+ Calendar Explanation
+We aim here to go through each Zeman and give a synopsis definition of what the Zman is about.
+Sunrise / Sunset
+Sunrise (“Netz”) is defined as the time when the uppermost edge of the solar sphere is first visible in the east. Sunset (“Shkiya”) is defined with the complete setting of the sphere in the west. Calculations are using the NOAA mathematical method.
+Seasonal Hour
+A seasonal hour is generally calculated by adding together the hours between sunrise and sunset and then dividing by twelve. The consequent result represents a singular halachic seasonal hour. It is important to mention that regarding specific halachot, like earlier Kriat Shema end time, and last time to eat hametz on Erev Pesach, the seasonal hour is calculated from daybreak until nightfall (three stars).
+For time portions calculated outside of the sunrise->sunset range for locations with a higher/lower latitude than Eretz Yisrael, there will be an astronomical discrepency for the equinox day (which is what we use to calculate all Zemanim). In the Amudeh Hora'ah calendar, we accomodate this by applying Israel's degree to the set location on the equinox day and making those minutes seasonal to apply to the general day. This means we have a matching astronomical equinox between the present land and Eretz Yisrael, as well as have a calendar that matches R' Ovadiah's Ohr Hachaim calendar in Eretz Yisrael.
+Daybreak
+Daybreak begins 72 seasonal minutes before sunrise. All mitzvot associated with beginning of day, can be fulfilled from this point in time (even though preferably one should wait until Netz under most circumstances). All fasts that start in the morning begin from daybreak as well.
+MiSheyakir
+The time of MiSheyakir is when there is just enough light that one can begin recognizing an acquaintance from close proximity. Practically, one may say Shema from now, as well as bless on טליתות ותפילין. Calculating it is preferabbly done from a seasonal hour prior to sunrise, yet one can already be lenient from 66 seasonal minutes prior to sunrise in a case of need.
+Kriat Shema End Time
+The last time to recite Kriat Shema in the morning is three seasonal hours after sunrise. However, it is proper to read the Kriat Shema at the earlier calculation of three seasonal hours after daybreak. The seasonal hours for this stringency are calculated from Daybreak to Nightfall of Rabenu Tam.
+Birkhoth Keriath Shema End Time
+One may recite the blessings of Kriat Shema only until the end of the fourth seasonal hour of the day. Also, initially one should already finish the Shacharit prayer before this time. This is also the last time to eat hametz on Erev Pesach. The only distinction though is that generally this time is calculated using the seasonal hour that is based from sunrise to sunset but in regard to hametz the seasonal hour is calculated from Daybreak to Nightfall of Rabenu Tam.
+Midday
+Midday (“Hatzot”) is precisely halfway between sunrise & sunset. It is the last time one may still pray Shacharit. The time of Hatzot also represents the halachic midnight time, which is exactly twelve fixed hours after midday. The time of halachic midnight bears ramifications regarding Selichot, Tachanun by Kriat Shema al HaMittah, and the Seder of Pesach, and other various halachot.
+Mincha Times
+The earliest one can pray mincha (“Mincha Gedolah”) is a seasonal half hour after the halachic midday. In the event the seasonal half hour is less than thirty fixed minutes the more stringent calculation of the fixed thirty minutes is imposed.
+However, it is preferable for one to wait until the 9.5th seasonal hour into the day, as this is the time for "Mincha Ketanah". We list both times, should one be in need of praying earlier.
+Plag HaMincha
+Plag Hamincha is, as the hebrew name implies (Plag=half), the halftime point from Mincha Ketanah until Shekiya. A select few mitzvot of the night can start being done from now, such as accepting Shabbat early (Orach Chayim, 273:4) or praying the night time Tefilah when one already prayed Mincha (Berachot 26a, Rabbi Yehuda).
+The definitional method to calculate this time would be to measure the time between Mincha Ketanah and sunset (which spans 2½ seasonal hours, thereby making Plag Hamincha last 1¼ seasonal hours) and apply the split time backwards from the time called "ערב". Determining when "ערב" is, though, is disputed between R' Avraham Yosef + R' Yitzhak Yosef (who say it's from צאת הכוכבים) vs R' David Yosef (who says it's from sunset). Although the position of the Halacha Berurah seems more compelling, the opinion of the Yalkut Yosef is indeed supported by many authorities as well. Therefore, one may choose to follow either opinion lemaaseh. The calendar has followed the general seasonal hours (from sunrise to sunset) for calculating Plag, even within the method of the Yalkut Yosef.
