[LEAPSECS] My FOSDEM slides

[Steve Allen]

On Fri 2015-03-06T21:37:42 -0700, Warner Losh hath writ:
> So it isn't outside the realm of possibilities that you'd have people making measurements
> from the late 60's till 1972 using UTC (and yes, it did exist in a practical form
> before 1972, just not in the current form and the common usage often leaves some
> ambiguity between the actual, realized form as broadcast by WWV, or the proleptic
> form w/o leap seconds). Actual measurements from this time, though, were based
> on something approaching the UTC as broadcast by WWV. Not sure how many data
> sets from that time survive until today, and how many need to be converted from that
> to UT1 or UT2, but evidentially there's some...

Yes and yes, but these are specialty applications for specialty datasets
which can only be reduced to a precise modern time scale if the original
observations and equipment were meticulously calibrated.
And then they must be reduced by going back to look at, e.g.
https://plus.google.com/photos/112320138481375234766/albums/6078225731350227361
Please don't try to make this part of a General Timestamp API.

Before 1972, for a general API, there is just UT.

--
Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
UCO/Lick Observatory--ISB   Natural Sciences II, Room 165    Lat  +36.99855
1156 High Street            Voice: +1 831 459 3046           Lng -122.06015
Santa Cruz, CA 95064        http://www.ucolick.org/~sla/     Hgt +250 m