[ntp:questions] Leap second functional question

sla29970 at gmail.com sla29970 at gmail.com
Fri Feb 22 19:43:51 UTC 2008

On Feb 22, 10:51 am, "David L. Mills" <mi... at udel.edu> wrote:
> Before 1972 there were no leap secconds; however there were periodic
> introductions of tiny rate adjustments relative to Ephemeris Time (ET)
> that drove everybody nuts.

The broadcast time signals in the 1960s were so confusing that NASA
employed a geodesist to produce an explanation of how to interpret
them.  He interviewed USNO's Markowitz, the chairman of IAU Comm 31
(Time) who was a principal in adapting cesium resonators to the scheme
of broadcast time.  The writeup is online at
The report uses terminology about time scales which was new and
evolving even at the time, and which has since been discarded, but
because it was produced for an audience other than those who ran the
time service bureaus it does define the terms pretty well -- well
enough to make it clear what a nightmare the pre-leap second scheme

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