that only December and June are 
allowed. Another incorrect interpretation is that only March, June, 
September and December is allowed. Each month is allowed. There is only 
a preference towards the others. The flagging of upcoming leap second 
occuring in December already in July is ambiguous. Ah well.

Anyway, the TF.460-4 is very clear on it. May is allowed, but not preferred.

Cheers,
Magnus



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