Class ComplexZmanimCalendar

All Implemented Interfaces:
Cloneable

This class extends ZmanimCalendar and provides many more zmanim than available in the ZmanimCalendar. The basis for most zmanim in this class are from the sefer Yisroel Vehazmanim by Rabbi Yisrael Dovid Harfenes. As an example of the number of different zmanim made available by this class, there are methods to return 18 different calculations for alos (dawn), 18 for plag hamincha and 29 for tzais available in this API. The real power of this API is the ease in calculating zmanim that are not part of the library. The methods for zmanim calculations not present in this class or it's superclass ZmanimCalendar are contained in the AstronomicalCalendar, the base class of the calendars in our API since they are generic methods for calculating time based on degrees or time before or after sunrise and sunset and are of interest for calculation beyond zmanim calculations. Here are some examples.

First create the Calendar for the location you would like to calculate:

 String locationName = "Lakewood, NJ";
 double latitude = 40.0828; // Lakewood, NJ
 double longitude = -74.222; // Lakewood, NJ
 double elevation = 20; // optional elevation correction in Meters
 // the String parameter in getTimeZone() has to be a valid timezone listed in
 // TimeZone.getAvailableIDs()
 TimeZone timeZone = TimeZone.getTimeZone("America/New_York");
 GeoLocation location = new GeoLocation(locationName, latitude, longitude, elevation, timeZone);
 ComplexZmanimCalendar czc = new ComplexZmanimCalendar(location);
 // Optionally set the date or it will default to today's date
 czc.getCalendar().set(Calendar.MONTH, Calendar.FEBRUARY);
 czc.getCalendar().set(Calendar.DAY_OF_MONTH, 8);

Note: For locations such as Israel where the beginning and end of daylight savings time can fluctuate from year to year, if your version of Java does not have an up to date timezone database, create a SimpleTimeZone with the known start and end of DST. To get alos calculated as 14° below the horizon (as calculated in the calendars published in Montreal), add AstronomicalCalendar.GEOMETRIC_ZENITH (90) to the 14° offset to get the desired time:

  Date alos14 = czc.getSunriseOffsetByDegrees(AstronomicalCalendar.GEOMETRIC_ZENITH + 14);

To get mincha gedola calculated based on the Magen Avraham (MGA) using a shaah zmanis based on the day starting 16.1° below the horizon (and ending 16.1° after sunset) the following calculation can be used:

 Date minchaGedola = czc.getTimeOffset(czc.getAlos16point1Degrees(), czc.getShaahZmanis16Point1Degrees() * 6.5);

or even simpler using the included convenience methods

 Date minchaGedola = czc.getMinchaGedola(czc.getAlos16point1Degrees(), czc.getShaahZmanis16Point1Degrees());

A little more complex example would be calculating zmanim that rely on a shaah zmanis that is not present in this library. While a drop more complex, it is still rather easy. An example would be to calculate the Trumas Hadeshen's alos to tzais based plag hamincha as calculated in the Machzikei Hadass calendar in Manchester, England. A number of this calendar's zmanim are calculated based on a day starting at alos of 12° before sunrise and ending at tzais of 7.083° after sunset. Be aware that since the alos and tzais do not use identical degree-based offsets, this leads to chatzos being at a time other than the solar transit (solar midday). To calculate this zman, use the following steps. Note that plag hamincha is 10.75 hours after the start of the day, and the following steps are all that it takes.

 Date plag = czc.getPlagHamincha(czc.getSunriseOffsetByDegrees(AstronomicalCalendar.GEOMETRIC_ZENITH + 12),
                                czc.getSunsetOffsetByDegrees(AstronomicalCalendar.GEOMETRIC_ZENITH + ZENITH_7_POINT_083));

Something a drop more challenging, but still simple, would be calculating a zman using the same "complex" offset day used in the above-mentioned Manchester calendar, but for a shaos zmaniyos based zman not supported by this library, such as calculating the point that one should be makpid not to eat on erev Shabbos or erev Yom Tov. This is 9 shaos zmaniyos into the day.

  1. Calculate the shaah zmanis in milliseconds for this day
  2. Add 9 of these shaos zmaniyos to alos starting at 12°

 long shaahZmanis = czc.getTemporalHour(czc.getSunriseOffsetByDegrees(AstronomicalCalendar.GEOMETRIC_ZENITH + 12),
                                                czc.getSunsetOffsetByDegrees(AstronomicalCalendar.GEOMETRIC_ZENITH + ZENITH_7_POINT_083));
 Date sofZmanAchila = getTimeOffset(czc.getSunriseOffsetByDegrees(AstronomicalCalendar.GEOMETRIC_ZENITH + 12),
                                        shaahZmanis * 9);

Calculating this sof zman achila according to the GRA is simplicity itself.

 Date sofZmanAchila = czc.getTimeOffset(czc.getSunrise(), czc.getShaahZmanisGra() * 9);

Documentation from the ZmanimCalendar parent class

The ZmanimCalendar is a specialized calendar that can calculate sunrise, sunset and Jewish zmanim (religious times) for prayers and other Jewish religious duties. This class contains the main functionality of the Zmanim library. For a much more extensive list of zmanim, use the ComplexZmanimCalendar that extends this class. See documentation for the ComplexZmanimCalendar and AstronomicalCalendar for simple examples on using the API. Elevation based zmanim (even sunrise and sunset) should not be used lekula without the guidance of a posek. According to Rabbi Dovid Yehudah Bursztyn in his Zmanim Kehilchasam, 7th edition chapter 2, section 7 (pages 181-182) and section 9 (pages 186-187), no zmanim besides sunrise and sunset should use elevation. However, Rabbi Yechiel Avrahom Zilber in the Birur Halacha Vol. 6 Ch. 58 Pages 34 and 42 is of the opinion that elevation should be accounted for in zmanim calculations. Related to this, Rabbi Yaakov Karp in Shimush Zekeinim, Ch. 1, page 17 states that obstructing horizons should be factored into zmanim calculations. The setting defaults to false (elevation will not be used for zmanim calculations besides sunrise and sunset), unless the setting is changed to true in ZmanimCalendar.setUseElevation(boolean). This will impact sunrise and sunset-based zmanim such as AstronomicalCalendar.getSunrise(), AstronomicalCalendar.getSunset(), ZmanimCalendar.getSofZmanShmaGRA(), alos-based zmanim such as ZmanimCalendar.getSofZmanShmaMGA() that are based on a fixed offset of sunrise or sunset and zmanim based on a percentage of the day such as getSofZmanShmaMGA90MinutesZmanis() that are based on sunrise and sunset. Even when set to true it will not impact zmanim that are a degree-based offset of sunrise and sunset, such as getSofZmanShmaMGA16Point1Degrees() or getSofZmanShmaBaalHatanya() since these zmanim are not linked to sunrise or sunset times (the calculations are based on the astronomical definition of sunrise and sunset calculated in a vacuum with the solar radius above the horizon), and are therefore not impacted by the use of elevation. For additional information on the halachic impact of elevation on zmanim see:

Note: It is important to read the technical notes on top of the AstronomicalCalculator documentation before using this code.

I would like to thank Rabbi Yaakov Shakow, the author of Luach Ikvei Hayom who spent a considerable amount of time reviewing, correcting and making suggestions on the documentation in this library.

Disclaimer:

I did my best to get accurate results, but please double-check before relying on these zmanim for halacha lema'aseh.
Author:
© Eliyahu Hershfeld 2004 - 2024
  • Field Details

  • Constructor Details

  • Method Details

    • getShaahZmanis19Point8Degrees

      Method to return a shaah zmanis (temporal hour) calculated using a 19.8° dip. This calculation divides the day based on the opinion of the Magen Avraham (MGA) that the day runs from dawn to dusk. Dawn for this calculation is when the sun is 19.8° below the eastern geometric horizon before sunrise. Dusk for this is when the sun is 19.8° below the western geometric horizon after sunset. This day is split into 12 equal parts with each part being a shaah zmanis.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getShaahZmanis18Degrees

      public long getShaahZmanis18Degrees()
      Method to return a shaah zmanis (temporal hour) calculated using a 18° dip. This calculation divides the day based on the opinion of the Magen Avraham (MGA) that the day runs from dawn to dusk. Dawn for this calculation is when the sun is 18° below the eastern geometric horizon before sunrise. Dusk for this is when the sun is 18° below the western geometric horizon after sunset. This day is split into 12 equal parts with each part being a shaah zmanis.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getShaahZmanis26Degrees

      public long getShaahZmanis26Degrees()
      Method to return a shaah zmanis (temporal hour) calculated using a dip of 26°. This calculation divides the day based on the opinion of the Magen Avraham (MGA) that the day runs from dawn to dusk. Dawn for this calculation is when the sun is 26° below the eastern geometric horizon before sunrise. Dusk for this is when the sun is 26° below the western geometric horizon after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. Since zmanim that use this method are extremely late or early and at a point when the sky is a long time past the 18° point where the darkest point is reached, zmanim that use this should only be used lechumra, such as delaying the start of nighttime mitzvos.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanis16Point1Degrees

      Method to return a shaah zmanis (temporal hour) calculated using a dip of 16.1°. This calculation divides the day based on the opinion that the day runs from dawn to dusk. Dawn for this calculation is when the sun is 16.1° below the eastern geometric horizon before sunrise and dusk is when the sun is 16.1° below the western geometric horizon after sunset. This day is split into 12 equal parts with each part being a shaah zmanis.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanis60Minutes

      public long getShaahZmanis60Minutes()
      Method to return a shaah zmanis (solar hour) according to the opinion of the Magen Avraham (MGA). This calculation divides the day based on the opinion of the MGA that the day runs from dawn to dusk. Dawn for this calculation is 60 minutes before sunrise and dusk is 60 minutes after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. Alternate methods of calculating a shaah zmanis are available in the subclass ComplexZmanimCalendar.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanis72Minutes

      public long getShaahZmanis72Minutes()
      Method to return a shaah zmanis (solar hour) according to the opinion of the Magen Avraham (MGA). This calculation divides the day based on the opinion of the MGA that the day runs from dawn to dusk. Dawn for this calculation is 72 minutes before sunrise and dusk is 72 minutes after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. Alternate methods of calculating a shaah zmanis are available in the subclass ComplexZmanimCalendar.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getShaahZmanis72MinutesZmanis

      Method to return a shaah zmanis (temporal hour) according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes zmaniyos before sunrise. This calculation divides the day based on the opinion of the MGA that the day runs from dawn to dusk. Dawn for this calculation is 72 minutes zmaniyos before sunrise and dusk is 72 minutes zmaniyos after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. This is identical to 1/10th of the day from sunrise to sunset.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanis90Minutes

      public long getShaahZmanis90Minutes()
      Method to return a shaah zmanis (temporal hour) calculated using a dip of 90 minutes. This calculation divides the day based on the opinion of the Magen Avraham (MGA) that the day runs from dawn to dusk. Dawn for this calculation is 90 minutes before sunrise and dusk is 90 minutes after sunset. This day is split into 12 equal parts with each part being a shaah zmanis.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getShaahZmanis90MinutesZmanis

      Method to return a shaah zmanis (temporal hour) according to the opinion of the Magen Avraham (MGA) based on alos being 90 minutes zmaniyos before sunrise. This calculation divides the day based on the opinion of the MGA that the day runs from dawn to dusk. Dawn for this calculation is 90 minutes zmaniyos before sunrise and dusk is 90 minutes zmaniyos after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. This is 1/8th of the day from sunrise to sunset.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanis96MinutesZmanis

      Method to return a shaah zmanis (temporal hour) according to the opinion of the Magen Avraham (MGA) based on alos being 96 minutes zmaniyos before sunrise. This calculation divides the day based on the opinion of the MGA that the day runs from dawn to dusk. Dawn for this calculation is 96 minutes zmaniyos before sunrise and dusk is 96 minutes zmaniyos after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. This is identical to 1/7.5th of the day from sunrise to sunset.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanisAteretTorah

      Method to return a shaah zmanis (temporal hour) according to the opinion of the Chacham Yosef Harari-Raful of Yeshivat Ateret Torah calculated with alos being 1/10th of sunrise to sunset day, or 72 minutes zmaniyos of such a day before sunrise, and tzais is usually calculated as 40 minutes (configurable to any offset via setAteretTorahSunsetOffset(double)) after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. Note that with this system, chatzos (midday) will not be the point that the sun is halfway across the sky.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanisAlos16Point1ToTzais3Point8

