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#15 Julian Day Numbers
It would be nice to see HebCal updated
with julian day numbers for both Gregorian
and Herbrew Days. This would allow for
greater accuracy when it comes to days
prior to the 10 day correction by Pop Gregory.
It would also be an ideal way to correct
the assumed 0 year that does not exist
in the Gregorian calendar.
I sent an email but am posting this here
to insure that it is seen by all who are
working on this project.
Scott
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Good idea.
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Some thoughts on the differences between
the Julian and Gregorian calendars.
I've done a lot of thinking about the differnce
between the Julian calandar and the Gregorian
calandar since I posted the Julian day suggestion.
I believe that their is a misunderstanding about
the ten day correction to the calandar that occured
when Pope Gregory initiated the Gregorian calendar.
When one offsets the current Gregorian calendar by
the ten days or so that the Julian calendar is off
you end up with the Julian calendar as opposed to
the Gregorian Calendar.
The Gregorian Calendar is based on a specific year
in history that it begins as year 1 which was at
the time thought to be the birth year of Christ.
The Julian calendar however, is based on a specific
year in history that is considered the founding of
the city of Rome. Currently, the year that is observed
in both calendars are given the same numeric value
as though both Calendars are observing the same time
period when in fact they are not.
It is impossible for the Julian Calendar to be in the
year 2006 ad or ce being that it's first year of
observance was in 45 bc or bce by Julius Ceasar.
Thus the Julian calendar year ought to be at the
least 2051. When Julius Ceasar initiated the calendar
the City of Rome was considered to be 708 years old
and this was the counting of the Roman year. Therefore,
to be more accurate, the Julian Calendar year ought
to be 2759.
I do not know when the confusion between the two
calendars began but it was and is disingenuouse
to consider that both calendars are one and the
same. In this scenario, one need not consider
the ten day difference to obtain the correct
Gregorian date of an event. When one considers
the day difference between the Gregorian Calendar
and the Julian Calendar, they are actually looking
at the Julina date of the event. This difference
of dates of a given event becomes less and less
until one reaches the first century when the
difference is eliminated. Because the Julian
Calendar has more leap years than the Gregorian
Calendar, the two calendars must be considered
different Calendars not one and the same.
The mathematical equation used to determine leap
years in the Gregorian Calendar is far more accurate
than that of the Julian Calendar. While the Julian
calendar was the predecessor and the template of the
Gregorian calendar, in truth, the two calendars are
entirely different when their leap years are considered.
With this in mind, we can determine the Gregorian date
of a Hebrew event based on the alignment of the Hebrew
and Gregorian Calendars without taking into consideration
the ten day difference between the Julian Calendar and
the Gregorian Calendar. Furthermore, all bc dates ought
to be considered Gregorian calendar dates not Julian
calendar dates. This gives us an accurate Gregorian
calendar date and Hebrew calendar date alignment
for the bc years without the need to be concerned with
the ten day Julian calendar date inaccuracy as we are
focussing on the current Gregorian calendar dates and
not the previous Julian calendar dates.
The current calendar we use is the Gregorian calendar
as the previous Julian calendar was proven to be
inaccurate and flawed. Secondly, the Julian calendar
was further corrupted by the fact that the true
year of the calendar was changed at some point in
the past to reflect the current Gregorian year, thereby
eliminating it as a guide to accurate historical
time record.
Scott
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Emitting the julian day number or the (conventionally
defined) Julian calendar date is not difficult.
Scott, in implementing this feature, I do not intend to
offset the year number by 54 as you describe. Julian day
numbers are well-defined in the (astronomical) literature,
and the Julian calendar is well-understood, as far as I can
tell, to correpoond to the gregorian calendar of today, give
or take a few weeks, not tens of years.
For instance, if you were to examine a gravestone in Ireland
or Russia from the 14th century, the dates are all "off"
from our current Gregorian calation by weeks, not years.
If, on the other hand, you'd like to understand dates from
before the 8th century, that's another kettle of fish
entirely. I firmly believe that hebcal is the wrong tool
for this job, since it's very doubtful that the Jewish
calendar was computable before then.
In short, I intend to add the Julian (-10 days) calendar,
as well as astronomical Julian day numbers to hebcal, as an
option. It's possible that a tunable "cutover" date could
be implemented, but I feel that a better strategy would be a
global switch, since a "smooth" cutover likely never
happened, anywhere.
q.v. http://en.wikipedia.org/wiki/Gregorian_calendar#Timeline
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Sounds like a plan.
I found out that the switch from the Roman
AUC years to the Current BC AD year format
was implemented in 527 by the Roman abbot
Dionysius Exiguus. I always thought that
it was implemented at the same time as
the Gregorian correction. I was wrong.
Take care.
Scott
>>>>
In short, I intend to add the Julian (-10 days)
calendar, as well as astronomical Julian day
numbers to hebcal, as an option. It's possible
that a tunable "cutover" date could be implemented,
but I feel that a better strategy would be a
global switch, since a "smooth" cutover likely
never happened, anywhere.
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