+Night (Three Stars)
+Night in halacha is defined by the emergence of three stars. Many Torah laws are predicated on the beginning of the night. Regarding most mitzvot, night begins 13½ seasonal minutes after sunset. Calculating this time in the Amudeh Hora'ah calendar is also subject to the adjusted seasonal minutes definition, as described in the "Seasonal Hour" section.
+For the Amudeh Hora'ah calendar, the stringent time for night uses an identical methodology of calculating night except it places night at twenty seasonal minutes after sunset instead of thirteen and a half. This time is meant to be used for listing the time of the end of fasts and regarding assessment whether to perform a Brit Milah on Shabbat (“Bizmano”).
+Motzeh Shabbat
+Maran HaRav Ovadya Yosef Zt”l ruled that regarding Motzeh Shabbat the listed time should be set as 30 fixed minutes after sunset. Since this ruling was for Israel, those who live in various other parts of the world must adjust the time accordingly (as mentioned in the section regarding daybreak). In order to properly conform to the physical reality consistent to thirty minutes in Israel, we have chosen to calculate the thirty minutes outside of Israel as interpreted into degrees (7.14º), which, in terms of fixed minutes after sunset, ends up varying based on both the season and location (between 34-42 minutes in New York).
+Rabenu Tam
+Maran HaRav Ovadya Yosef Zt”l held very strongly that for Motzeh Shabbat and Yom Kippur one should be stringent and abstain from melacha and most Rabbinic decrees until 72 minutes after sunset. However, many other authorities held that this isn’t essential lehalacha since historically only extremely pious individuals waited this long to take out the Shabbat. Nevertheless, the time is listed in this calendar, to afford those that wish to be strict that information. Based on the halachic rulings of the Yalkut Yosef and Halacha Berurah the 72 minutes are calculated in the lesser of two formats: 72 fixed minutes or 72 seasonal minutes.
+Molad (New Moon)
+The molad means the first sighting (“birth”) of the moon after its disappearance, which on a technical level determines the beginning of the new month. The time of the molad is the basis for determining the beginning time for “Birkat Halevana” (moon blessing). This time is not determined by an actual visual sighting of the new moon but rather is based in halachic calculations. The methodology for figuring out the calculative molad is quite complex. Many calendars list the calculated molad in terms of hours and halakim, due to the custom of some communities to announce this formula of the molad during Birkat HaChodesh. Since the normative Sephardic custom is to not make this announcement, we therefore have omitted this formulation. The formulation itself can be misleading because one assumes it to be interpreted as the actual time we use today, yet it is not the case. As an example: if the molad is written as “Sunday 6 hours and 497 parts” it would seem to mean Sunday at around 6:27 am. Yet this would be incorrect because the time actually translates to Sunday 12:06 am (Standard Israel Time). The reason is due to two factors:
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- The hours that are written are pegged to 6:00 pm (average sunset) meaning 6 hours equals 12:00 am. +
- The Standard Time which is used today around the world is a somewhat artificial time based on time zones (established a little over 100 years ago to conform to the modern eras fast pace world) and is not the true Jerusalem time. +
The latter factor is evident from the fact that the sun in Israel does not rise at the average of 6:00 am and does not set on average at 6:00 pm and is not at its exact midpoint at 12:00 pm. Midday happens in Israel when our clocks show 11:39 am and sunset is at 5:39 pm, a whole 21 minutes earlier than what our clocks say is midday and sunset respectively. It comes out that one has to add the hours and parts mentioned in calendars to the fixed hour of 5:39 pm. If we introduce daylight savings, like in the spring and summer, where we move our clocks forward one hour, then another hour is inflated into the time discrepancy, meaning Sunday 6 hours and 497 parts becomes Sunday 1:06 am).
+Another question arises is how to calculate the time of the molad for places outside of Israel. We have followed the opinion that the moment of the calculated molad is unchanging regardless of where one is located on the globe due to the fact that this position is more coherent in both fact and halacha42. Therefore, if the molad is calculated in Israel to be on Sunday 1:06 am, then at that moment exactly the molad happens everywhere else on the globe. This would mean that the time of the molad in, say, New York, is to be listed as falling on Saturday night 6:06 pm.
+Birkat HaLevana
+Although the earliest time to recite Birkat HaLevana is three complete days after the calculated molad, it is preferable (if possible, and wouldn't lead you to lose out on the Beracha) to wait seven days instead, as per our Sepharadic tradition.
+The latest time to recite Birkat HaLevana according to Maran HaRav Ovadya Yosef Zt”l is the end of the night of the fifteenth of the Jewish month. Initially, one should try to recite the bracha even before that at the calculated halfway point of the month as the Rama writes in Siman 426 (halacha 3).