      Method to return a shaah zmanis (temporal hour) used by some zmanim according to the opinion of Rabbi Yaakov Moshe Hillel as published in the luach of the Bais Horaah of Yeshivat Chevrat Ahavat Shalom that is based on a day starting 72 minutes before sunrise in degrees alos 16.1° and ending 14 minutes after sunset in degrees tzais 3.8°. This day is split into 12 equal parts with each part being a shaah zmanis. Note that with this system, chatzos (midday) will not be the point that the sun is halfway across the sky. These shaos zmaniyos are used for Mincha Ketana and Plag Hamincha. The 14 minutes are based on 3/4 of an 18 minute mil, with half a minute added for Rav Yosi.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanisAlos16Point1ToTzais3Point7

      Method to return a shaah zmanis (temporal hour) used by some zmanim according to the opinion of Rabbi Yaakov Moshe Hillel as published in the luach of the Bais Horaah of Yeshivat Chevrat Ahavat Shalom that is based on a day starting 72 minutes before sunrise in degrees alos 16.1° and ending 13.5 minutes after sunset in degrees tzais 3.7°. This day is split into 12 equal parts with each part being a shaah zmanis. Note that with this system, chatzos (midday) will not be the point that the sun is halfway across the sky. These shaos zmaniyos are used for Mincha Gedola calculation.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanis96Minutes

      public long getShaahZmanis96Minutes()
      Method to return a shaah zmanis (temporal hour) calculated using a dip of 96 minutes. This calculation divides the day based on the opinion of the Magen Avraham (MGA) that the day runs from dawn to dusk. Dawn for this calculation is 96 minutes before sunrise and dusk is 96 minutes after sunset. This day is split into 12 equal parts with each part being a shaah zmanis.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getShaahZmanis120Minutes

      public long getShaahZmanis120Minutes()
      Method to return a shaah zmanis (temporal hour) calculated using a dip of 120 minutes. This calculation divides the day based on the opinion of the Magen Avraham (MGA) that the day runs from dawn to dusk. Dawn for this calculation is 120 minutes before sunrise and dusk is 120 minutes after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. Since zmanim that use this method are extremely late or early and at a point when the sky is a long time past the 18° point where the darkest point is reached, zmanim that use this should only be used lechumra only, such as delaying the start of nighttime mitzvos.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanis120MinutesZmanis

      Method to return a shaah zmanis (temporal hour) according to the opinion of the Magen Avraham (MGA) based on alos being 120 minutes zmaniyos before sunrise. This calculation divides the day based on the opinion of the MGA that the day runs from dawn to dusk. Dawn for this calculation is 120 minutes zmaniyos before sunrise and dusk is 120 minutes zmaniyos after sunset. This day is split into 12 equal parts with each part being a shaah zmanis. This is identical to 1/6th of the day from sunrise to sunset. Since zmanim that use this method are extremely late or early and at a point when the sky is a long time past the 18° point where the darkest point is reached, zmanim that use this should only be used lechumra such as delaying the start of nighttime mitzvos.
      Returns:
      the long millisecond length of a shaah zmanis. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha120MinutesZmanis

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha based on sunrise being 120 minutes zmaniyos or 1/6th of the day before sunrise. This is calculated as 10.75 hours after dawn. The formula used is 10.75 * getShaahZmanis120MinutesZmanis() after dawn. Since the zman based on an extremely early alos and a very late tzais, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha120Minutes

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha according to the Magen Avraham with the day starting 120 minutes before sunrise and ending 120 minutes after sunset. This is calculated as 10.75 hours after dawn 120 minutes. The formula used is 10.75 getShaahZmanis120Minutes() after getAlos120(). Since the zman based on an extremely early alos and a very late tzais, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos60

      public Date getAlos60()
      * Method to return alos (dawn) calculated as 60 minutes before sunrise or sea level sunrise (depending on the ZmanimCalendar.isUseElevation() setting). This is the time to walk the distance of 4 mil at 15 minutes a mil. This seems to be the opinion of the Chavas Yair in the Mekor Chaim, Orach Chaim Ch. 90, though the Mekor Chaim in Ch. 58 and in the Chut Hashani Ch. 97 states that a person walks 3 and a 1/3 mil in an hour, or an 18-minute mil. Also see the Divrei Malkiel Vol. 4, Ch. 20, page 34) who mentions the 15 minute mil lechumra by baking matzos. Also see the Maharik Ch. 173 where the questioner quoting the Ra'avan is of the opinion that the time to walk a mil is 15 minutes (5 mil in a little over an hour). There are many who believe that there is a ta'us sofer (scribe's error) in the Ra'avan, and it should 4 mil in a little over an hour, or an 18-minute mil. Time based offset calculations are based on the opinion of the Rishonim who stated that the time of the neshef (time between dawn and sunrise) does not vary by the time of year or location but purely depends on the time it takes to walk the distance of 4* mil. getTzaisGeonim9Point75Degrees() is a related zman that is a degree-based calculation based on 60 minutes.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar. documentation.
      See Also:
    • getAlos72Zmanis

      Method to return alos (dawn) calculated using 72 minutes zmaniyos or 1/10th of the day before sunrise. This is based on an 18-minute mil so the time for 4 mil is 72 minutes which is 1/10th of a day (12 * 60 = 720) based on the day being from sea level sunrise to sea level sunset or sunrise to sunset (depending on the ZmanimCalendar.isUseElevation() setting). The actual calculation is AstronomicalCalendar.getSeaLevelSunrise() - (ZmanimCalendar.getShaahZmanisGra() * 1.2). This calculation is used in the calendars published by the Hisachdus Harabanim D'Artzos Habris Ve'Canada.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos96

      public Date getAlos96()
      Method to return alos (dawn) calculated using 96 minutes before sunrise or sea level sunrise (depending on the ZmanimCalendar.isUseElevation() setting) that is based on the time to walk the distance of 4 mil at 24 minutes a mil. Time based offset calculations for alos are based on the opinion of the Rishonim who stated that the time of the Neshef (time between dawn and sunrise) does not vary by the time of year or location but purely depends on the time it takes to walk the distance of 4 mil.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getAlos90Zmanis

      Method to return alos (dawn) calculated using 90 minutes zmaniyos or 1/8th of the day before sunrise or sea level sunrise (depending on the ZmanimCalendar.isUseElevation() setting). This is based on a 22.5-minute mil so the time for 4 mil is 90 minutes which is 1/8th of a day (12 * 60) / 8 = 90. The day is calculated from sea level sunrise to sea level sunset or sunrise to sunset (depending on the ZmanimCalendar.isUseElevation(). The actual calculation used is AstronomicalCalendar.getSunrise() - (ZmanimCalendar.getShaahZmanisGra() * 1.5).
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos96Zmanis

      This method returns alos (dawn) calculated using 96 minutes zmaniyos or 1/7.5th of the day before sunrise or sea level sunrise (depending on the ZmanimCalendar.isUseElevation() setting). This is based on a 24-minute mil so the time for 4 mil is 96 minutes which is 1/7.5th of a day (12 * 60 / 7.5 = 96). The day is calculated from sea level sunrise to sea level sunset or sunrise to sunset (depending on the ZmanimCalendar.isUseElevation(). The actual calculation used is AstronomicalCalendar.getSunrise() - (ZmanimCalendar.getShaahZmanisGra() * 1.6).
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos90

      public Date getAlos90()
      Method to return alos (dawn) calculated using 90 minutes before sea level sunrise based on the time to walk the distance of 4 mil at 22.5 minutes a mil. Time-based offset calculations for alos are based on the opinion of the Rishonim who stated that the time of the Neshef (time between dawn and sunrise) does not vary by the time of year or location but purely depends on the time it takes to walk the distance of 4 mil.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getAlos120

      Deprecated.
      This method should be used lechumra only (such as stopping to eat at this time on a fast day), since it returns a very early time, and if used lekula can result in doing mitzvos hayom too early according to most opinions. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns alos (dawn) calculated using 120 minutes before sea level sunrise (no adjustment for elevation is made) based on the time to walk the distance of 5 mil (Ula) at 24 minutes a mil. Time based offset calculations for alos are based on the* opinion of the Rishonim who stated that the time of the neshef (time between dawn and sunrise) does not vary by the time of year or location but purely depends on the time it takes to walk the distance of 5 mil (Ula). Since this time is extremely early, it should only be used lechumra, such as not eating after this time on a fast day, and not as the start time for mitzvos that can only be performed during the day.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos120Zmanis

      Deprecated.
      This method should be used lechumra only (such as stopping to eat at this time on a fast day), since it returns a very early time, and if used lekula can result in doing mitzvos hayom too early according to most opinions. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and method returns alos (dawn) calculated using 120 minutes zmaniyos or 1/6th of the day before sunrise or sea level sunrise (depending on the ZmanimCalendar.isUseElevation() setting). This is based on a 24-minute mil so the time for 5 mil is 120 minutes which is 1/6th of a day (12 * 60 / 6 = 120). The day is calculated from sea level sunrise to sea level sunset or sunrise to sunset (depending on the ZmanimCalendar.isUseElevation(). The actual calculation used is AstronomicalCalendar.getSunrise() - (ZmanimCalendar.getShaahZmanisGra() * 2). Since this time is extremely early, it should only be used lechumra, such as not eating after this time on a fast day, and not as the start time for mitzvos that can only be performed during the day.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos26Degrees

      Deprecated.
      This method should be used lechumra only (such as stopping to eat at this time on a fast day), since it returns a very early time, and if used lekula can result in doing mitzvos hayom too early according to most opinions. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns alos (dawn) calculated when the sun is 26° below the eastern geometric horizon before sunrise. This calculation is based on the same calculation of 120 minutes but uses a degree-based calculation instead of 120 exact minutes. This calculation is based on the position of the sun 120 minutes before sunrise in Jerusalem around the equinox / equilux, which calculates to 26° below geometric zenith. Since this time is extremely early, it should only be used lechumra only, such as not eating after this time on a fast day, and not as the start time for mitzvos that can only be performed during the day.
      Returns:
      the Date representing alos. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos18Degrees

      A method to return alos (dawn) calculated when the sun is 18° below the eastern geometric horizon before sunrise.
      Returns:
      the Date representing alos. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos19Degrees

      A method to return alos (dawn) calculated when the sun is 19° below the eastern geometric horizon before sunrise. This is the Rambam's alos according to Rabbi Moshe Kosower's Maaglei Tzedek, page 88, Ayeles Hashachar Vol. I, page 12, Yom Valayla Shel Torah, Ch. 34, p. 222 and Rabbi Yaakov Shakow's Luach Ikvei Hayom.
      Returns:
      the Date representing alos. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos19Point8Degrees

      Method to return alos (dawn) calculated when the sun is 19.8° below the eastern geometric horizon before sunrise. This calculation is based on the same calculation of 90 minutes but uses a degree-based calculation instead of 90 exact minutes. This calculation is based on the position of the sun 90 minutes before sunrise in Jerusalem around the equinox / equilux, which calculates to 19.8° below geometric zenith.
      Returns:
      the Date representing alos. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAlos16Point1Degrees

      Method to return alos (dawn) calculated when the sun is 16.1° below the eastern geometric horizon before sunrise. This calculation is based on the same calculation of 72 minutes but uses a degree-based calculation instead of 72 exact minutes. This calculation is based on the position of the sun 72 minutes before sunrise in Jerusalem around the equinox / equilux, which calculates to 16.1° below geometric zenith.
      Returns:
      the Date representing alos. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMisheyakir11Point5Degrees

      This method returns misheyakir based on the position of the sun when it is 11.5° below geometric zenith (90°). This calculation is used for calculating misheyakir according to some opinions. This calculation is based on the position of the sun 52 minutes before sunrise in Jerusalem around the equinox / equilux, which calculates to 11.5° below geometric zenith.
      Returns:
      the Date of misheyakir. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      recalculate.
    • getMisheyakir11Degrees

      This method returns misheyakir based on the position of the sun when it is 11° below geometric zenith (90°). This calculation is used for calculating misheyakir according to some opinions. This calculation is based on the position of the sun 48 minutes before sunrise in Jerusalem around the equinox / equilux, which calculates to 11° below geometric zenith.
      Returns:
      If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMisheyakir10Point2Degrees

