The Last Word

[Falcon]

Re: The Last Word

 

Now you know the world is a flat disk on the back of four giant elephants that ride around on Atun' date=' the giant space turtle.[/quote']

 

I always wondered about that.

[Cancer]

Re: The Last Word

 

woah.

Are you good with calendars/maths?

 

If so I have a dousie of a problem for you.

I have been given a date in the Jewish calendar, 21st day of Nisan which I have been told corresponds to early April, 4 BC in the Gregorian calendar. I want to know which day in April. My guess is that it is in the first week.

 

Can you help me in working out an answer?

 

First, realize that your date is going to be in the Julian calendar (since Gregorian was established in 1582 IIRC, and was a discontinuity intended to bring the calendar back to the original intent of the Julian calendric reform, keeping the vernal equinox perpetually on or within a day of March 21). Fortunately, 4 BC is about 40 years after that calendar was established, and all the confusing stuff that happened at its beginning was over and done with. Next, realize that there was no "year zero", so that 4 BC means year -3 in the standard Anno Domini count. There is the minor complication that days in the Hebrew calendar begin at sunset, Jerusalem time, while our calendar conventions now have them starting at midnight. If you're after what I think you're after, you're going to have an ambiguity of date depending on whether the Birth was before or after midnight.

 

If you can keep track of those, then you should be OK.

 

That web page I linked omits the calendar conversion algorithms, so I'll have to look at my hard-copy of the book at home tonight and see what's there.

[Bazza]

Re: The Last Word

 

First, realize that your date is going to be in the Julian calendar (since Gregorian was established in 1582 IIRC, and was a discontinuity intended to bring the calendar back to the original intent of the Julian calendric reform, keeping the vernal equinox perpetually on or within a day of March 21). Fortunately, 4 BC is about 40 years after that calendar was established, and all the confusing stuff that happened at its beginning was over and done with. Next, realize that there was no "year zero", so that 4 BC means year -3 in the standard Anno Domini count. There is the minor complication that days in the Hebrew calendar begin at sunset, Jerusalem time, while our calendar conventions now have them starting at midnight. If you're after what I think you're after, you're going to have an ambiguity of date depending on whether the Birth was before or after midnight.

 

If you can keep track of those, then you should be OK.

 

That web page I linked omits the calendar conversion algorithms, so I'll have to look at my hard-copy of the book at home tonight and see what's there.

Direct quote from the book: "His birth occurred one hour after midnight on the twenty-first day of Nisan, according to the Jewish calendar, which corresponds to early April of 4 BC, according to your Gregorian calendar."

 

1) So the first thing is to take the date back to 1582 AD.

2) Is any date before then under the Julian calendar?

3) Due to the ambigutity of the quoted text it doesn't specify if I need to take the Julian calendar under consideration. Drats.

3a) with the Julian calendar does it have the standard days and months of the Gregorian calendar (that we are used too)?

3b) As I wind the calendar back, want to know if I have to adjust the days of the months besides February going back to 4BC. If all the other months have the same number of days that we are used to then it shouldn't matter (much) if I'm using the Gregorian or Juilian calendar. It should matter if calculating leap days/years is concerned though (just a guess). Am I right in this?

[AliceTheOwl]

Re: The Last Word

 

And while looking up leap years from Wikipedia' date=' it pointed to this page Famous Leap Day Babies of History In 1904 this person was born...

 

Adolph Blaine Charles David Earl Frederick Gerald Hubert Irvin John Kenneth Lloyd Martin Nero Oliver Paul Quincy Randolph Sherman Thomas Uncas Victor William Xerxes Yancy Zeus Wolfeschlegelsteinhausenberdorft Sr., Germany; had a Christian name for every letter in the alphabet, shortened it to Mr Wolfe Plus 585 Sr. The world's longest name officially used by a person.

That's quite a mouthful. I bet he changed it because his hand kept cramping up.

[Cancer]

Re: The Last Word

 

Direct quote from the book: "His birth occurred one hour after midnight on the twenty-first day of Nisan, according to the Jewish calendar, which corresponds to early April of 4 BC, according to your Gregorian calendar."

 

1) So the first thing is to take the date back to 1582 AD.

2) Is any date before then under the Julian calendar?

3) Due to the ambigutity of the quoted text it doesn't specify if I need to take the Julian calendar under consideration. Drats.

3a) with the Julian calendar does it have the standard days and months of the Gregorian calendar (that we are used too)?

3b) As I wind the calendar back, want to know if I have to adjust the days of the months besides February going back to 4BC. If all the other months have the same number of days that we are used to then it shouldn't matter (much) if I'm using the Gregorian or Juilian calendar. It should matter if calculating leap days/years is concerned though (just a guess). Am I right in this?

