This is the first in what will hopefully be a series of posts on this subject over the next year.
Guest post by Yehudah Goldreich
An Overview of Birkat HaChama
– The Blessing of the Sun –
and the 28-year Solar Cycle
On Wednesday morning, the 14th of Nisan, 5769, April 8th, Erev Pesach, we will all, with G d's help, participate in a very special event that most people only merit to do up to three times in their lives. Once every 28 years we make the bracha, blessing "Oseh Maaseh Bereshit" when the sun returns to the exact spot, on the exact day of the week, that it was placed upon the creation of the world.
In this article, I will present the sources of the bracha – Birkat HaChama, and an explanation of the astronomical, mathematical and halachic calculations of the sun's 28-year periodicity.
Click here to read moreDoes anything actually happen once every 28 years? How do we calculate when the 28-year period starts? And how does it all fit into our calendar?
Birkat HaChama Overview
The source for Birkat HaChama is the Gemara in Brachot which states:
תנו רבנן, הרואה חמה בתקופתה לבנה בגבורתה וכוכבים במסילותם ומזלות כסדרן, אומר ברוך עושה בראשית.ואימת הוי? אמר אביי כל כ"ח שנין והדר מחזור ונפלה תקופת ניסן בשבתאי באורתא דתלת נגהי ארבע.
Our rabbis taught: He who sees the sun at its season, the moon at its strength, the stars in their paths, and the constellations in their order recites "Blessed is the maker of creation".And when does this happen? Abaya says: Every 28 years when the cycle returns and the season of Nissan falls in Saturn, on the evening of Tuesday going into Wednesday.This Gemara is brought as accepted Halacha by all the halachic authorities.
"The sun at its season" is explained by Rashi as when the sun returns to the beginning of its orbit where it was at the time when the heavenly bodies were placed during creation.
The commentators understand the Gemara's question, "and when does this happen?", as well as Abaya's answer detailing the 28-year solar cycle, as referring to the first event – the sun at its season.
Once every 28 years, the Vernal Equinox (first day of spring, Rosh T’leh) falls exactly on the first hour of Wednesday evening.
How is this calculated?
The solar year, consisting of four equally long seasons (Tekufot) – Nissan, Tamuz, Tishrei and Tevet (spring, summer, autumn and winter, respectively), is defined as being exactly 365¼ days long (which is 52 full weeks, one day and 6 hours).
Since the revolutions of the sun started at creation on the first hour of the fourth day, after one full year the sun will return to its original location on Thursday midnight (one day and 6 hours after sunset on Wednesday). The next year it will return to its starting point on daybreak (6 am) Friday morning, and again the following year on Shabbat noon, etc. Only after 28 years will the sun once again return to its starting point at Wednesday nightfall.
This, although greatly simplified, is the calculation of the 28-year solar cycle where we commemorate the creation of the sun by blessing G-d – “Oseh Maaseh Bereshit” – “He who effects the work of creation”.
But now, let us delve into these calculations a bit deeper and in particular answer the following questions:
The Tekufot – The Seasons
The Gemara in Eiruvin quotes Shmuel who describes the calculations of the four seasons.
אמר שמואל אין תקופת ניסן נופלת אלא בארבעה רבעי היום או בתחלת היום או בתחלת הלילה או בחצי היום או בחצי הלילה ואין תקופת תמוז נופלת וכו'ואין בין תקופה לתקופה אלא תשעים ואחד יום ושבע שעות ומחצה
Shmuel said: The Nissan (spring) season only occurs on one of the quarters of the day – either the beginning of the day or the beginning of the night or at midday or at midnight; the Tamuz (summer) season only occurs etc.And the time between each of the seasons is exactly 91 days and 7½ hours.Shmuel defines the year as exactly 365¼ days long, divided equally into four seasons. This calculation is known as “Tekufat Shmuel” and is the basis of all halachic calculations that are dependent on the seasons. Birkat HaChama and saying “Vten Tal Umatar” outside Israel are the two halachot that are defined by the seasons. They are both calculated according to Tekufat Shmuel.
This 365¼ day calculation is also the basis of the Julian calendar, used throughout most of the world from the days of the Roman Empire until some changes were made (including skipping 10 days and redefining when leap years, February 29th, would occur) forming the Gregorian calendar in the year 1582, used in the secular world today.