      This method returns misheyakir based on the position of the sun when it is 10.2° below geometric zenith (90°). This calculation is used for calculating misheyakir according to some opinions. This calculation is based on the position of the sun 45 minutes before sunrise in Jerusalem around the equinox which calculates to 10.2° below geometric zenith.
      Returns:
      the Date of misheyakir. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMisheyakir7Point65Degrees

      This method returns misheyakir based on the position of the sun when it is 7.65° below geometric zenith (90°). The degrees are based on a 35/36 minute zman around the equinox / equilux, when the neshef (twilight) is the shortest. This time is based on Rabbi Moshe Feinstein who writes in Ohr Hachaim Vol. 4, Ch. 6) that misheyakir in New York is 35-40 minutes before sunrise, something that is a drop less than 8°. Rabbi Yisroel Taplin in Zmanei Yisrael (page 117) notes that Rabbi Yaakov Kamenetsky stated that it is not less than 36 minutes before sunrise (maybe it is 40 minutes). Sefer Yisrael Vehazmanim (p. 7) quotes the Tamar Yifrach in the name of the Satmar Rov that one should be stringent not consider misheyakir before 36 minutes. This is also the accepted minhag in Lakewood that is used in the Yeshiva. This follows the opinion of Rabbi Shmuel Kamenetsky who provided the time of 35/36 minutes, but did not provide a degree-based time. Since this zman depends on the level of light, Rabbi Yaakov Shakow presented this degree-based calculations to Rabbi Shmuel Kamenetsky who agreed to them.
      Returns:
      the Date of misheyakir. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMisheyakir9Point5Degrees

      This method returns misheyakir based on the position of the sun when it is 9.5° below geometric zenith (90°). This calculation is based on Rabbi Dovid Kronglass's Calculation of 45 minutes in Baltimore as mentioned in Divrei Chachamim No. 24 brought down by the Birur Halacha, Tinyana, Ch. 18. This calculates to 9.5°. Also see Rabbi Yaakov Yitzchok Neiman in Kovetz Eitz Chaim Vol. 9, p. 202 that the Vya'an Yosef did not want to rely on times earlier than 45 minutes in New York. This zman is also used in the calendars published by Rabbi Hershel Edelstein. As mentioned in Yisroel Vehazmanim, Rabbi Edelstein who was given the 45 minute zman by Rabbi Bick. The calendars published by the Edot Hamizrach communities also use this zman. This also follows the opinion of Rabbi Shmuel Kamenetsky who provided the time of 36 and 45 minutes, but did not provide a degree-based time. Since this zman depends on the level of light, Rabbi Yaakov Shakow presented these degree-based times to Rabbi Shmuel Kamenetsky who agreed to them.
      Returns:
      the Date of misheyakir. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA19Point8Degrees

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 19.8° before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 19.8° below sunrise or sunset. This returns the time of 3 * getShaahZmanis19Point8Degrees() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA16Point1Degrees

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 16.1° before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 16.1° below sunrise or sunset. This returns the time of 3 * getShaahZmanis16Point1Degrees() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA18Degrees

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 18° before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 18° below sunrise or sunset. This returns the time of 3 * getShaahZmanis18Degrees() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA72Minutes

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes before sunrise to nightfall of 72 minutes after sunset. This returns the time of 3 * getShaahZmanis72Minutes() after dawn. This class returns an identical time to ZmanimCalendar.getSofZmanShmaMGA() and is repeated here for clarity.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA72MinutesZmanis

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes zmaniyos, or 1/10th of the day before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes zmaniyos, or 1/10th of the day before sea level sunrise to nightfall of 72 minutes zmaniyos after sea level sunset. This returns the time of 3 * getShaahZmanis72MinutesZmanis() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA90Minutes

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 90 minutes before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 90 minutes before sunrise to nightfall of 90 minutes after sunset. This returns the time of 3 * getShaahZmanis90Minutes() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA90MinutesZmanis

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 90 minutes zmaniyos before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 90 minutes zmaniyos before sunrise to nightfall of 90 minutes zmaniyos after sunset. This returns the time of 3 * getShaahZmanis90MinutesZmanis() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA96Minutes

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 96 minutes before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 96 minutes before sunrise to nightfall of 96 minutes after sunset. This returns the time of 3 * getShaahZmanis96Minutes() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA96MinutesZmanis

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 96 minutes zmaniyos before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 96 minutes zmaniyos before sunrise to nightfall of 96 minutes zmaniyos after sunset. This returns the time of 3 * getShaahZmanis96MinutesZmanis() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShma3HoursBeforeChatzos

      This method returns the latest zman krias shema (time to recite Shema in the morning) calculated as 3 hours (regular clock hours and not shaos zmaniyos) before ZmanimCalendar.getChatzos(). Generally known as part of the "Komarno" zmanim after Rav Yitzchak Eizik of Komarno, a proponent of this calculation, it actually predates him a lot. It is the opinion of the Shach in the Nekudas Hakesef (Yoreh Deah 184), Rav Moshe Lifshitz in his commentary Lechem Mishneh on Brachos 1:2. It is next brought down about 100 years later by the Yaavetz (in his siddur, Mor Uktziah Orach Chaim 1, Lechem Shamayim, Brachos 1:2 and She'elos Yaavetz vol. 1 no. 40), Rav Yitzchak Eizik of Komarno in the Ma'aseh Oreg on Mishnayos Brachos 11:2, Shevus Yaakov, Chasan Sofer and others. See Yisrael Vehazmanim vol. 1 7:3, page 55 - 62. A variant of this calculation getSofZmanShmaFixedLocal() uses fixed local chatzos for calculating this type of zman.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA120Minutes

      This method returns the latest zman krias shema (time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) based on alos being 120 minutes or 1/6th of the day before sunrise. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 120 minutes before sunrise to nightfall of 120 minutes after sunset. This returns the time of 3 getShaahZmanis120Minutes() after dawn. This is an extremely early zman that is very much a chumra.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaAlos16Point1ToSunset

      This method returns the latest zman krias shema (time to recite Shema in the morning) based on the opinion that the day starts at alos 16.1° and ends at sea level sunset. This is the opinion of the חידושי וכללות הרז״ה and the מנורה הטהורה as mentioned by Yisrael Vehazmanim vol 1, sec. 7, ch. 3 no. 16. Three shaos zmaniyos are calculated based on this day and added to alos to reach this time. This time is 3 shaos zmaniyos (solar hours) after dawn based on the opinion that the day is calculated from a alos 16.1° to sea level sunset. Note: Based on this calculation chatzos will not be at midday and ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim() will be ignored.
      Returns:
      the Date of the latest zman krias shema based on this day. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaAlos16Point1ToTzaisGeonim7Point083Degrees

      This method returns the latest zman krias shema (time to recite Shema in the morning) based on the opinion that the day starts at alos 16.1° and ends at tzais 7.083°. 3 shaos zmaniyos are calculated based on this day and added to alos to reach this time. This time is 3 shaos zmaniyos (temporal hours) after alos 16.1° based on the opinion that the day is calculated from a alos 16.1° to tzais 7.083°. Note: Based on this calculation chatzos will not be at midday and ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim() will be ignored.
      Returns:
      the Date of the latest zman krias shema based on this calculation. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaKolEliyahu

      Deprecated.
      As per a conversation Rabbi Yisroel Twerski had with Rabbi Harfenes, this zman published in the Yisrael Vehazmanim was based on a misunderstanding and should not be used. This deprecated method will be removed (likely in v3.0) pending confirmation from Rabbi Harfenes.
      From the GRA in Kol Eliyahu on Berachos #173 that states that zman krias shema is calculated as half the time from sea level sunrise to fixed local chatzos. The GRA himself seems to contradict this when he stated that zman krias shema is 1/4 of the day from sunrise to sunset. See Sarah Lamoed #25 in Yisroel Vehazmanim Vol. III page 1016.
      Returns:
      the Date of the latest zman krias shema based on this calculation. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA19Point8Degrees

      This method returns the latest zman tfila (time to recite the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 19.8° before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 19.8° below sunrise or sunset. This returns the time of 4 * getShaahZmanis19Point8Degrees() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA16Point1Degrees

      This method returns the latest zman tfila (time to recite the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 16.1° before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 16.1° below sunrise or sunset. This returns the time of 4 * getShaahZmanis16Point1Degrees() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA18Degrees

      This method returns the latest zman tfila (time to recite the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 18° before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 18° below sunrise or sunset. This returns the time of 4 * getShaahZmanis18Degrees() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA72Minutes

      This method returns the latest zman tfila (time to recite the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes before sunrise to nightfall of 72 minutes after sunset. This returns the time of 4 * getShaahZmanis72Minutes() after dawn. This class returns an identical time to ZmanimCalendar.getSofZmanTfilaMGA() and is repeated here for clarity.
      Returns:
      the Date of the latest zman tfila. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA72MinutesZmanis

      This method returns the latest zman tfila (time to the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes zmaniyos before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes zmaniyos before sunrise to nightfall of 72 minutes zmaniyos after sunset. This returns the time of 4 * getShaahZmanis72MinutesZmanis() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA90Minutes

      This method returns the latest zman tfila (time to recite the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 90 minutes before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 90 minutes before sunrise to nightfall of 90 minutes after sunset. This returns the time of 4 * getShaahZmanis90Minutes() after dawn.
      Returns:
      the Date of the latest zman tfila. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA90MinutesZmanis

      This method returns the latest zman tfila (time to the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 90 minutes zmaniyos before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 90 minutes zmaniyos before sunrise to nightfall of 90 minutes zmaniyos after sunset. This returns the time of 4 * getShaahZmanis90MinutesZmanis() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA96Minutes

      This method returns the latest zman tfila (time to recite the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 96 minutes before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 96 minutes before sunrise to nightfall of 96 minutes after sunset. This returns the time of 4 * getShaahZmanis96Minutes() after dawn.
      Returns:
      the Date of the latest zman tfila. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA96MinutesZmanis

      This method returns the latest zman tfila (time to the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 96 minutes zmaniyos before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 96 minutes zmaniyos before sunrise to nightfall of 96 minutes zmaniyos after sunset. This returns the time of 4 * getShaahZmanis96MinutesZmanis() after dawn.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaMGA120Minutes

      This method returns the latest zman tfila (time to recite the morning prayers) according to the opinion of the Magen Avraham (MGA) based on alos being 120 minutes before sunrise . This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 120 minutes before sunrise to nightfall of 120 minutes after sunset. This returns the time of 4 * getShaahZmanis120Minutes() after dawn. This is an extremely early zman that is very much a chumra.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfila2HoursBeforeChatzos

      This method returns the latest zman tfila (time to recite the morning prayers) calculated as 2 hours before ZmanimCalendar.getChatzos(). This is based on the opinions that calculate sof zman krias shema as getSofZmanShma3HoursBeforeChatzos(). This returns the time of 2 hours before ZmanimCalendar.getChatzos().
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaGedola30Minutes

      This method returns mincha gedola calculated as 30 minutes after chatzos and not 1/2 of a shaah zmanis after chatzos as calculated by ZmanimCalendar.getMinchaGedola(java.util.Date, java.util.Date, boolean). Some use this time to delay the start of mincha in the winter when 1/2 of a shaah zmanis is less than 30 minutes. See getMinchaGedolaGreaterThan30() for a convenience method that returns the later of the 2 calculations. One should not use this time to start mincha before the standard mincha gedola. See Shulchan Aruch Orach Chayim 234:1 and the Shaar Hatziyon seif katan ches. Since this calculation is a fixed 30 minutes of regular clock time after chatzos, even if ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim() is false, this mincha gedola time will be affected by ZmanimCalendar.isUseAstronomicalChatzos() and not by ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim().
      Returns:
      the Date of 30 minutes after chatzos. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaGedola72Minutes

      This method returns the time of mincha gedola according to the Magen Avraham with the day starting 72 minutes before sunrise and ending 72 minutes after sunset. This is the earliest time to pray mincha. For more information on this see the documentation on mincha gedola. This is calculated as 6.5 solar hours after alos. The calculation used is 6.5 * getShaahZmanis72Minutes() after alos. If ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim() is set to true, the calculation will be based on 0.5 half-day based sha'ah zmanis between ZmanimCalendar.getChatzos() and ZmanimCalendar.getTzais72() after ZmanimCalendar.getChatzos().
      Returns:
      the Date of the time of mincha gedola. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaGedola16Point1Degrees

