# [ntp:questions] Leap second to be introduced in June

Mike S mikes at flatsurface.com
Mon Jan 19 12:15:39 UTC 2015

```On 1/19/2015 2:42 AM, William Unruh wrote:

> I quoted from the document you yourself pointed me at. TAI is
> continuous. UTC differes from TAI by and interger number of seconds, and
> that integer changes when a leap second occurs. If x is continous x-n
> where n changes at some time, is NOT continuous.

You clearly misunderstood TF.460, because you still have it wrong. There
is no discontinuity, the two scales merely count time differently. This
is how the time of the next leap second will be enumerated in each:

UTC                       TAI
2015/Jun/30/23:59:58      2015/Jul/1/00:00:33 (nb:35 second delta)
2015/Jun/30/23:59:59      2015/Jul/1/00:00:34
2015/Jun/30/23:59:60      2015/Jul/1/00:00:35
2015/Jul/01/00:00:00      2015/Jul/1/00:00:36
2015/Jul/01/00:00:01      2015/Jul/1/00:00:37 (nb:36 second delta)

Now, why don't you think a bit, then tell us where you think the
discontinuity is in UTC? Hint: if you think there is a discontinuity,
keep thinking.
```