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I once heard every 19 years it is the same. Is this true?
I once heard every 19 years it is the same. Is this true?
No, what happens every 19 years is that the lunisolar calendar restarts at approximatly the same point in the solar calendar so often dates converge every 19 years.
Isn’t 19 years the complete cycle for the Hebrew calendar leap years cycle?
Every 247 years. 13 times 19 years. Check out the Luach printed in the Tur Orach Chaim chelek bais right after Hilchos Rosh Chodesh.
I also had thought every 19 years. My Jewish and secular b-days occur together (I thought) every 19 years.
Its not excactly 19 years because of Secular Leap Days.
Also the Jewish Calender is slightly off.
The Earth Revolved around the Sun in 365 Days 5 Hours 49 Mins
The Jewish Calender assumes the Rotation is 365 Days 5 Hours 55 Mins.
Which adds about 5 Mins to every year , Over 1700 years its about a week off
Midwesterner is correct, although it should be noted that there is a small error even after 247 years and it is more accurate to say that the calendar does not really repeat itself ever.
I am not an expert by any means on this topic,but a quick check will show that ever so slowly, Pesach is moving towards the Summer and leaving Spring behind.
It is well known that Tal U’matar in Chutz La’aretz moves a day later every hundred years or so, and eventually will disappear.
There has been much controversy lately about the Luach in the back of the Tur. It is not clear that the Tur prepared it, as there is a mistake in it. The assumption is that the Tur would not have made this mistake. More likely is that at a later date, it was copied by someone else who made this mistake.
All comments about Moshiach arriving before the calendar falls apart will be well intentioned but ignore the facts and miss the point.
Oomis, the 19 year year English-Hebrew birthday thing is cute and works for the short span of our lives for most people , but not for everyone.
old man is correct, as the Levush says that the 247 year cycle is not exact, and does not repeat itself precisely. The Biur Halacha (Siman 428) lists the years were the Tur’s calendar is not exact, and the corrections.
The loss of a day every hundred years is not related at all to the calendar. The calendar is based on Tekufas Rav Ada, which is only slightly off (as mentioned by zahavasdad). For Tal U’matar we use Tekufas Shmuel, which is indeed off by 3 days every 400 years.
Old man, I know my perspective is like the blink of an eye, but in my eight years in EY, the physical signs of sprimg, wild grains and the like are always in tune with the 4 parshiot. We see the seasonality very clearly, even in a year such as this that is in the earliest part of the variation.
The first day of Spring (According to the Jewish Calender) is Tekufat Nissan , which is April 4. Pesach must be in the Spring, however in this year Peseach occurs before Tekufat Nissan
Approximately every 19 years, but it’s often off by a day in either direction due to leap years.
Unless those 19 years encompass 1582, because then it will be off by 9 days.
I also had thought every 19 years. My Jewish and secular b-days occur together (I thought) every 19 years.
For many people it works out that way.
The first time my birthdays coincide (since I was born) will be when I am 57 years old.
zahavasdad – The first day of Spring is only April 4 according to Tekufas Shmuel, which is know to be inaccurate, as is discussed at length in the Rishonim and Achronim. The calendar doesn’t use Tekufas Shmuel.
Obviously you do understand that the Tekufas Nissan is exactly when it is, as it is a physical phenomena. There cannot be a different first day of Spring according to the Jewish Calendar.
This year Pesach is March 26, and is still after the accurate Tekufah.
My Jewish birthday has been a day before my secular birthday at 19, 38, and 57. When I’m 76, they’ll coincide, but when I’m 95, there will be a two-day difference. The good news is that they’ll coincide again when I’m 114.
Does that mean that Birchas Hachama (every 27 years) is off?
Also the Jewish Calender is slightly off.
The Earth Revolved around the Sun in 365 Days 5 Hours 49 Mins
The Jewish Calender assumes the Rotation is 365 Days 5 Hours 55 Mins.