Therefore, out of convenience, the date for Birkat HaChama and saying “Vten Tal Umatar” outside Israel is usually defined by the secular date.
Tekufat Nissan, according to Shmuel, will always fall on the Julian date March 26th. When the Gregorian calendar was set, this date corresponded to April 5th. In the year 1700 (because a leap year is skipped) it changed to April 6th, and again to April 7th in 1800, and presently (since 1900) Birkat HaChama is recited on April 8th.
Tekufat Rav Ada
The Rambam in Hilchot Kidush Hachodesh says that the calculation of the solar year is actually in dispute between the sages, as well as amongst the Greek and Persian astronomers.
They argue if the solar year is exactly 365 days and 6 hours (as Shmuel) or (as known as Tekufat Rav Ada) the solar year is measured as 365 days 5 hours 997 chalakim and 48 regaim (365 days 5 hours 55 minutes and 25 seconds).
The Rambam finishes his discussion of the two calculations stating that the second view (Rav Ada) is more exact and closer to the calculations of the astronomers of his time, and that these calculations were used by the Great Bet Din to calculate the calendar.
The Standard Jewish calendar
The standard Jewish calendar used today is based on the lunar month with an average time between new moons (Molad) of 29 days, 12 hours and 793 chalakim. In order to coordinate the lunar “year” with the solar year (so that Pesach will always be in the spring and Sukkot on the fall) 12 regular 12-month years together with 7 leap years consisting of 13 months are integrated into a 19-year cycle.
This 19-year cycle of 235 months (12 x 12 + 7 x 13) is coordinated exactly with 19 solar years as defined by Rav Ada.
In addition, the rule that Pesach (the 16th of Nissan) must be within the spring season (and if it “comes out” before that time, an extra month, Adar II, is added to the calendar) is only correct according to the calculations of Rav Ada. According to Shmuel’s calculations Tekufat Nissan comes out, in some years, even after Pesach!
Since our “standard” calendar is based on Rav Ada’s calculations, why is Birkat HaChama (and saying “Vten Tal Umatar”) calculated according to Shmuel?
Rav Avraham Ibn Ezra explains this seemingly contradiction that Tekufat Shmuel is based on simpler (i.e. “rounded off”) numbers in order that the calculations required for halachot that are applicable to each and every individual (Birkat HaChama and Vten Tal Umatar) be easier to calculate. But the calendar, which is only calculated by the Great Bet Din, is calculated with the more exact numbers of Rav Ada.
The Chazon Ish similarly explains that Shmuel’s easier, average calculations are used so that even those people that are not able to figure the mathematical calculations can perform the mitzvot required of them. He adds that this was as defined by Moshe at Sinai to use these calculations.
Rav Moshe Feinstein strongly reprimands someone who called Shmuel’s calculations “wrong”. Rav Moshe emphatically states that any custom followed by all the people, including our great Rabbis, over the generations can never be called “wrong”, rather there are two variant, but both acceptable, ways to calculate the seasons, and the easier (although not so accurate) method of Shmuel is the method used in certain cases.
The Rule of Shabtai - Saturn
In the Gemara in Brachot, Abaya defines Hachama Betkufata, the sun at its season:
ואימת הוי? אמר אביי כל כ"ח שנין והדר מחזור ונפלה תקופת ניסן בשבתאי באורתא דתלת נגהי ארבע.
And when does this happen? Abaya says: Every 28 years when the cycle returns and the season of Nissan falls in Shabtai (Saturn), on the evening of Tuesday going into Wednesday.What is this referring to? When is “Shabtai”, Saturn’s time? And what does this have to do with the sun?
Rashi explains that the hours of each of the days of the week are designated (or “ruled”) by one of the 7 heavenly bodies (planets) in the sky.
They are known as (in the order of their distance from the earth):
שצ"מ חנכ"ל – שבתאי, צדק, מאדים, חמה, נוגה, כוכב לבנה
Saturn, Jupiter, Mars, the Sun, Venus, Mercury and the MoonEach planet “rules” for one hour at a time finishing an even round of each of the planets by the end of a week.
We see that the first hour of Sunday (i.e. Motzaei Shabbat at sunset) is “ruled” by Kochav (Mercury), the 2nd hour by Levana (the moon), the 3rd by Shabtai (Saturn), etc.
