[ntp:questions] Leap second functional question

Unruh unruh-spam at physics.ubc.ca
Tue Feb 19 16:52:10 UTC 2008

Paul.Croome at softwareag.com writes:

>On Feb 18, 3:41 pm, Unruh <unruh-s... at physics.ubc.ca> wrote:

>> NTP time is UTC which assumes 86400 seconds in each and every [[year]] day.

>My understanding is the opposite: In the UTC time scale, the
>minute, hour, day, week are of variable duration, depending
>on the insertion or deletion of leap seconds.

>In the TAI time scale, the minute, hour, day, week are of
>constant duration.

No, in UTC all years are 86400 seconds, even if during that year a second
was added or subtracted. Ie, utc retains no memory of leap seconds. Thus a
year with a leap second added has 86400 UTC seconds but 86401 TAI seconds.
UTC simply erases that leap second from memory. It never existed.


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