[LEAPSECS] The Fuzzball

2017-01-09 Thread Brooks Harris
The Fuzzball https://www.eecis.udel.edu/~mills/database/papers/fuzz.pdf Ah. PDP 11 running RT11 (the RT stands for real-time, you know, and it was!). Bigger and much heavier than a breadbox it had a lot of power. Oh, wait, I mean it *used* a lot of power. And you could modify it with a

Re: [LEAPSECS] Leap seconds ain't broken, but most implementations are broken

2017-01-09 Thread Brooks Harris
As I said, Windows is huge and evolving, and Sever is different from regular Windows versions; be careful when mixing and matching versions. Some of these technotes are pretty recent, like 2014 or 2015. See - How to configure an authoritative time server in Windows Server

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Preben Nørager
On Mon Jan 9 17:38:46 EST 2017 Zefram wrote: "[Preben Nørager: So in a very long time-span the number of julian days can no longer be used without cultural bias.] What do you mean by "cultural bias" here? Are you just suggesting that TAI, by its artificiality, is an example of cultural bias,

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Preben Nørager
On Mon Jan 9 16:52:29 EST 2017 Steve Allen wrote: "As noted by the IAU recommendation two decades ago, it is important for the user to specify which time scale is being used for those days." So if I were to count days in the proleptic gregorian calendar I were to write number JD of the

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Zefram
Preben Norager wrote: >Julian days count solar days. They count whatever days they are applied to. Originally that was solar days, of course. >julian days somehow count from solar noon, and that is why I wrote the >julian period count apparent solar days. That's a misunderstanding. The Julian

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Steve Allen
On Mon 2017-01-09T22:45:19 +0100, Preben Nørager hath writ: > Julian days count solar days. No, Julian days count days. Those can be "days" in whatever time scale. The astronomical almanacs had a longstanding set of tables expressed in Julian Ephemeris Date (J.E.D.) which was a count of days of

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Preben Nørager
Dear Zefram, thank you for your comments. I have learned a lot from them, and will only discuss a few. On Mon Jan 9 13:57:13 EST 2017 you write: "No, there's no tie between Julian Dates and apparent solar time. JDs can be used equally well with apparent and mean solar time. JDs are in fact

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Preben Nørager
On Mon Jan 9 13:49:20 EST 2017 Gerry Ashton wrote: "As far as I can tell the Julian Period is no longer in use, although the derivatives, Julian date and Julian day number, are widely used in science and astronomy." The julian period is the number of julian days since the start of the julian

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Zefram
Preben Norager wrote: > if leap seconds are abolished, then the >gregorian calendar is implicitly forced on, because of the implicit >connection between the international atomic timescale, and the gregorian >calendar. There is no such connection. TAI times are

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Zefram
Preben Norager wrote: > The clock track either the sun (apparent time), or the seconds >(mean time). That's not correct. Both apparent and mean solar time are described in seconds, and in both cases that's the angular second (1/86400 circle) rather than the second of physical time.

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread John Sauter
On Mon, 2017-01-09 at 13:41 +0100, Preben Nørager wrote: > On Tue Jan 3 14:18:52 EST 2017, John Sauter wrote: > > "I regard leap seconds as a reasonable compromise between the needs > of civil time and of science. Civil time needs a clock that tracks > the days and the seasons. Science requires a

Re: [LEAPSECS] alternative to smearing

2017-01-09 Thread Preben Nørager
On Tue Jan 3 14:18:52 EST 2017, John Sauter wrote: "I regard leap seconds as a reasonable compromise between the needs of civil time and of science. Civil time needs a clock that tracks the days and the seasons. Science requires a clock that measures time in precise intervals. UTC provides both,

[LEAPSECS] IERS Bulletin C number 53

2017-01-09 Thread John Sauter
 INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS)  SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE SERVICE DE LA ROTATION TERRESTRE OBSERVATOIRE DE PARIS 61, Av. de l'Observatoire 75014 PARIS (France) Tel.  : 33 (0) 1 40 51 23 35 FAX