 

First, in answer to your questions above...

 

(1) Skip the 1582 thing. Gregorian calendar didn't exist before then. Thinking about it will just get you mixed up.

 

(2) Ideally, yes. Goofy things were done locally and intermittently. Assume you're on the standard Julian calendar unless explicitly told otherwise. In the West, there wasn't another standard, enduring calendar system besides the Julian, other than the Hebrew calendar.

 

(3) As mentioned in (2), Julian by default.

 

(3a) Yes, modulo different languages having different names for the months.

 

(3b) No, you don't have to make that adjustment. Obey the rules for the Julian calendar all the way back. The one thing that's not well defined is what to do about leap years before AD 1. In strictly mathematical principle there ought to be on in AD 0 (which doesn't exist; the year that "ought to" be AD 0 is called BC 1). The reason this is unclear is because the zero point of the Christian year counts using the Julian calendar was set long after that year count began.

 

Remember that the Julian calendar has a leap year ever 4 years, with none of the exception complexities around the "century years".

 

Second ... the number of days in a year in the Hebrew calendar varies. It varies systematically, but it varies. Seven years in nineteen there's an extra month in the year. There are some other exception rules too. So you will have probably a harder time counting back in the Hebrew calendar than with the Julian.

 

There are probably algorithms (other than counting) for converting Hebrew calendar dates to Julian calendar dates that work even that far back.

[AliceTheOwl]

Re: The Last Word

 

Man, keeping track of time was never easy, was it?

[Cancer]

Re: The Last Word

 

That's why people use Julian Day Numbers (JD) whenever possible. And then there's the further refinements of geocentric, barycentric, and heliocentric JD, when you need to get even more specific with off-Earth phenomena.

[AliceTheOwl]

Re: The Last Word

 

Julian . . . Day . . . Numbers?

 

Is that, like, 365 days in the year, 12 months in a year, 4 weeks in a month, 30 (give or take) days in a month, 7 days in a week, 24 hours in a day, etc?

[Cancer]

Re: The Last Word

 

Julian Day numbers (JD) are a simple running count of days from a specific point in the remote past (Jan 1 4713 BC, proleptic Julian calendar). The "remote past" thing was done so no historical event would have a negative JD. Time intervals between events become as simple as subtracting one JD from the other. The hard part becomes translating each civil calendar date into JD.

 

Bazza, I found an algorithm for converting Julian Calendar date to JD, but not one for converting Hebrew calendar date to JD. OTOH, there is a converter here, but I haven't looked at it to see what it does and how it works.

[Bazza]

Re: The Last Word

 

Bazza' date=' I found an algorithm for converting Julian Calendar date to JD, but not one for converting Hebrew calendar date to JD. OTOH, there is a converter here, but I haven't looked at it to see what it does and how it works.

That helped immensely, once I got used to the interface.

 

It did bring up this conundrum though:

 

Gregorian: April 4, 3 B.C.

Julian: April 6, 3 B.C.

Jewish: Nisan 21, 3758

Weekday: Saturday

 

I realised I made a mistake, I used -3 thinking it was 4 BC. Darn, so very close. The corrected results is:

 

Gregorian: April 16, 4 B.C. (ante ¹)

Julian: April 18, 4 B.C.

Jewish: Nisan 21, 3757

Weekday: Wednesday

 

So which day do I use, the Julian for the Gregorian? Edit: I found out by looking at the calendar in qustion and it showed me in a pop-up, it is the 16th (Gregorian).

 

Also, the 16 or the 18 isn't "early April" (Italics mine) as per the quote from the book. *enigmatically puzzled*

[L. Marcus]

Re: The Last Word

 

Immensely

[Bazza]

Re: The Last Word

 

Immensely

That was immensely helpful. Darn "a"s and "e"s.

[Bazza]

Re: The Last Word

 

Never ask time-related rhetorical questions to astronomers. Eg:

 

Man' date=' keeping track of time was never easy, was it?[/quote']

 

That's why people use Julian Day Numbers (JD) whenever possible. And then there's the further refinements of geocentric' date=' barycentric, and heliocentric JD, when you need to get even more specific with off-Earth phenomena.[/quote']

 

[L. Marcus]

Re: The Last Word

 

Astros can be darn handy at times, though.

[Bazza]

Re: The Last Word

 

Astros can be darn handy at times' date=' though.[/quote'] *groan* for the pun.

 

I was going to make a worse one though... As cosmos is a synonym of "astro-" I was going to say something like this: sex-staved astronauts read Cosmo.

 

See, I told you, a much worse pun.

