Thinking about calendars.. and in particular the Hebrew...
we have the problem of "when does the day start"... the reference in the
Jewish calendar is typically the time in Jerusalem. The problem, however, is
not just Jerusalem instead of "Greenwich" but also the dynamics of the hour
to which a day begins. In UTC the day begins with the "stroke of midnight"..
a time that is always "the same": 00:00 or 23:60. A UTC day has a fixed
length of exactly 24 hours. A day in the Hebrew calendar has neither fixed
length nor fixed start or end. Within the day there are, however, two
different measures of time in use depending upon their application.
A grammar allowing for the conversion of dates and times between
the "Universal" and "Hebrew", in this light, is hardly trivial. Even worse..
Two communities in the same town can have two different accepted times for
the start and end of the day.. and in places such as Scandanavia when during
the Summer the Sun, if at all, hardly sets.. and in Winter hardly rises..
pre-set times are used.. Ilan Ramon celebrated Sabbath on the Space
Shuttle.. which was an interesting challage since a day/night cycle was a
whopping 90 min.. and to what time? To that of the place of his departure..
Cape Canaveral.. according to the customs followed by the local community
In other words.. while a calendar option might be nice.. I think its a "very
On Wed, 10 Aug 2011 17:37:39 +0200, [UTF-8?]SaaÅ¡ha Metsärantala wrote
> I would like to make a new suggestion about the calendar issue.
> > "'gregorian' is the only value defined."
> This raises the question whether:
> (implying "astronomical" numbering) is to be considered the same as
> or if negative years can not and never be assigned a calender (as of
> today's EDTF specification).
> I suggest to move the whole concept of "calendar" to EDTF phase two and in
> today's EDTF phase one, refer to ISO_8601 and only state that the
> "astronomical numbering" is default.
Edward C. Zimmermann, NONMONOTONIC LAB