      This method returns the time of mincha gedola according to the Magen Avraham with the day starting and ending 16.1° below the horizon. This is the earliest time to pray mincha. For more information on this see the documentation on mincha gedola. This is calculated as 6.5 solar hours after alos. The calculation used is 6.5 * getShaahZmanis16Point1Degrees() after alos. If ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim() is set to true, the calculation will be based on 0.5 half-day based sha'ah zmanis between ZmanimCalendar.getChatzos() and getAlos16Point1Degrees() after ZmanimCalendar.getChatzos().
      Returns:
      the Date of the time of mincha gedola. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaGedolaAhavatShalom

      This method returns the time of mincha gedola based on the opinion of Rabbi Yaakov Moshe Hillel as published in the luach of the Bais Horaah of Yeshivat Chevrat Ahavat Shalom that mincha gedola is calculated as half a shaah zmanis after chatzos with shaos zmaniyos calculated based on a day starting 72 minutes before sunrise alos 16.1° and ending 13.5 minutes after sunset tzais 3.7°. Mincha gedola is the earliest time to pray mincha. The later of this time or 30 clock minutes after chatzos is returned. See getMinchaGedolaGreaterThan30() (though that calculation is based on mincha gedola GRA). For more information about mincha gedola see the documentation on mincha gedola. Since calculation of this zman involves chatzos that is offset from the center of the astronomical day, ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim() is N/A here.
      Returns:
      the Date of the mincha gedola. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaGedolaGreaterThan30

      FIXME check for synchronous This is a convenience method that returns the later of ZmanimCalendar.getMinchaGedola() and getMinchaGedola30Minutes(). In the winter when 1/2 of a shaah zmanis is less than 30 minutes getMinchaGedola30Minutes() will be returned, otherwise ZmanimCalendar.getMinchaGedola() will be returned. Since this calculation can be an offset of chatzos (if 30 clock minutes > 1/2 of a shaah zmanis), even if ZmanimCalendar.isUseAstronomicalChatzosForOtherZmanim() is false, this mincha time may be affected by ZmanimCalendar.isUseAstronomicalChatzos().
      Returns:
      the Date of the later of ZmanimCalendar.getMinchaGedola() and getMinchaGedola30Minutes(). If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaKetana16Point1Degrees

      This method returns the time of mincha ketana according to the Magen Avraham with the day starting and ending 16.1° below the horizon. This is the preferred earliest time to pray mincha according to the opinion of the Rambam and others. For more information on this see the documentation on mincha gedola. This is calculated as 9.5 solar hours after alos. The calculation used is 9.5 * getShaahZmanis16Point1Degrees() after alos.
      Returns:
      the Date of the time of mincha ketana. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaKetanaAhavatShalom

      This method returns the time of mincha ketana based on the opinion of Rabbi Yaakov Moshe Hillel as published in the luach of the Bais Horaah of Yeshivat Chevrat Ahavat Shalom that mincha ketana is calculated as 2.5 shaos zmaniyos before tzais 3.8° with shaos zmaniyos calculated based on a day starting at alos 16.1° and ending at tzais 3.8°. Mincha ketana is the preferred earliest time to pray mincha according to the opinion of the Rambam and others. For more information on this see the documentation on mincha ketana.
      Returns:
      the Date of the time of mincha ketana. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaKetana72Minutes

      This method returns the time of mincha ketana according to the Magen Avraham with the day starting 72 minutes before sunrise and ending 72 minutes after sunset. This is the preferred earliest time to pray mincha according to the opinion of the Rambam and others. For more information on this see the documentation on mincha gedola. This is calculated as 9.5 getShaahZmanis72Minutes() after alos. The calculation used is 9.5 * getShaahZmanis72Minutes() after alos.
      Returns:
      the Date of the time of mincha ketana. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, anull will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha60Minutes

      This method returns the time of plag hamincha according to the Magen Avraham with the day starting 60 minutes before sunrise and ending 60 minutes after sunset. This is calculated as 10.75 hours after dawn. The formula used is 10.75 getShaahZmanis60Minutes() after getAlos60().
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha72Minutes

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha according to the Magen Avraham with the day starting 72 minutes before sunrise and ending 72 minutes after sunset. This is calculated as 10.75 hours after dawn. The formula used is 10.75 getShaahZmanis72Minutes() after ZmanimCalendar.getAlos72(). Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha90Minutes

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha according to the Magen Avraham with the day starting 90 minutes before sunrise and ending 90 minutes after sunset. This is calculated as 10.75 hours after dawn. The formula used is 10.75 getShaahZmanis90Minutes() after getAlos90(). Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha96Minutes

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha according to the Magen Avraham with the day starting 96 minutes before sunrise and ending 96 minutes after sunset. This is calculated as 10.75 hours after dawn. The formula used is 10.75 getShaahZmanis96Minutes() after getAlos96(). Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha96MinutesZmanis

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha. This is calculated as 10.75 hours after dawn. The formula used is 10.75 * getShaahZmanis96MinutesZmanis() after dawn. Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getPlagHamincha90MinutesZmanis

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha. This is calculated as 10.75 hours after dawn. The formula used is 10.75 * getShaahZmanis90MinutesZmanis() after dawn. Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getPlagHamincha72MinutesZmanis

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha. This is calculated as 10.75 hours after getAlos72Zmanis(). The formula used is 10.75 * getShaahZmanis72MinutesZmanis() after dawn. Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getPlagHamincha16Point1Degrees

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha based on the opinion that the day starts at alos 16.1° and ends at tzais 16.1°. This is calculated as 10.75 hours zmaniyos after dawn. The formula used is 10.75 * getShaahZmanis16Point1Degrees() after getAlos16Point1Degrees(). Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha19Point8Degrees

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha based on the opinion that the day starts at alos 19.8° and ends at tzais 19.8°. This is calculated as 10.75 hours zmaniyos after dawn. The formula used is 10.75 * getShaahZmanis19Point8Degrees() after getAlos19Point8Degrees(). Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha26Degrees

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha based on the opinion that the day starts at alos 26° and ends at tzais 26°. This is calculated as 10.75 hours zmaniyos after dawn. The formula used is 10.75 * getShaahZmanis26Degrees() after getAlos26Degrees(). Since the zman based on an extremely early alos and a very late tzais, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHamincha18Degrees

      Deprecated.
      This method should be used lechumra only since it returns a very late time (often after shkiah), and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns the time of plag hamincha based on the opinion that the day starts at alos 18° and ends at tzais 18°. This is calculated as 10.75 hours zmaniyos after dawn. The formula used is 10.75 * getShaahZmanis18Degrees() after getAlos18Degrees(). Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagAlosToSunset

      Deprecated.
      This method should be used lechumra only and returns the time of plag hamincha based on the opinion that the day starts at alos 16.1° and ends at sunset. 10.75 shaos zmaniyos are calculated based on this day and added to alos to reach this time. This time is 10.75 shaos zmaniyos (temporal hours) after dawn based on the opinion that the day is calculated from a dawn of 16.1 degrees before sunrise to sea level sunset. This returns the time of 10.75 * the calculated shaah zmanis after dawn. Since plag by this calculation can occur after sunset, it should only be used lechumra.
      Returns:
      the Date of the plag. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagAlos16Point1ToTzaisGeonim7Point083Degrees

      This method returns the time of plag hamincha based on the opinion that the day starts at alos 16.1° and ends at tzais. 10.75 shaos zmaniyos are calculated based on this day and added to alos to reach this time. This time is 10.75 shaos zmaniyos (temporal hours) after dawn based on the opinion that the day is calculated from a dawn of 16.1 degrees before sunrise to tzais . This returns the time of 10.75 * the calculated shaah zmanis after dawn.
      Returns:
      the Date of the plag. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagAhavatShalom

      This method returns the time of plag hamincha (the earliest time that Shabbos can be started) based on the opinion of Rabbi Yaakov Moshe Hillel as published in the luach of the Bais Horaah of Yeshivat Chevrat Ahavat Shalom that that plag hamincha is calculated as 1.25 shaos zmaniyos before tzais 3.8° with shaos zmaniyos calculated based on a day starting at alos 16.1° and ending at tzais 3.8°.
      Returns:
      the Date of the plag. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getBainHashmashosRT13Point24Degrees

      Method to return the beginning of bain hashmashos of Rabbeinu Tam calculated when the sun is 13.24° below the western geometric horizon (90°) after sunset. This calculation is based on the same calculation of bain hashmashos Rabbeinu Tam 58.5 minutes but uses a degree-based calculation instead of 58.5 exact minutes. This calculation is based on the position of the sun 58.5 minutes after sunset in Jerusalem around the equinox / equilux, which calculates to 13.24° below geometric zenith. NOTE: As per Yisrael Vehazmanim Vol. III page 1028, No. 50, a dip of slightly less than 13° should be used. Calculations show that the proper dip to be 13.2456° (truncated to 13.24 that provides about 1.5 second earlier (lechumra) time) below the horizon at that time. This makes a difference of 1 minute and 10 seconds in Jerusalem during the Equinox, and 1 minute 29 seconds during the solstice as compared to the proper 13.24° versus 13°. For NY during the solstice, the difference is 1 minute 56 seconds.
      Returns:
      the Date of the sun being 13.24° below geometric zenith (90°). If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      recalculate the above based on equilux/equinox calculations.
    • getBainHasmashosRT13Point24Degrees

      Deprecated.
      Misspelled method name that should be getBainHashmashosRT13Point24Degrees().
      Returns:
      the properly spelled version.
    • getBainHashmashosRT58Point5Minutes

      This method returns the beginning of Bain hashmashos of Rabbeinu Tam calculated as a 58.5 minute offset after sunset. bain hashmashos is 3/4 of a mil before tzais or 3 1/4 mil after sunset. With a mil calculated as 18 minutes, 3.25 * 18 = 58.5 minutes.
      Returns:
      the Date of 58.5 minutes after sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getBainHasmashosRT58Point5Minutes

      Deprecated.
      Misspelled method name that should be getBainHashmashosRT58Point5Minutes().
      Returns:
      the properly spelled version.
    • getBainHashmashosRT13Point5MinutesBefore7Point083Degrees

      This method returns the beginning of bain hashmashos based on the calculation of 13.5 minutes (3/4 of an 18-minute mil) before shkiah calculated as 7.083°.
      Returns:
      the Date of the bain hashmashos of Rabbeinu Tam in this calculation. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getBainHasmashosRT13Point5MinutesBefore7Point083Degrees

      Deprecated.
      Misspelled method name that should be getBainHashmashosRT13Point5MinutesBefore7Point083Degrees().
      Returns:
      the properly spelled version.
    • getBainHashmashosRT2Stars

      This method returns the beginning of bain hashmashos of Rabbeinu Tam calculated according to the opinion of the Divrei Yosef (see Yisrael Vehazmanim) calculated 5/18th (27.77%) of the time between alos (calculated as 19.8° before sunrise) and sunrise. This is added to sunset to arrive at the time for bain hashmashos of Rabbeinu Tam.
      Returns:
      the Date of bain hashmashos of Rabbeinu Tam for this calculation. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getBainHasmashosRT2Stars

      Deprecated.
      Misspelled method name that should be getBainHashmashosRT2Stars().
      Returns:
      the properly spelled version.
    • getBainHashmashosYereim18Minutes

      This method returns the beginning of bain hashmashos (twilight) according to the Yereim (Rabbi Eliezer of Metz) calculated as 18 minutes or 3/4 of a 24-minute mil before sunset. According to the Yereim, bain hashmashos starts 3/4 of a mil before sunset and tzais or nightfall starts at sunset.
      Returns:
      the Date of 18 minutes before sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getBainHasmashosYereim18Minutes

      Deprecated.
      Misspelled method name that should be getBainHashmashosYereim18Minutes().
      Returns:
      the properly spelled version.
    • getBainHashmashosYereim3Point05Degrees

      This method returns the beginning of bain hashmashos (twilight) according to the Yereim (Rabbi Eliezer of Metz) calculated as the sun's position 3.05° above the horizon around the equinox / equilux, its position 18 minutes or 3/4 of an 24-minute mil before sunset. According to the Yereim, bain hashmashos starts 3/4 of a mil before sunset and tzais or nightfall starts at sunset. Note that lechumra (of about 14 seconds) a refraction value of 0.5166° as opposed to the traditional 0.566° is used. This is more inline with the actual refraction in Eretz Yisrael and is brought down by Rabbi Yedidya Manet in his Zmanei Halacha Lema’aseh (p. 11). That is the first source that I am aware of that calculates degree-based Yereim zmanim. The 0.5166° refraction is also used by the Luach Itim Lebinah. Calculating the Yereim's bain hashmashos using 18-minute based degrees is also suggested in the upcoming 8th edition of the zmanim Kehilchasam. For more details, see the article The Yereim’s Bein Hashmashos.
      Returns:
      the Date of the sun's position 3.05° minutes before sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      recalculate based on equinox/equilux
    • getBainHasmashosYereim3Point05Degrees

