F-ckin Leap Seconds, how do they work?

Paul Graydon paul at paulgraydon.co.uk
Wed Jul 4 04:29:01 UTC 2012

On 7/3/2012 1:53 PM, Owen DeLong wrote:
> UTC (and the system clock) should not move backwards, but, rather they repeat
> second 59. UTC goes 58->59->00 most of the time, but during a leap second, it
> should go 58->59->59->00). It's not so much going backwards as dropping a chime.
If they do that, they're "doing it wrong", UTC and the system clock 
should go 58->59->60->00.  From the IERS bulletin announcing the leap 
second just past:

"A positive leap second will be introduced at the end of June 2012.
  The sequence of dates of the UTC second markers will be:		
                           2012 June 30,     23h 59m 59s
                           2012 June 30,     23h 59m 60s
                           2012 July  1,      0h  0m  0s"

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