Might this have to do with the fact that days have got a fraction longer (due to earth’s rotation slowing)? Then you have negate this observation against the rate at which the earth’s orbit might be slowing down. I find anywhere that can definitely state whether the years have got fractionally longer over time. It also depends on what mean by year (tropical or sidereal).
The Jewish Calendar may have been exactly correct 1600 years ago or it might be the perfect average length of a year over the lifetime of our earth until moshiach.
Does that mean that Birchas Hachama (every 27 years) is off?
Yes
If you say birkas hachama every 27 years, you will be off until 756 years out! (27 x 28 = 756)
I once heard every 19 years it is the same. Is this true?
If you look at the time of Molad it would be even truer, but because our current calendar can be pushed off by up to almost 2 days to avoid Yom Kippur being on Friday or Sunday or Hoshana Rabba on Shabbos, hence this can push off date of Rosh haShono by up to 2 days, so not always identical every 19 years, but always within 3 day span.
Due to this ovelapping, 8 & 11 years later, tend to be very close.
This year shall be earliest since 1899, becaue Molad Tishri is less than 1&1/4 hours away from the cut offline.
By the way, Birkas haChamo is every 28 years, not 27 years. But 27 years apart tends to be very close in date, being 19+8 years.
Some Far East religions utilize an 84 year system. Again this is (4*19)+8 years apart, and is extremely accurately close.
bp27 has described the calendar and its quirks more accurately than I did. To twisted, yes, here in Eretz Yisrael Pesach is still very much in the Spring. But it is moving, ever so slowly. It will take a very long time , and you don’t have to worry.
old man – I appreciate the compliment, especially after the discussion about Rabeinu Tam on the other thread.
The solar year is 365 days. The lunar year is 354 days. Every year the solar year is 11 days longer than the lunar year. A lunar leap year, adding an extra Adar, pushes the lunar year forward by 19 days (compared to the solar year, because the leap lunar year is 374 days) for the year. By having 7 leap years in a 19-year span, we add 19 days * 7 leap years = 133. Meanwhile, we lose 11 days * 12 non-leap years = 132. The difference of 133 and 132 is usually made up by either the solar leap year of one extra day every 4 years in the form of February 29th, or by having the lunar leap year month of Adar have either one or two days Rosh Chodesh.
Fif
A solar year is NOT 365 days
Its 365 Days 5 Hours 49 Mins 1 Sec,
The extra is why we have a Leap Year (Feb 29) and why the Jullian Calender was off, Its not exactly a 1/4 of a day extra. Its a bit less
Dear bp27,
I try to be intellectually honest and to tell it the way I see it. I am old enough to have lost the fear of what people will think of my ideas. So, if a compliment is deserved,it is served. Naturally, I am limited by the rules as to what I can express.
As far as Rabeinu Tam goes, I simply cannot accept the traditional interpretation of his Bein hashmashot. I am relieved that although Rabeinu Tam’s shittah is scientifically incorrect, the new understanding of his position is intuitively attractive and makes perfect sense. His innovation that the zmanim can be independent of the position of the sun but rather be dependent on how much light there is , is wonderful and brilliant. I am sorry that large sections of pious Jews still think that it can be dark but halachically day. As I said before, no bizui chachomim is ever intended,they knew science as it existed then. And almost by definition, halachah is what we do, not what science says.
FriendInFlatbush – Unfortunately your gross oversimplification is not correct. As zahavasdad stated the Solar Leap year is to correct the roughly 1/4 day extra every year. No connection at all to the Jewish calendar, and only corrects itself, not the missing days in the 19 year cycle.
Rosh Chodesh Adar Rishon always has two days, it does not vary. The only months that vary are Cheshvan and Kislev (i.e. Rosh Chodesh Kislev and Teves).
<i>All comments about Moshiach arriving before the calendar falls apart will be well intentioned but ignore the facts and miss the point.</i>
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