      Deprecated.
      Misspelled method name that should be getBainHashmashosYereim3Point05Degrees().
      Returns:
      the properly spelled version.
    • getBainHashmashosYereim16Point875Minutes

      This method returns the beginning of bain hashmashos (twilight) according to the Yereim (Rabbi Eliezer of Metz) calculated as 16.875 minutes or 3/4 of a 22.5-minute mil before sunset. According to the Yereim, bain hashmashos starts 3/4 of a mil before sunset and tzais or nightfall starts at sunset.
      Returns:
      the Date of 16.875 minutes before sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getBainHasmashosYereim16Point875Minutes

      Deprecated.
      Misspelled method name that should be getBainHashmashosYereim16Point875Minutes().
      Returns:
      the properly spelled version.
    • getBainHashmashosYereim2Point8Degrees

      This method returns the beginning of bain hashmashos (twilight) according to the Yereim (Rabbi Eliezer of Metz) calculated as the sun's position 2.8° above the horizon around the equinox / equilux, its position 16.875 minutes or 3/4 of an 18-minute mil before sunset. According to the Yereim, bain hashmashos starts 3/4 of a mil before sunset and tzais or nightfall starts at sunset. Details, including how the degrees were calculated can be seen in the documentation of getBainHashmashosYereim3Point05Degrees().
      Returns:
      the Date of the sun's position 2.8° minutes before sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getBainHasmashosYereim2Point8Degrees

      Deprecated.
      Misspelled method name that should be getBainHashmashosYereim2Point8Degrees().
      Returns:
      the properly spelled version.
    • getBainHashmashosYereim13Point5Minutes

      This method returns the beginning of bain hashmashos (twilight) according to the Yereim (Rabbi Eliezer of Metz) calculated as 13.5 minutes or 3/4 of an 18-minute mil before sunset. According to the Yereim, bain hashmashos starts 3/4 of a mil before sunset and tzais or nightfall starts at sunset.
      Returns:
      the Date of 13.5 minutes before sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getBainHasmashosYereim13Point5Minutes

      Deprecated.
      Misspelled method name that should be getBainHashmashosYereim13Point5Minutes().
      Returns:
      the properly spelled version.
    • getBainHashmashosYereim2Point1Degrees

      This method returns the beginning of bain hashmashos according to the Yereim (Rabbi Eliezer of Metz) calculated as the sun's position 2.1° above the horizon around the equinox / equilux in Yerushalayim, its position 13.5 minutes or 3/4 of an 18-minute mil before sunset. According to the Yereim, bain hashmashos starts 3/4 of a mil before sunset and tzais or nightfall starts at sunset. Details, including how the degrees were calculated can be seen in the documentation of getBainHashmashosYereim3Point05Degrees().
      Returns:
      the Date of the sun's position 2.1° minutes before sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getBainHasmashosYereim2Point1Degrees

      Deprecated.
      Misspelled method name that should be getBainHashmashosYereim2Point1Degrees().
      Returns:
      the properly spelled version.
    • getTzaisGeonim3Point7Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated at the sun's position at 3.7° below the western horizon.
      Returns:
      the Date representing the time when the sun is 3.7° below sea level.
      See Also:
    • getTzaisGeonim3Point8Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated at the sun's position at 3.8° below the western horizon.
      Returns:
      the Date representing the time when the sun is 3.8° below sea level.
      See Also:
    • getTzaisGeonim5Point95Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated at the sun's position at 5.95° below the western horizon.
      Returns:
      the Date representing the time when the sun is 5.95° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisGeonim3Point65Degrees

      Deprecated.
      This will be removed in v3.0.0 since calculations show that this time is earlier than 13.5 minutes at the around the equinox / equilux in Jerusalem.
      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated as 3/4 of a mil based on an 18-minute mil, or 13.5 minutes. It is the sun's position at 3.65° below the western horizon. This is a very early zman and should not be relied on without Rabbinical guidance.
      Returns:
      the Date representing the time when the sun is 3.65° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisGeonim3Point676Degrees

      Deprecated.
      This will be removed in v3.0.0 since calculations show that this time is earlier than 13.5 minutes at the around the equinox / equilux in Jerusalem.
      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated as 3/4 of a mil based on an 18-minute mil, or 13.5 minutes. It is the sun's position at 3.676° below the western horizon based on the calculations of Stanley Fishkind. This is a very early zman and should not be relied on without Rabbinical guidance.
      Returns:
      the Date representing the time when the sun is 3.676° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisGeonim4Point61Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated as 3/4 of a mil based on a 24-minute mil, or 18 minutes. It is the sun's position at 4.61° below the western horizon. This is a very early zman and should not be relied on without Rabbinical guidance.
      Returns:
      the Date representing the time when the sun is 4.61° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisGeonim4Point37Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated as 3/4 of a mil, based on a 22.5-minute mil, or 16 7/8 minutes. It is the sun's position at 4.37° below the western horizon. This is a very early zman and should not be relied on without Rabbinical guidance.
      Returns:
      the Date representing the time when the sun is 4.37° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisGeonim5Point88Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated as 3/4 of a 24-minute mil, based on a mil being 24 minutes, and is calculated as 18 + 2 + 4 for a total of 24 minutes. It is the sun's position at 5.88° below the western horizon. This is a very early zman and should not be relied on without Rabbinical guidance.
      Returns:
      the Date representing the time when the sun is 5.88° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      Additional detailed documentation needed.
    • getTzaisGeonim4Point8Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated as 3/4 of a mil based on the sun's position at 4.8° below the western horizon. This is based on Rabbi Leo Levi's calculations. This is a very early zman and should not be relied on without Rabbinical guidance.
      Returns:
      the Date representing the time when the sun is 4.8° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      Additional documentation needed.
    • getTzaisGeonim6Point45Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim as calculated by Rabbi Yechiel Michel Tucazinsky. It is based on of the position of the sun no later than 31 minutes after sunset in Jerusalem the height of the summer solstice and is 28 minutes after shkiah around the equinox / equilux. This computes to 6.45° below the western horizon.
      Returns:
      the Date representing the time when the sun is 6.45° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      Additional documentation details needed.
    • getTzaisGeonim7Point083Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated when the sun's position 7.083° (or 7° 5′) below the western horizon. This is often referred to as 7°5' or 7° and 5 minutes. This calculation is based on the observation of 3 medium-sized stars by Dr. Baruch (Berthold) Cohn in his luach Tabellen enthaltend die Zeitangaben für den Beginn der Nacht und des Tages für die Breitengrade + 66 bis -38 published in Strasbourg, France in 1899. This calendar was very popular in Europe, and many other calendars based their time on it. Rav Dovid Tzvi Hoffman in his Sh"Ut Melamed Leho'il in an exchange of letters with Baruch Cohn in Orach Chaim 30 agreed to this zman (page 36), as did the Sh"Ut Bnei Tziyon and the Tenuvas Sadeh. It is very close to the time of the Mekor Chesed of the Sefer chasidim. It is close to the position of the sun 30 minutes after sunset in Jerusalem around the equinox / equilux, but not Exactly. The actual position of the sun 30 minutes after sunset in Jerusalem at the equilux is 7.205° and 7.199° at the equinox. See Hazmanim Bahalacha vol 2, pages 520-521 for more details.
      Returns:
      the Date representing the time when the sun is 7.083° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisGeonim7Point67Degrees

      This method returns tzais (nightfall) based on the opinion of the Geonim calculated as 45 minutes after sunset during the summer solstice in New York, when the neshef (twilight) is the longest. The sun's position at this time computes to 7.75° below the western horizon. See Igros Moshe Even Haezer 4, Ch. 4 (regarding tzais for krias Shema). It is also mentioned in Rabbi Heber's Shaarei Zmanim on in chapter 10 (page 87) and chapter 12 (page 108). Also see the time of 45 minutes in Rabbi Simcha Bunim Cohen's The radiance of Shabbos as the earliest zman for New York. This zman is also listed in the Divrei Shalom Vol. III, chapter 75, and Bais Av"i Vol. III, chapter 117. This zman is also listed in the Divrei Shalom etc. chapter 177 (FIXME - could not be located). Since this zman depends on the level of light, Rabbi Yaakov Shakow presented this degree-based calculation to Rabbi Rabbi Shmuel Kamenetsky who agreed to it.
      Returns:
      the Date representing the time when the sun is 7.67° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      add hyperlinks to source of Divrei Shalom once it is located.
    • getTzaisGeonim8Point5Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated at the sun's position at 8.5° below the western horizon.
      Returns:
      the Date representing the time when the sun is 8.5° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisGeonim9Point3Degrees

      This method returns the tzais (nightfall) based on the calculations used in the Luach Itim Lebinah as the stringent time for tzais. It is calculated at the sun's position at 9.3° below the western horizon.
      Returns:
      the Date representing the time when the sun is 9.3° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getTzaisGeonim9Point75Degrees

      This method returns the tzais (nightfall) based on the opinion of the Geonim calculated as 60 minutes after sunset around the equinox / equilux, the day that a solar hour is 60 minutes in New York. The sun's position at this time computes to 9.75° below the western horizon. This is the opinion of Rabbi Eliyahu Henkin. This also follows the opinion of Rabbi Shmuel Kamenetsky. Rabbi Yaakov Shakow presented these degree-based times to Rabbi Shmuel Kamenetsky who agreed to them.
      Returns:
      the Date representing the time when the sun is 9.75° below sea level. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      recalculate based on equinox / equilux.
    • getTzais60

      public Date getTzais60()
      This method returns the tzais (nightfall) based on the opinion of the Chavas Yair and Divrei Malkiel that the time to walk the distance of a mil is 15 minutes, for a total of 60 minutes for 4 mil after sea level sunset. See detailed documentation explaining the 60 minute concept at getAlos60().
      Returns:
      the Date representing 60 minutes after sea level sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzaisAteretTorah

      This method returns tzais usually calculated as 40 minutes (configurable to any offset via setAteretTorahSunsetOffset(double)) after sunset. Please note that Chacham Yosef Harari-Raful of Yeshivat Ateret Torah who uses this time, does so only for calculating various other zmanei hayom such as Sof Zman Krias Shema and Plag Hamincha. His calendars do not publish a zman for Tzais. It should also be noted that Chacham Harari-Raful provided a 25 minute zman for Israel. This API uses 40 minutes year round in any place on the globe by default. This offset can be changed by calling setAteretTorahSunsetOffset(double).
      Returns:
      the Date representing 40 minutes (configurable via setAteretTorahSunsetOffset(double)) after sea level sunset. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getAteretTorahSunsetOffset

      public double getAteretTorahSunsetOffset()
      Returns the offset in minutes after sunset used to calculate tzais based on the calculations of Chacham Yosef Harari-Raful of Yeshivat Ateret Torah calculations. The default value is 40 minutes. This affects most zmanim, since almost all zmanim use subset as part of their calculation.
      Returns:
      the number of minutes after sunset for Tzait.
      See Also:
    • setAteretTorahSunsetOffset

      public void setAteretTorahSunsetOffset(double ateretTorahSunsetOffset)
      Allows setting the offset in minutes after sunset for the Ateret Torah zmanim. The default if unset is 40 minutes. Chacham Yosef Harari-Raful of Yeshivat Ateret Torah uses 40 minutes globally with the exception of Israel where a 25-minute offset is used. This 40 minute (or any other) offset can be overridden by this method. This offset impacts all Ateret Torah zmanim.
      Parameters:
      ateretTorahSunsetOffset - the number of minutes after sunset to use as an offset for the Ateret Torah tzais
      See Also:
    • getSofZmanShmaAteretTorah

      This method returns the latest zman krias shema (time to recite Shema in the morning) based on the calculation of Chacham Yosef Harari-Raful of Yeshivat Ateret Torah, that the day starts 1/10th of the day before sunrise and is usually calculated as ending 40 minutes after sunset (configurable to any offset via setAteretTorahSunsetOffset(double)). shaos zmaniyos are calculated based on this day and added to alos to reach this time. This time is 3 shaos zmaniyos (temporal hours) after alos 72 zmaniyos. Note: Based on this calculation chatzos will not be at midday.
      Returns:
      the Date of the latest zman krias shema based on this calculation. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaAteretTorah

