[LEAPSECS] June 30 not leap

[Zefram]

Warner Losh wrote:

>It is gratifying to see how flawlessly this standard is implemented,

>despite over 40 years of it being the standard. I guess the far older

>expectation that every minute has 60 seconds is kinda deeply engrained...


Wikipedia drily notes that "Between 1000 (when al-Biruni used seconds) and
1960 the second was defined as 1/86,400 of a mean solar day".  That 1960
endpoint to which it refers is the transition to the ephemeris second.
Rubber-seconds UTC, which has occasional minutes with !=60 seconds,
comes along in 1961.  So we've got around 960 years of the second only
being a subdivision of the minute, versus 53 years or so of seconds
being more complicated than that.

-zefram