The first hour (at nightfall) of the days of the week are defined as כצ"נ שחל"מ, and the first daytime hour of the days of the week as חל"מ כצנ"ש, as Rashi explains in detail.
In our Gemara regarding Birkat HaChama, Abaya gives the time when the sun returns to its origin point as when Tekufat Nissan (the Vernal Equinox) is on Shabtai – the first hour of Wednesday.
It must be noted that the “rule” of the planets do not have any astronomical significance. The particular planet is not in any particular place at that time. The planet “ruling” connotation is used here only as a way to name the particular hour of the day.
When did the cycle start? or, wasn’t the world created on Rosh Hashana?
Birkat HaChama is based on the premise that the sun returns to the exact spot on the day that it was created – at the beginning of the season of Nissan in the spring.
But when was the world created? Don’t we say on Rosh Hashana: “Zeh hayom techilat maasecha” – “This is the day that Your creation commenced”?
The Gemara in Rosh Hashana brings and argument regarding the matter. Rebbi Eliezer says that the world was created in Tishrei, and Rebbi Yehoshua says that the world was created in Nissan. Each one brings psukim to prove his point and explains the events in the Chumash (e.g. the dates of the flood) according to his own view. The Gemara comes to a final decision regarding the time of creation.
ת"ר חכמי ישראל מונין למבול כרבי אליעזר ולתקופה כרבי יהושע.
Our rabbis taught: The Jewish scholars count the flood as Rebbi Eliezer and the seasons as Rebbi Yehoshuah.Rashi and Tosefot both explain that the world was actually created in Nissan and therefore the calculations of the seasons are from Nissan, but even so, we calculate the events of Noah’s flood, as well as our calendar calculations from Tishrei.
Our traditional celebration of Rosh Hashana as the day that Adam was created, as well as all our (Rav Ada’s) calendar calculations, is figured following the premise that the world was created in Tishrei. But the date of Birkat HaChama, as well as any calculation of the seasons, follows the view of Rebbi Yehoshua that the world was created in Nissan.
How are the years counted? and why are we doing Birkat HaChama this year?
This year, 5769, is not divisible by 28 (there is a remainder 1), so shouldn’t we have done Birkat HaChama last year in 5768 (206 x 28 = 5768)?
It is true that the years from creation are incremented on Rosh Hashana. But both Rebbi Yehoshua (the world was created in Nissan) and Rebbi Eliezer (the world was created on the 25th of Ellul) take into account the partial year before creation (a half year per Rebbi Yehoshua or 5 days per Rebbi Eliezer) that is also counted. This “year”, known as “Shnat Tohu” - the “Year of Void”, is counted as Year 1 . Note that there is no Year 0.
Therefore, this year, “5769 years since creation” is actually the “5769th year since the counting started on the 1st of Tishrei before creation”. The sun started its cycle on the beginning of Tekufat Nissan (per Rebbi Yehoshua) in the middle of Year 1. The first Birkat HaChama, 28 years later, was in Nissan of Year 29. Therefore, we recite Birkat HaChama this year, after 206 cycles, in 5769.
 Yehudah Goldreich, a resident of Ramat Bet Shemesh, gives classes and presentations in schools on a wide variety of topics regarding the Jewish calendar.
 Mesechet Brachot, top of page 59b
 See Rambam, Hilchot Brachot, 10:18; Shulchan Aruch, Orach Chaim, 229:2; et al.
 Almost all traditional sources refer to the astronomical model described by Aristotle and the astronomer Ptolemy Claudius where all the heavenly bodies (sun, planets and stars) revolve around the earth (see Rambam, Hilchot Yesodei Hatorah, Perek 3; Rambam, Hilchot Kidush Hachodesh, Perek 11; et al) which was the accepted model of their times, rather than the present-day accepted model defined by Copernicus where the earth and planets revolve around the sun. In any case, all the measurements calculated by the traditional sources are extremely accurate in reference to any of the astronomical models.