      This method returns the latest zman tfila (time to recite the morning prayers) based on the calculation of Chacham Yosef Harari-Raful of Yeshivat Ateret Torah, that the day starts 1/10th of the day before sunrise and is usually calculated as ending 40 minutes after sunset (configurable to any offset via setAteretTorahSunsetOffset(double)). shaos zmaniyos are calculated based on this day and added to alos to reach this time. This time is 4 * shaos zmaniyos (temporal hours) after alos 72 zmaniyos. Note: Based on this calculation chatzos will not be at midday.
      Returns:
      the Date of the latest zman krias shema based on this calculation. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilahAteretTorah

      Deprecated.
      misspelled method name (all other methods spell tfila without an H) to be removed in 3.0.0.
      Returns:
      the Date of the latest zman krias shema based on this calculation. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaGedolaAteretTorah

      This method returns the time of mincha gedola based on the calculation of Chacham Yosef Harari-Raful of Yeshivat Ateret Torah, that the day starts 1/10th of the day before sunrise and is usually calculated as ending 40 minutes after sunset (configurable to any offset via setAteretTorahSunsetOffset(double)). This is the preferred earliest time to pray mincha according to the opinion of the Rambam and others. For more information on this see the documentation on mincha gedola. This is calculated as 6.5 solar hours after alos. The calculation used is 6.5 * getShaahZmanisAteretTorah() after alos.
      Returns:
      the Date of the time of mincha gedola. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaKetanaAteretTorah

      This method returns the time of mincha ketana based on the calculation of Chacham Yosef Harari-Raful of Yeshivat Ateret Torah, that the day starts 1/10th of the day before sunrise and is usually calculated as ending 40 minutes after sunset (configurable to any offset via setAteretTorahSunsetOffset(double)). This is the preferred earliest time to pray mincha according to the opinion of the Rambam and others. For more information on this see the documentation on mincha gedola. This is calculated as 9.5 solar hours after alos. The calculation used is 9.5 * getShaahZmanisAteretTorah() after alos.
      Returns:
      the Date of the time of mincha ketana. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHaminchaAteretTorah

      This method returns the time of plag hamincha based on the calculation of Chacham Yosef Harari-Raful of Yeshivat Ateret Torah, that the day starts 1/10th of the day before sunrise and is usually calculated as ending 40 minutes after sunset (configurable to any offset via setAteretTorahSunsetOffset(double)). shaos zmaniyos are calculated based on this day and added to alos to reach this time. This time is 10.75 shaos zmaniyos (temporal hours) after dawn.
      Returns:
      the Date of the plag. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais72Zmanis

      Method to return tzais (dusk) calculated as 72 minutes zmaniyos, or 1/10th of the day after sea level sunset. This is the way that the Minchas Cohen in Ma'amar 2:4 calculates Rebbeinu Tam's time of tzeis. It should be noted that this calculation results in the shortest time from sunset to tzais being during the winter solstice, the longest at the summer solstice and 72 clock minutes at the equinox. This does not match reality, since there is no direct relationship between the length of the day and twilight. The shortest twilight is during the equinox, the longest is during the summer solstice, and in the winter with the shortest daylight, the twilight period is longer than during the equinoxes.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getZmanisBasedOffset

      private Date getZmanisBasedOffset(double hours)
      A utility method to return alos (dawn) or tzais (dusk) based on a fractional day offset.
      Parameters:
      hours - the number of shaos zmaniyos (temporal hours) before sunrise or after sunset that defines dawn or dusk. If a negative number is passed in, it will return the time of alos (dawn) (subtracting the time from sunrise) and if a positive number is passed in, it will return the time of tzais (dusk) (adding the time to sunset). If 0 is passed in, a null will be returned (since we can't tell if it is sunrise or sunset based).
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. A null will also be returned if 0 is passed in, since we can't tell if it is sunrise or sunset based. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getTzais90Zmanis

      Method to return tzais (dusk) calculated using 90 minutes zmaniyos or 1/8th of the day after sea level sunset. This time is known in Yiddish as the achtel (an eighth) zman.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais96Zmanis

      Method to return tzais (dusk) calculated using 96 minutes zmaniyos or 1/7.5 of the day after sea level sunset.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais90

      public Date getTzais90()
      Method to return tzais (dusk) calculated as 90 minutes after sea level sunset. This method returns tzais (nightfall) based on the opinion of the Magen Avraham that the time to walk the distance of a mil according to the Rambam's opinion is 18 minutes, for a total of 90 minutes based on the opinion of Ula who calculated tzais as 5 mil after sea level shkiah (sunset). A similar calculation getTzais19Point8Degrees() uses solar position calculations based on this time.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais120

      Deprecated.
      This method should be used lechumra only since it returns a very late time, and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns tzais (nightfall) based on the calculations of Rav Chaim Naeh that the time to walk the distance of a mil according to the Rambam's opinion is 2/5 of an hour (24 minutes) for a total of 120 minutes based on the opinion of Ula who calculated tzais as 5 mil after sea level shkiah (sunset). A similar calculation getTzais26Degrees() uses degree-based calculations based on this 120 minute calculation. Since the zman is extremely late and at a point that is long past the 18° point where the darkest point is reached, it should only be used lechumra, such as delaying the start of nighttime mitzvos.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar. documentation.
      See Also:
    • getTzais120Zmanis

      Deprecated.
      This method should be used lechumra only since it returns a very late time, and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns tzais (dusk) calculated using 120 minutes zmaniyos after sea level sunset. Since the zman is extremely late and at a time when the sun is well below the 18° point (scientifically the darkest point) in most places on the globe, it should only be used lechumra, such as delaying the start of nighttime mitzvos.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais16Point1Degrees

      This calculates the time of tzais at the point when the sun is 16.1° below the horizon. This is the sun's dip below the horizon 72 minutes after sunset according Rabbeinu Tam's calculation of tzais around the equinox / equilux in Jerusalem. The question of equinox VS equilux is complex, with Rabbi Meir Posen in the Ohr Meir of the opinion that the equilux should be used. See Yisrael Vehazmanim vol I, 34:1:4. Rabbi Yedidya Manet in his Zmanei Halacha Lema'aseh (4th edition part 2, pages and 22 and 24) and Rabbi Yonah Metzbuch (in a letter published by Rabbi Manet) are of the opinion that the astronomical equinox should be used. The difference adds up to about 9 seconds, too trivial to make much of a difference. For information on how this is calculated see the comments on getAlos16Point1Degrees().
      Returns:
      the Date representing the time. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais26Degrees

      Deprecated.
      This method should be used lechumra only since it returns a very late time, and if used lekula can result in chillul Shabbos etc. There is no current plan to remove this method from the API, and this deprecation is intended to alert developers of the danger of using it.
      This method should be used lechumra only and returns tzais based on when the sun is 26° below the horizon.For information on how this is calculated see the comments on getAlos26Degrees(). Since the zman is extremely late and at a point when it is long past the 18° point where the darkest point is reached, it should only be used lechumra such as delaying the start of nighttime mitzvos.
      Returns:
      the Date representing the time. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais18Degrees

      For information on how this is calculated see the comments on getAlos18Degrees()
      Returns:
      the Date representing the time. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais19Point8Degrees

      For information on how this is calculated see the comments on getAlos19Point8Degrees()
      Returns:
      the Date representing the time. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getTzais96

      public Date getTzais96()
      A method to return tzais (dusk) calculated as 96 minutes after sea level sunset. For information on how this is calculated see the comments on getAlos96().
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getFixedLocalChatzos

      A method that returns the local time for fixed chatzos. This time is noon and midnight adjusted from standard time to account for the local latitude. The 360° of the globe divided by 24 calculates to 15° per hour with 4 minutes per degree, so at a longitude of 0 , 15, 30 etc... Chatzos is at exactly 12:00 noon. This is the time of chatzos according to the Aruch Hashulchan in Orach Chaim 233:14 and Rabbi Moshe Feinstein in Igros Moshe Orach Chaim 1:24 and 2:20. Lakewood, N.J., with a longitude of -74.222, is 0.778 away from the closest multiple of 15 at -75°. This is multiplied by 4 to yield 3 minutes and 7 seconds for a chatzos of 11:56:53. This method is not tied to the theoretical 15° timezones, but will adjust to the actual timezone and Daylight saving time.
      Returns:
      the Date representing the local chatzos
      See Also:
    • getSofZmanShmaFixedLocal

      Deprecated.
      This method of calculating sof zman Shma is considered a mistaken understanding of the proper calculation of this zman in the opinion of Rav Yitzchak Silber's Sha'aos Shavos Bahalacha. On pages 316-318 he discusses Rav Yisrael Harfenes's calculations and points to his seeming agreement that using fixed local chatzos as the focal point is problematic. See Yisrael Vehazmanim page 57. While the Yisrael Vehazmanim mentions this issue in vol. 1, it was not corrected in the calculations in vol. 3 and other parts of the sefer. A competent rabbinical authority should be consulted before using this zman. Instead, the use of getSofZmanShma3HoursBeforeChatzos() should be used to calculate sof zman Tfila using 3 fixed clock hours. This will likely be removed in v3.0.
      A method that returns the latest zman krias shema (time to recite Shema in the morning) calculated as 3 clock hours before getFixedLocalChatzos(). Note that there are opinions brought down in Yisrael Vehazmanim page 57 and Rav Yitzchak Silber's Shaos Shavos Bahalacha that this calculation is a mistake and regular chatzos should be used for clock-hour calculations as opposed to fixed local chatzos. According to these opinions it should be 3 clock hours before regular chatzos as calculated in getSofZmanShma3HoursBeforeChatzos().
      Returns:
      the Date of the latest zman krias shema calculated as 3 clock hours before getFixedLocalChatzos().
      See Also:
    • getSofZmanTfilaFixedLocal

      Deprecated.
      This method of calculating sof zman Tfila is considered a mistaken understanding of the proper calculation of this zman in the opinion of Rav Yitzchak Silber's Sha'aos Shavos Bahalacha. On pages 316-318 he discusses Rav Yisrael Harfenes's calculations and points to his seeming agreement that using fixed local chatzos as the focal point is problematic. See Yisrael Vehazmanim page 57. While the Yisrael Vehazmanim mentions this issue in vol. 1, it was not corrected in the calculations in vol. 3 and other parts of the sefer. A competent rabbinical authority should be consulted before using this zman. Instead, the use of getSofZmanTfila2HoursBeforeChatzos() should be used to calculate sof zman Tfila using 2 fixed clock hours. This will likely be removed in v3.0.
      This method returns the latest zman tfila (time to recite the morning prayers) calculated as 2 hours before getFixedLocalChatzos(). See the documentation on getSofZmanShmaFixedLocal() showing differing opinions on how the zman is calculated. According to many opinions getSofZmanTfila2HoursBeforeChatzos() should be used as opposed to this zman.
      Returns:
      the Date of the latest zman tfila.
      See Also:
    • getSofZmanKidushLevanaBetweenMoldos

      Returns the latest time of Kidush Levana according to the Maharil's opinion that it is calculated as halfway between molad and molad. This adds half the 29 days, 12 hours and 793 chalakim time between molad and molad (14 days, 18 hours, 22 minutes and 666 milliseconds) to the month's molad. If the time of sof zman Kiddush Levana occurs during the day (between the alos and tzais passed in as parameters), it returns the alos passed in. If a null alos or tzais are passed to this method, the non-daytime adjusted time will be returned.
      Parameters:
      alos - the beginning of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be alos. If either the alos or tzais parameters are null, no daytime adjustment will be made.
      tzais - the end of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be alos. If either the alos or tzais parameter are null, no daytime adjustment will be made.
      Returns:
      the Date representing the moment halfway between molad and molad. If the time occurs between alos and tzais, alos will be returned. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getMoladBasedTime

      private Date getMoladBasedTime(Date moladBasedTime, Date alos, Date tzais, boolean techila)
      Returns the Date of the molad based time if it occurs on the current date. Since Kiddush Levana can only be said during the day, there are parameters to limit it to between alos and tzais. If the time occurs between alos and tzais, tzais will be returned.
      Parameters:
      moladBasedTime - the molad based time such as molad, tchilas and sof zman Kiddush Levana
      alos - optional start of day to limit molad times to the end of the night before or beginning of the next night. Ignored if either alos or tzais are null.
      tzais - optional end of day to limit molad times to the end of the night before or beginning of the next night. Ignored if either tzais or alos are null
      techila - is it the start of Kiddush Levana time or the end? If it is start roll it to the next tzais, and and if it is the end, return the end of the previous night (alos passed in). Ignored if either alos or tzais are null.
      Returns:
      the molad based time. If the zman does not occur during the current date, null will be returned.
    • getSofZmanKidushLevanaBetweenMoldos

