Posted on 03/03/2005 6:10:29 PM PST by A. Pole
It is now: 2453433.72656
Julian dates (abbreviated JD) are simply a continuous count of days and fractions since noon Universal Time on January 1, 4713 BCE (on the Julian calendar). Almost 2.5 million days have transpired since this date. Julian dates are widely used as time variables within astronomical software. Typically, a 64-bit floating point (double precision) variable can represent an epoch expressed as a Julian date to about 1 millisecond precision. Note that the time scale that is the basis for Julian dates is Universal Time, and that 0h UT corresponds to a Julian date fraction of 0.5.
It is assumed that 7-day weeks have formed an uninterrupted sequence since ancient times. Thus, the day of the week can be obtained from the remainder of the division of the Julian date by 7.
Calendar dates — year, month, and day — are more problematic. Various calendar systems have been in use at different times and places around the world. This application deals with only two: the Gregorian calendar, now used universally for civil purposes, and the Julian calendar, its predecessor in the western world. As used here, the two calendars have identical month names and number of days in each month, and differ only in the rule for leap years. The Julian calendar has a leap year every fourth year, while the Gregorian calendar has a leap year every fourth year except century years not exactly divisible by 400.
This application assumes that the changeover from the Julian calendar to the Gregorian calendar occurred in October of 1582, according to the scheme instituted by Pope Gregory XIII. Specifically, for dates on or before 4 October 1582, the Julian calendar is used; for dates on or after 15 October 1582, the Gregorian calendar is used. Thus, there is a ten-day gap in calendar dates, but no discontinuity in Julian dates or days of the week: 4 October 1582 (Julian) is a Thursday, which begins at JD 2299159.5; and 15 October 1582 (Gregorian) is a Friday, which begins at JD 2299160.5. The omission of ten days of calendar dates was necessitated by the astronomical error built up by the Julian calendar over its many centuries of use, due to its too-frequent leap years.
The changeover to the Gregorian calendar system occurred as described above only in Roman Catholic countries, however. Adoption of the Gregorian calendar in the rest of the world progressed slowly. For example, for England and its colonies, the change did not occur until September 1752. (The Unix cal command for systems manufactured in the U.S. reflects the 1752 changeover.)
For a list of when certain countries switched to the Gregorian calendar, see section 2.2.4 of Claus Tøndering's Calendar FAQ. More information on calendars and their histories can be found in L. E. Doggett's "Calendars" chapter of the Explanatory Supplement to the Astronomical Almanac (ed. P.K. Seidelmann, 1992, University Science Books).
So, like, what's the date in the metric system?
Hint: This is the biblical date of creation!
Now, can you explain to us why Christians would be offended by the Julian date?
JD is metric!
Wow! I'm gettin smart! What about those dates from the French Revolution, where they only had about 10 months? The only one I remember is "Thermidor".
However, for the purpose of this topic, the concept of Julian dates was appropriate. Notice the reference to January 1, 4713 BCE as the official starting time.
BCE
This recognizes both the biblical date of creation, and also our common dating system which is based upon the life of Jesus.
Can you explain to us, why this would offend any Christian?
This is pretty common here in the USA as well.
Most of my textbooks use the terms BCE and CE.
I don't like it, but I get worked up about other stuff more.
Teachers below college still usually call it BC and AD though.
I love the poem Ozymandius......though that is not your name.
Anyway, I am not really that offended either. I am not excited about it, but I will just say Before the Christian Era and the Christian Era.
As with the Julian dating system (which I use every day), the need for a common terminology, which every civilization could use, was apparent.
If each individual country, locality, religion, denomination, or all of the fragmented segments of human society used their uniqe form of dating, it would soon become absolute chaos!
The Julian date is the official scientific system, and the "Current Era" (CE) terminology has been accepted by all countries around the world.
This was adopted as a compromise, which best respected all cultures and religions.
Hint: The usage of BCE and CE, were selected with that in mind...
Because to say Before the Christian era allows you to acknowledge Christianity and deny Christ.
Total nonsense. If one doesn't subscribe to the religious connotations, then the "historical" connotations are moot at best, and laughably absurd at worst, and need not be considered. This "Common Era/Before Common Era" nonsense is nothing more than "changing the times and the seasons", as it were, to shut out Christ entirely, and no believer should participate...
the infowarrior
That was very well stated, on JD 2453433.84464
"The only people who get offended or upset by such things are people who go looking for things to offend them. To hell with such people!"
I guess that means you won't sign my petition to rename the days of the week so we don't refer to Roman and Norse gods?
the infowarrior
Not really -- the Hindus etc. have no objection to using the term BC and AD --> the ones pushing for these changes are libs and athiests
He said "BCE" and "CE" were a step in the right direction because, after all, they don't follow Christ.
Whether he spoke for ALL Hindus or just the ones he represented is, of course, open to question.
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