 Note that the Talmud Yerushalmi (Perek 9, Halacha 2, Page 65B) has a different version (brought in the Aruch (“Chama”) and as quoted by Rabenu Chananel) which refers to when the sun is once again seen after not being visible for three consecutive rainy days. Although there are some poskim that suggest that it should be considered an argument regarding the requirement of the bracha, in which case a bracha is not recited, (there is even a comment brought by the Chatam Sofer (56) that in previous generations it was not accustomed to recite the bracha) but most of the accepted halachic authorities (as the Chatam Sofer himself) do require Birkat HaChama as per the Talmud Bavli.
 Tekufat Nissan, the Vernal Equinox, the first day of spring, is also known in traditional sources as “Rosh T’leh” the head of the ram or the beginning of Aries.
 Keep in mind that for all calculations in the Jewish calendar, the night precedes the day (i.e. Wednesday is defined as the 24-hour period starting from after sunset on Tuesday evening until sunset Wednesday evening.)
 Also note that all calculations in the Jewish calendar are based upon a "perfect" day consisting of 12 night hours from sunset until morning and 12 day hours from sunrise until night, throughout the entire year and for all seasons.
 Bereshit 1:14-19
 The exact spot, in relation to Eretz Israel, where the sun was placed has halachic ramifications regarding the placing of the International Date Line (see Rav. Tukechinsky’s classic sefer, HaYomam Bekadur Haaretz, and the Chazon Ish, Kuntress Yud-Chet Shaot.)
 Eiruvin 56a
 In Israel, “Vten Tal Umatar” (a prayer for rain) is added in the Shmone Esrei starting from the 7th of Marcheshvan. Outside Israel the prayer is added starting from 60 days after the beginning of Tekufat Tishrei (the autumn season) as defined by Shmuel (see Gemara Taanit 10a; Shulchan Aruch, Orach Chaim 117:1).
 Although the Gemara Taanit 10a is referring to praying for rain in Babylon, the accepted custom is to start the prayers at this date in all lands outside Israel. See the Rosh (on Taanit 10a, siman 4) who questions this, that it should be dependant on the rain requirement for each particular place and climate.
 In addition, there is another custom that is dependant on the tekufot (see Rama in Shulchan Aruch, Yoreh Deah, 116:5 and Bet Yosef, Orach Chaim, end of 455, in the name of the Mordechai) not to drink water (unless iron was placed on it) during the hour of the beginning of each of the four tekufot. See Shu”t Zemach Zedek (question 14) who discusses how the exact time of the tekufa is calculated and how it is reconciled to the day-length differences in winter and summer (unlike Birkat HaChama and Vten Tal Umatar which only the day of the tekufa, and not the hour, needs to be reckoned).
 The Julian calendar was set in the year 46 BCE.
 The Gregorian calendar was accepted only gradually throughout the years in the various European countries. Russia only converted to the Gregorian calendar in 1918 (by then they had to jump 13 days) and the Greek Orthodox church still uses the Julian calendar to calculate their holidays today.
 This is usually defined by the night (preceding) of the secular date December 5th or 6th (depending upon if the following year will be a leap year with February having 29 days.)
 The year 2000 was a leap year even in the Gregorian calendar, so the date stayed constant, but in the year 2100, the date of Birkat HaChama will once again change and will be on April 9th.
 Similarly, regarding saying “Vten Tal Umatar” the Avudraham (quoted by the Bet Yosef on the Tur, Orach Chaim 117) defines the 60 days after the tekufah as November 22 or 23, depending on the leap years (referring to the Julian calendar used in his time and place). Newer (18th century) printings of the Tur edited the dates to December 3 and 4 respectively (changing to the Gregorian calendar that was then accepted). The Kitzur Shulchan Aruch (siman 19) printed pre-1900 stated the starting dates for Vten Tal Umatar as December 4th and 5th, while today (until the year 2100) we start saying Vten Tal Umatar outside Israel the night preceding December 5th or 6th. (See Taamei Haminhagim, Inyanei Shmini Atzeret, #827, page 359-360 in the notes.)
 Rambam, Hilchot Kidush Hachodesh, Perek 9 and 10
 A “chelek” is defined as 1/1080 of an hour (or 3⅓ seconds), and a “rega” as 1/76 of a chelek (0.04386 sec.)
 Compare this to the Gregorian year of 365 days 5 hours 49 minutes and 12 seconds.
 The Rambam does note that even Rav Ada’s calculations are only approximations and not astronomically exact, and that the actual season is a few days prior to the calculated tekufot.