      Returns the latest time of Kiddush Levana according to the Maharil's opinion that it is calculated as halfway between molad and molad. This adds half the 29 days, 12 hours and 793 chalakim time between molad and molad (14 days, 18 hours, 22 minutes and 666 milliseconds) to the month's molad. The sof zman Kiddush Levana will be returned even if it occurs during the day. To limit the time to between tzais and alos, see getSofZmanKidushLevanaBetweenMoldos(Date, Date).
      Returns:
      the Date representing the moment halfway between molad and molad. If the time occurs between alos and tzais, alos will be returned. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getSofZmanKidushLevana15Days

      public Date getSofZmanKidushLevana15Days(Date alos, Date tzais)
      Returns the latest time of Kiddush Levana calculated as 15 days after the molad. This is the opinion brought down in the Shulchan Aruch (Orach Chaim 426). It should be noted that some opinions hold that the Rema who brings down the opinion of the Maharil's of calculating half way between molad and molad is of the opinion that the Mechaber agrees to his opinion. Also see the Aruch Hashulchan. For additional details on the subject, see Rabbi Dovid Heber's very detailed write-up in Siman Daled (chapter 4) of Shaarei Zmanim. If the time of sof zman Kiddush Levana occurs during the day (between the alos and tzais passed in as parameters), it returns the alos passed in. If a null alos or tzais are passed to this method, the non-daytime adjusted time will be returned.
      Parameters:
      alos - the beginning of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be alos. If either the alos or tzais parameters are null, no daytime adjustment will be made.
      tzais - the end of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be alos. If either the alos or tzais parameters are null, no daytime adjustment will be made.
      Returns:
      the Date representing the moment 15 days after the molad. If the time occurs between alos and tzais, alos will be returned. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getSofZmanKidushLevana15Days

      Returns the latest time of Kiddush Levana calculated as 15 days after the molad. This is the opinion of the Shulchan Aruch (Orach Chaim 426). It should be noted that some opinions hold that the Rema who brings down the opinion of the Maharil's of calculating half way between molad and molad is of the opinion that the Mechaber agrees to his opinion. Also see the Aruch Hashulchan. For additional details on the subject, See Rabbi Dovid Heber's very detailed write-up in Siman Daled (chapter 4) of Shaarei Zmanim. The sof zman Kiddush Levana will be returned even if it occurs during the day. To limit the time to between tzais and alos, see getSofZmanKidushLevana15Days(Date, Date).
      Returns:
      the Date representing the moment 15 days after the molad. If the time occurs between alos and tzais, alos will be returned. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getTchilasZmanKidushLevana3Days

      Returns the earliest time of Kiddush Levana according to Rabbeinu Yonah's opinion that it can be said 3 days after the molad. The time will be returned even if it occurs during the day when Kiddush Levana can't be said. Use getTchilasZmanKidushLevana3Days(Date, Date) if you want to limit the time to night hours.
      Returns:
      the Date representing the moment 3 days after the molad. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getTchilasZmanKidushLevana3Days

      Returns the earliest time of Kiddush Levana according to Rabbeinu Yonah's opinion that it can be said 3 days after the molad. If the time of tchilas zman Kiddush Levana occurs during the day (between alos and tzais passed to this method) it will return the following tzais. If null is passed for either alos or tzais, the actual tchilas zman Kiddush Levana will be returned, regardless of if it is during the day or not.
      Parameters:
      alos - the beginning of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be tzais. If either the alos or tzais parameters are null, no daytime adjustment will be made.
      tzais - the end of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be tzais. If either the alos or tzais parameters are null, no daytime adjustment will be made.
      Returns:
      the Date representing the moment 3 days after the molad. If the time occurs between alos and tzais, tzais will be returned. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getZmanMolad

      public Date getZmanMolad()
      Returns the point in time of Molad as a Date Object. For the traditional day of week, hour, minute and chalakim, JewishCalendar.getMoladAsDate() and the not yet completed HebrewDateFormatter that will have formatting for this.
      Returns:
      the Date representing the moment of the molad. If the molad does not occur on this day, a null will be returned.
      See Also:
    • getMidnightLastNight

      Used by Molad based zmanim to determine if zmanim occur during the current day.
      Returns:
      previous midnight
      See Also:
    • getMidnightTonight

      Used by Molad based zmanim to determine if zmanim occur during the current day.
      Returns:
      following midnight
      See Also:
    • getTchilasZmanKidushLevana7Days

      Returns the earliest time of Kiddush Levana according to the opinions that it should not be said until 7 days after the molad. If the time of tchilas zman Kiddush Levana occurs during the day (between alos and tzais) it return the next tzais.
      Parameters:
      alos - the beginning of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be tzais. If either the alos or tzais parameters are null, no daytime adjustment will be made.
      tzais - the end of the Jewish day. If Kidush Levana occurs during the day (starting at alos and ending at tzais), the time returned will be tzais. If either the alos or tzais parameters are null, no daytime adjustment will be made.
      Returns:
      the Date representing the moment 7 days after the molad. If the time occurs between alos and tzais, tzais will be returned. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getTchilasZmanKidushLevana7Days

      Returns the earliest time of Kiddush Levana according to the opinions that it should not be said until 7 days after the molad. The time will be returned even if it occurs during the day when Kiddush Levana can't be recited. Use getTchilasZmanKidushLevana7Days(Date, Date) if you want to limit the time to night hours.
      Returns:
      the Date representing the moment 7 days after the molad regardless of it is day or night. If the zman will not occur on this day, a null will be returned.
      See Also:
    • getSofZmanAchilasChametzGRA

      This method returns the latest time one is allowed eating chametz on Erev Pesach according to the opinion of theGRA. This time is identical to the Sof zman tfilah GRA and is provided as a convenience method for those who are unaware how this zman is calculated. This time is 4 hours into the day based on the opinion of the GRA that the day is calculated from sunrise to sunset. This returns the time 4 * ZmanimCalendar.getShaahZmanisGra() after sea level sunrise. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date one is allowed eating chametz on Erev Pesach. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanAchilasChametzMGA72Minutes

      This method returns the latest time one is allowed eating chametz on Erev Pesach according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes before sunrise. This time is identical to the Sof zman tfilah MGA 72 minutes. This time is 4 shaos zmaniyos (temporal hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes before sunrise to nightfall of 72 minutes after sunset. This returns the time of 4 * ZmanimCalendar.getShaahZmanisMGA() after dawn. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time of eating chametz. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanAchilasChametzMGA72MinutesZmanis

      This method returns the latest time one is allowed eating chametz on Erev Pesach according to the opinion of the Magen Avraham (MGA) based on alos being 72 zmaniyos minutes before sunrise. This time is identical to the Sof zman tfilah MGA 72 minutes zmanis. This time is 4 shaos zmaniyos (temporal hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes zmanis before sunrise to nightfall of 72 minutes zmanis after sunset. This returns the time of 4 * getShaahZmanis72MinutesZmanis() after dawn. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time of eating chametz. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanAchilasChametzMGA16Point1Degrees

      This method returns the latest time one is allowed eating chametz on Erev Pesach according to the opinion of theMagen Avraham (MGA) based on alos being 16.1° before sunrise. This time is 4 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 16.1° below sunrise or sunset. This returns the time of 4 getShaahZmanis16Point1Degrees() after dawn. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time of eating chametz. If it is not erev Pesach or the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanBiurChametzGRA

      FIXME adjust for synchronous This method returns the latest time for burning chametz on Erev Pesach according to the opinion of the GRA. This time is 5 hours into the day based on the opinion of the GRA that the day is calculated from sunrise to sunset. This returns the time 5 * ZmanimCalendar.getShaahZmanisGra() after sea level sunrise. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time for burning chametz on Erev Pesach. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanBiurChametzMGA72Minutes

      FIXME adjust for synchronous This method returns the latest time for burning chametz on Erev Pesach according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes before sunrise. This time is 5 shaos zmaniyos (temporal hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes before sunrise to nightfall of 72 minutes after sunset. This returns the time of 5 * ZmanimCalendar.getShaahZmanisMGA() after dawn. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time for burning chametz on Erev Pesach. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanBiurChametzMGA72MinutesZmanis

      FIXME adjust for synchronous This method returns the latest time for burning chametz on Erev Pesach according to the opinion of the Magen Avraham (MGA) based on alos being 72 minutes zmanis before sunrise. This time is 5 shaos zmaniyos (temporal hours) after dawn based on the opinion of the MGA that the day is calculated from a dawn of 72 minutes zmanis before sunrise to nightfall of 72 minutes zmanis after sunset. This returns the time of 5 * getShaahZmanis72MinutesZmanis() after dawn. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time for burning chametz on Erev Pesach. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanBiurChametzMGA16Point1Degrees

      FIXME adjust for synchronous This method returns the latest time for burning chametz on Erev Pesach according to the opinion of the Magen Avraham (MGA) based on alos being 16.1° before sunrise. This time is 5 shaos zmaniyos (solar hours) after dawn based on the opinion of the MGA that the day is calculated from dawn to nightfall with both being 16.1° below sunrise or sunset. This returns the time of 5 getShaahZmanis16Point1Degrees() after dawn. If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time for burning chametz on Erev Pesach. If it is not erev Pesach or the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSunriseBaalHatanya

      A method that returns the Baal Hatanya's netz amiti (sunrise) without elevation adjustment. This forms the base for the Baal Hatanya's dawn-based calculations that are calculated as a dip below the horizon before sunrise. According to the Baal Hatanya, netz amiti, or true (halachic) sunrise, is when the top of the sun's disk is visible at an elevation similar to the mountains of Eretz Yisrael. The time is calculated as the point at which the center of the sun's disk is 1.583° below the horizon. This degree-based calculation can be found in Rabbi Shalom DovBer Levine's commentary on The Baal Hatanya's Seder Hachnasas Shabbos. From an elevation of 546 meters, the top of Har Hacarmel, the sun disappears when it is 1° 35' or 1.583° below the sea level horizon. This in turn is based on the Gemara Shabbos 35a. There are other opinions brought down by Rabbi Levine, including Rabbi Yosef Yitzchok Feigelstock who calculates it as the degrees below the horizon 4 minutes after sunset in Yerushalayim (on the equinox). That is brought down as 1.583°. This is identical to the 1° 35' zman and is probably a typo and should be 1.683°. These calculations are used by most Chabad calendars that use the Baal Hatanya's zmanim. See About Our Zmanim Calculations @ Chabad.org. Note: netz amiti is used only for calculating certain zmanim, and is intentionally unpublished. For practical purposes, daytime mitzvos like shofar and lulav should not be done until after the published time for netz / sunrise.
      Returns:
      the Date representing the exact sea level netz amiti (sunrise) time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the page.
      See Also:
    • getSunsetBaalHatanya

      A method that returns the Baal Hatanya's shkiah amiti (sunset) without elevation adjustment. This forms the base for the Baal Hatanya's dusk-based calculations that are calculated as a dip below the horizon after sunset. According to the Baal Hatanya, shkiah amiti, true (halachic) sunset, is when the top of the sun's disk disappears from view at an elevation similar to the mountains of Eretz Yisrael. This time is calculated as the point at which the center of the sun's disk is 1.583 degrees below the horizon. Note: shkiah amiti is used only for calculating certain zmanim, and is intentionally unpublished. For practical purposes, all daytime mitzvos should be completed before the published time for shkiah / sunset. For further explanation of the calculations used for the Baal Hatanya's zmanim in this library, see About Our Zmanim Calculations @ Chabad.org.
      Returns:
      the Date representing the exact sea level shkiah amiti (sunset) time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getShaahZmanisBaalHatanya