[L. Marcus]

Re: The Last Word

 

*groan*, for sure!

 

[Bazza]

Re: The Last Word

 

yep.

 

night night!!!

[Cancer]

Re: The Last Word

 

That helped immensely, once I got used to the interface.

 

It did bring up this conundrum though:

 

Gregorian: April 4, 3 B.C.

Julian: April 6, 3 B.C.

Jewish: Nisan 21, 3758

Weekday: Saturday

 

I realised I made a mistake, I used -3 thinking it was 4 BC. Darn, so very close. The corrected results is:

 

Gregorian: April 16, 4 B.C. (ante ¹)

Julian: April 18, 4 B.C.

Jewish: Nisan 21, 3757

Weekday: Wednesday

 

So which day do I use, the Julian for the Gregorian? Edit: I found out by looking at the calendar in qustion and it showed me in a pop-up, it is the 16th (Gregorian).

 

Also, the 16 or the 18 isn't "early April" (Italics mine) as per the quote from the book. *enigmatically puzzled*

 

??

 

You're specifically investigating 4 BC, right? That is -3 as you should enter it into a program. See what happens when you count backwards:

(...)

AD 2

AD 1

"AD 0" = BC 1 because AD 0 doesn't exist

... -1 = BC 2

... -2 = BC 3

... -3 = BC 4

 

So the number you plug in for Julian (or Gregorian) calendar year is -3 when you want 4 BC.

 

I am pretty sure you want Julian calendar. I admit I'm puzzled why there's a two-day difference between the two as it falls out. Ideally, the Gregorian and Julian calendars ought to be in sync at some point in time, presumably the point at which the Julian calendar was first used (which was only about 45 BC, so there's no century-year leap day exception between the date of interest and the beginning of the calendar), and they drift apart with the century-year exceptions in the Gregorian system. Now, because of the oddball situation where AD 0 doesn't exist (so it's not well defined what happens with a leap year that "should" happen then), I can see a one-day difference at AD -3. But a 2-day difference puzzles me.

[AliceTheOwl]

Re: The Last Word

 

*groan* for the pun.

 

I was going to make a worse one though... As cosmos is a synonym of "astro-" I was going to say something like this: sex-staved astronauts read Cosmo.

 

See, I told you, a much worse pun.

If you'd ever read Cosmo, you'd know just how bad.

[Cancer]

Re: The Last Word

 

Cosmo and the Necronomicon are similar ... they cause SAN loss when you read them.

[AliceTheOwl]

Re: The Last Word

 

More if you're the target audience, I suspect.

[Bazza]

Re: The Last Word

 

??

 

You're specifically investigating 4 BC, right? That is -3 as you should enter it into a program. See what happens when you count backwards:

(...)

AD 2

AD 1

"AD 0" = BC 1 because AD 0 doesn't exist

... -1 = BC 2

... -2 = BC 3

... -3 = BC 4

 

So the number you plug in for Julian (or Gregorian) calendar year is -3 when you want 4 BC.

I did that, "0" and "-1" both give the year as 1 BC. For each year BC you need to enter a minus in front. But that doesn't answer the question of the 16th of April.

 

I am pretty sure you want Julian calendar. I admit I'm puzzled why there's a two-day difference between the two as it falls out. Ideally, the Gregorian and Julian calendars ought to be in sync at some point in time, presumably the point at which the Julian calendar was first used (which was only about 45 BC, so there's no century-year leap day exception between the date of interest and the beginning of the calendar), and they drift apart with the century-year exceptions in the Gregorian system. Now, because of the oddball situation where AD 0 doesn't exist (so it's not well defined what happens with a leap year that "should" happen then), I can see a one-day difference at AD -3. But a 2-day difference puzzles me.

Me too. I wondered before about the leap year at year "zero"/1 BC and as you said that would account for a one day difference. But the two day difference is...puzzeling.

 

One potential solution is to go back to when the Julian/Gregoriian calendar were created and presumably aligned, find the JD number and then advance it to 1 BC and then it should be easier to find out the extra leap day, as this day would have it's unique JD number.

[Bazza]

Re: The Last Word

 

Cosmo and the Necronomicon are similar ... they cause SAN loss when you read them.

I read them both for the pictures

 

Oooo, the Azathoth centerfold is hawt.

[AliceTheOwl]

Re: The Last Word

 

I read them both for the pictures

 

Oooo, the Azathoth centerfold is hawt.

If you swing that way . . .

[Cancer]

Re: The Last Word

 

I read them both for the pictures

 

Oooo, the Azathoth centerfold is hawt.

 

In the same sense as a book printed on plutonium foil, I suppose.