On Mon 2016-04-11T10:17:33 -0400, John Sauter hath writ: > Using ancient observations of the Sun and Moon, construct a time scale > using the modern definition of Coordinated Universal Time to cover the > past 3,000 years. Use the 20th century portion of that time scale to > construct a table of leap seconds from 1900 through 1971 for NTP.
I find this to be akin to offering an answer to this question: What is the arcsine of -2? While there may be some applications which need that sort of answer, in general it is important to recognize that prior to 1972-01-01 there were no civil applications making use of SI seconds. Every practical application before 1955 was using mean solar seconds. A time scale based on SI seconds extended back to 1900 does not correspond to any contemporary use. The nature of time scales in actual use over history is necessarily piecewise continuous. Applications should be aware of that and make a choice about whether they want conceptual simplicity or a particular kind of technical accuracy. In general it is better for the characteristics of the time scale to be driven by the needs of the application rather than supplied in the absence of particular requirements. So this is cool, and may be applicable to some applications, but I'm not sure which ones those are. -- Steve Allen <[email protected]> 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 _______________________________________________ LEAPSECS mailing list [email protected] https://pairlist6.pair.net/mailman/listinfo/leapsecs