 Set by Hillel II the Prince in the year 4119 (369 CE).
 Rosh Hashana 21a; Sanhedrin 11b
 Birkat HaChama in the year 1953 was performed on the 23rd of Nissan. It has even occurred as late as the 26th of Nissan in 1785.
 See Shu”t Ma’asat Binyamin 101 who asks this, and also notes that our calendar is according to the view that the world was created in Tishrei and Shmuel’s calculations are according to the world being created in Nissan? This will be addressed later.
 See also Shu”t Chatam Sofer, Orach Chaim, siman 56 (also brought in Sefer Poalei Hashem, volume 3 and in the newly-published Meorot Hasofer, Inyanei Kidush HaChama Vehatekufa of the Chatam Sofer) which leaves this question unanswered as “Tzarich iyun gadol” – need a lot of thought.
 Sefer Haibur, page 8
 Actually, the Ma’asat Binyamin asks why we do not also make a bracha Birkat HaChama on the 19-year cycle as per Rav Ada? He answers that only according to Shmuel is the sun in the same position as when it was created on the same day of the week, Wednesday, while according to Rav Ada the cycle of the sun and the moon are in synchronization once every 19 years, but this never occurs on the beginning of a Wednesday as it was during creation.
 Chazon Ish, Orach Chaim, 138:4
 See Rav Chaim Kanyevsky, Sefer Shekel Hakodesh on Hilchot Kiddush Hachodesh of the Rambam, chapter 9, #20.
 Igrot Moshe, Orach Chaim, Chelek 4, Siman 17
 Mesechet Brachot, top of page 59b
 See Brachot 59b, Rashi starting Shabtai; and Eiruvin 56a, Rashi starting Ve’ein
 See Gemara Shabbat 156a which does provides significances (astrological) to the ruling planet of the hour, that the “Mazal” (“luck” or personality) of a person depends on the hour of the day that he was born (or day of the week, defined by the first hour of the day or night). The conclusion of the Gemara, though, is that “Ein mazal leyisrael” – Israel is not ruled by mazal. In addition see Shulchan Aruch, Yoreh Deah, 179:1 – not to go to astrologers.
In addition, this is the background for the custom brought by the Magen Avraham (Orach Chaim 271:1) to make Kiddush on Friday before nightfall (which is ruled by Zedek-Jupiter) and not during the first hour after nightfall (which is ruled by Maadim-Mars). See the Machazit Hashekel there, who elaborates on the issue of reckoning the hour during the winter/summer time where the days are not even (i.e. not the first hour after nightfall, rather 6 -7 pm) as is discussed by the Shu”t Zemach Zedek (see footnote 14 above). The Aruch Hashulchan (271:11) questions this custom as it if forbidden to say that we are under the influence of the mazalot.
 See Rosh Hashana 27a
 Rosh Hashana 10b
 Actually they are referring to the season of Tishrei/Nissan (and not the months) where Rebbi Eliezer calculates the world being created on the 25th of Ellul, the sun and heavenly bodies (and the beginning of the Tekufat Tishrei) on the 4th day – the 28th of Ellul, and Adam was created on Friday which was Rosh Hashana the 1st of Tishrei. Similarly, Rebbi Yehoshua calculates the world being created on the 25th of Adar, the sun (and the beginning of tekufat Nissan) on the 28th of Adar, and Adam being created on Friday the 1st of Nissan.
 Bereishit chapter 7
 Rosh Hashana 12b
 Rashi starting Chachmei and starting Uletekufa, Tosefot 12B starting Lamabul.
 Rabenu Tam (in Tosefot Rosh Hashana 27a starting Keman) also says that we hold like Rebbi Yehoshua, but ends with saying “Eilu veelu divrei elokim chaim” that both the opinions can be reconciled by saying that G-d thought of creating the world in Tishrei but actually created it in Nissan.
 There are other commentaries (Ritba, Rosh Hashana 27a; Ran, Rosh Hashana 16a) that disagree and understand that the world was created in Tishrei (also see the Ramban to Bereshit 8:5).
 Adam was created on Rosh Hashana (per Rebbi Eliezer) of the Year 2!
Wednesday, March 11, 2009
This is the first in what will hopefully be a series of posts on this subject over the next year.