Re: Leap Seconds

[Joseph P Vlietstra <joevl@concentric.net>]

Paul Storm wrote:
> This is not precise.  Leap seconds are well defined.  You CAN calculate
> a leap second for any specific future time.

While it's possible to compute UTC - UT1 for any specific future time
you can't use this knowledge to predict when leap seconds will occur.
BIPM reserves the right to introduce leap seconds and BIPM doesn't quite
follow the leap second algorithm specified in the definition of UTC:
-- BIPM seems to have a self-imposed constraint of introducing a leap
   second on a 6 month boundary rather than a 3 month boundary
-- BIPM has been keeping UTC - UT1 smaller than the allowable 0.9 s

You can't use past BIPM behavior to predict future behavior.
BIPM will probably avoid introducing a leap second until after the 2003
IAU meeting (when the resolution to eliminate leap seconds is up for
a vote).

> It is theoretically possible that there may never be any more leap
> seconds promulgated. (not likely, I'll admit)

Actually, it's about 50% likely that no more leap seconds will be
introduced.  Not because of Earth rotation or other technical reason,
the IAU may simply vote it out of existence.

BTW: Leap seconds are improvement over the previous scheme
     (Frequent 0.1 s adjustments)
							Joe Vl