      A method that returns the Baal Hatanya's a shaah zmanis (temporal hour). This forms the base for the Baal Hatanya's day based calculations that are calculated as a 1.583° dip below the horizon after sunset. According to the Baal Hatanya, shkiah amiti, true (halachic) sunset, is when the top of the sun's disk disappears from view at an elevation similar to the mountains of Eretz Yisrael. This time is calculated as the point at which the center of the sun's disk is 1.583 degrees below the horizon. A method that returns a shaah zmanis (temporal hour) calculated based on the Baal Hatanya's netz amiti and shkiah amiti using a dip of 1.583° below the sea level horizon. This calculation divides the day based on the opinion of the Baal Hatanya that the day runs from netz amiti to shkiah amiti. The calculations are based on a day from sea level netz amiti to sea level shkiah amiti. The day is split into 12 equal parts with each one being a shaah zmanis. This method is similar to AstronomicalCalendar.getTemporalHour(), but all calculations are based on a sea level sunrise and sunset.
      Returns:
      the long millisecond length of a shaah zmanis calculated from netz amiti (sunrise) to shkiah amiti ("real" sunset). If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, Long.MIN_VALUE will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
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    • getAlosBaalHatanya

      Returns the Baal Hatanya's alos (dawn) calculated as the time when the sun is 16.9° below the eastern geometric horizon before sunrise. For more information the source of 16.9° see ZENITH_16_POINT_9.
      Returns:
      The Date of dawn. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaBaalHatanya

      This method returns the latest zman krias shema (time to recite Shema in the morning). This time is 3 shaos zmaniyos (solar hours) after netz amiti (sunrise) based on the opinion of the Baal Hatanya that the day is calculated from sunrise to sunset. This returns the time 3 * getShaahZmanisBaalHatanya() after netz amiti (sunrise).
      Returns:
      the Date of the latest zman shema according to the Baal Hatanya. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaBaalHatanya

      This method returns the latest zman tfilah (time to recite the morning prayers). This time is 4 hours into the day based on the opinion of the Baal Hatanya that the day is calculated from sunrise to sunset. This returns the time 4 * getShaahZmanisBaalHatanya() after netz amiti (sunrise).
      Returns:
      the Date of the latest zman tfilah. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
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    • getSofZmanAchilasChametzBaalHatanya

      This method returns the latest time one is allowed eating chametz on Erev Pesach according to the opinion of the Baal Hatanya. This time is identical to the Sof zman tfilah Baal Hatanya. This time is 4 hours into the day based on the opinion of the Baal Hatanya that the day is calculated from sunrise to sunset. This returns the time 4 getShaahZmanisBaalHatanya() after netz amiti (sunrise). If it is not erev Pesach, a null will be returned.
      Returns:
      the Date one is allowed eating chametz on Erev Pesach. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
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      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getSofZmanBiurChametzBaalHatanya

      This method returns the latest time for burning chametz on Erev Pesach according to the opinion of the Baal Hatanya. This time is 5 hours into the day based on the opinion of the Baal Hatanya that the day is calculated from sunrise to sunset. This returns the time 5 * getShaahZmanisBaalHatanya() after netz amiti (sunrise). If it is not erev Pesach, a null will be returned.
      Returns:
      the Date of the latest time for burning chametz on Erev Pesach. If it is not erev Pesach or the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      in v 3.0.0 enable the calendar check for erev pesach and return null in all other cases.
    • getMinchaGedolaBaalHatanya

      This method returns the time of mincha gedola. Mincha gedola is the earliest time one can pray mincha. The Rambam is of the opinion that it is better to delay mincha until mincha ketana while the Ra"sh, Tur, GRA and others are of the opinion that mincha can be prayed lechatchila starting at mincha gedola. This is calculated as 6.5 sea level solar hours after netz amiti (sunrise). This calculation is based on the opinion of the Baal Hatanya that the day is calculated from sunrise to sunset. This returns the time 6.5 * getShaahZmanisBaalHatanya() after netz amiti ("real" sunrise).
      Returns:
      the Date of the time of mincha gedola according to the Baal Hatanya. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
      TODO:
      Consider adjusting this to calculate the time as 30 clock or zmaniyos minutes after either astronomical chatzos or chatzos as half a day for calculators that support it, based on ZmanimCalendar.isUseAstronomicalChatzos().
    • getMinchaGedolaBaalHatanyaGreaterThan30

      FIXME synchronous This is a convenience method that returns the later of getMinchaGedolaBaalHatanya() and getMinchaGedola30Minutes(). In the winter when 1/2 of a shaah zmanis is less than 30 minutes getMinchaGedola30Minutes() will be returned, otherwise getMinchaGedolaBaalHatanya() will be returned.
      Returns:
      the Date of the later of getMinchaGedolaBaalHatanya() and getMinchaGedola30Minutes(). If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      TODO:
      Consider adjusting this to calculate the time as 30 clock or zmaniyos minutes after either astronomical chatzos or chatzos as half a day for calculators that support it, based on ZmanimCalendar.isUseAstronomicalChatzos().
    • getMinchaKetanaBaalHatanya

      This method returns the time of mincha ketana. This is the preferred earliest time to pray mincha in the opinion of the Rambam and others. For more information on this see the documentation on mincha gedola. This is calculated as 9.5 sea level solar hours after netz amiti (sunrise). This calculation is calculated based on the opinion of the Baal Hatanya that the day is calculated from sunrise to sunset. This returns the time 9.5 * getShaahZmanisBaalHatanya() after netz amiti (sunrise).
      Returns:
      the Date of the time of mincha ketana. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHaminchaBaalHatanya

      This method returns the time of plag hamincha. This is calculated as 10.75 hours after sunrise. This calculation is based on the opinion of the Baal Hatanya that the day is calculated from sunrise to sunset. This returns the time 10.75 * getShaahZmanisBaalHatanya() after netz amiti (sunrise).
      Returns:
      the Date of the time of plag hamincha. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
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    • getTzaisBaalHatanya

      A method that returns tzais (nightfall) when the sun is 6° below the western geometric horizon (90°) after sunset. For information on the source of this calculation see ZENITH_6_DEGREES.
      Returns:
      The Date of nightfall. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
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    • getFixedLocalChatzosBasedZmanim

      @Deprecated public Date getFixedLocalChatzosBasedZmanim(Date startOfHalfDay, Date endOfHalfDay, double hours)
      Deprecated.
      This method will be replaced in v3.0.0 by the more generic ZmanimCalendar.getHalfDayBasedZman(Date, Date, double) method.
      A utility method to calculate zmanim based on Rav Moshe Feinstein as calculated in MTJ, Yeshiva of Staten Island, and Camp Yeshiva of Staten Island. The day is split in two, from alos / sunrise to fixed local chatzos, and the second half of the day, from fixed local chatzos to sunset / tzais. Morning based times are calculated based on the first 6 hours, and afternoon times based on the second half of the day.
      Parameters:
      startOfHalfDay - The start of the half day. This would be alos or sunrise for morning based times and fixed local chatzos for the second half of the day.
      endOfHalfDay - The end of the half day. This would be fixed local chatzos for morning based times and sunset or tzais for afternoon based times.
      hours - the number of hours to offset the beginning of the first or second half of the day
      Returns:
      the Date of the zman based on calculation of the first or second half of the day. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
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    • getSofZmanShmaMGA18DegreesToFixedLocalChatzos

      This method returns Rav Moshe Feinstein's opinion of the calculation of sof zman krias shema (latest time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) that the day is calculated from dawn to nightfall, but calculated using the first half of the day only. The half a day starts at alos defined as 18° and ends at fixed local chatzos. Sof Zman Shema is 3 shaos zmaniyos (solar hours) after alos or half of this half-day.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA16Point1DegreesToFixedLocalChatzos

      This method returns Rav Moshe Feinstein's opinion of the calculation of sof zman krias shema (latest time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) that the day is calculated from dawn to nightfall, but calculated using the first half of the day only. The half a day starts at alos defined as 16.1° and ends at fixed local chatzos. Sof Zman Shema is 3 shaos zmaniyos (solar hours) after this alos or half of this half-day.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA90MinutesToFixedLocalChatzos

      This method returns Rav Moshe Feinstein's opinion of the calculation of sof zman krias shema (latest time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) that the day is calculated from dawn to nightfall, but calculated using the first half of the day only. The half a day starts at alos defined as 90 minutes before sunrise and ends at fixed local chatzos. Sof Zman Shema is 3 shaos zmaniyos (solar hours) after this alos or half of this half-day.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaMGA72MinutesToFixedLocalChatzos

      This method returns Rav Moshe Feinstein's opinion of the calculation of sof zman krias shema (latest time to recite Shema in the morning) according to the opinion of the Magen Avraham (MGA) that the day is calculated from dawn to nightfall, but calculated using the first half of the day only. The half a day starts at alos defined as 72 minutes before sunrise and ends at fixed local chatzos. Sof Zman Shema is 3 shaos zmaniyos (solar hours) after this alos or half of this half-day.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanShmaGRASunriseToFixedLocalChatzos

      This method returns Rav Moshe Feinstein's opinion of the calculation of sof zman krias shema (latest time to recite Shema in the morning) according to the opinion of the GRA that the day is calculated from sunrise to sunset, but calculated using the first half of the day only. The half a day starts at sunrise and ends at fixed local chatzos. Sof zman Shema is 3 shaos zmaniyos (solar hours) after sunrise or half of this half-day.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSofZmanTfilaGRASunriseToFixedLocalChatzos

      This method returns Rav Moshe Feinstein's opinion of the calculation of sof zman tfila (zman tfilah (the latest time to recite the morning prayers)) according to the opinion of the GRA that the day is calculated from sunrise to sunset, but calculated using the first half of the day only. The half a day starts at sunrise and ends at fixed local chatzos. Sof zman tefila is 4 shaos zmaniyos (solar hours) after sunrise or 2/3 of this half-day.
      Returns:
      the Date of the latest zman krias shema. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaGedolaGRAFixedLocalChatzos30Minutes

      This method returns Rav Moshe Feinstein's opinion of the calculation of mincha gedola, the earliest time one can pray mincha GRAthat is 30 minutes after fixed local chatzos.
      Returns:
      the Date of the time of mincha gedola. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getMinchaKetanaGRAFixedLocalChatzosToSunset

      This method returns Rav Moshe Feinstein's opinion of the calculation of mincha ketana (the preferred time to recite the mincha prayers according to the opinion of the Rambam and others) calculated according to the GRA that is 3.5 shaos zmaniyos (solar hours) after fixed local chatzos.
      Returns:
      the Date of the time of mincha gedola. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getPlagHaminchaGRAFixedLocalChatzosToSunset

      This method returns Rav Moshe Feinstein's opinion of the calculation of plag hamincha. This method returns plag hamincha calculated according to the GRA that the day ends at sunset and is 4.75 shaos zmaniyos (solar hours) after fixed local chatzos.
      Returns:
      the Date of the time of mincha gedola. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
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    • getTzais50

      public Date getTzais50()
      Method to return tzais (dusk) calculated as 50 minutes after sea level sunset. This method returns tzais (nightfall) based on the opinion of Rabbi Moshe Feinstein for the New York area. This time should not be used for latitudes other than ones similar to the latitude of the NY area.
      Returns:
      the Date representing the time. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
    • getSamuchLeMinchaKetanaGRA

      A method for calculating samuch lemincha ketana, / near mincha ketana time that is half an hour before ZmanimCalendar.getMinchaKetana() or is 9 * shaos zmaniyos (solar hours) after sunrise or sea level sunrise (depending on the ZmanimCalendar.isUseElevation() setting), calculated according to the GRA using a day starting at sunrise and ending at sunset. This is the time that eating or other activity can't begin prior to praying mincha. The calculation used is 9 * getShaahZmanis16Point1Degrees() after alos 16.1°. See the Mechaber and Mishna Berurah 232 and 249:2.
      Returns:
      the Date of the time of samuch lemincha ketana. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSamuchLeMinchaKetana16Point1Degrees

      A method for calculating samuch lemincha ketana, / near mincha ketana time that is half an hour before getMinchaGedola16Point1Degrees() or 9 * shaos zmaniyos (temporal hours) after the start of the day, calculated using a day starting and ending 16.1° below the horizon. This is the time that eating or other activity can't begin prior to praying mincha. The calculation used is 9 * getShaahZmanis16Point1Degrees() after alos 16.1°. See the Mechaber and Mishna Berurah 232 and 249:2.
      Returns:
      the Date of the time of samuch lemincha ketana. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also:
    • getSamuchLeMinchaKetana72Minutes

      A method for calculating samuch lemincha ketana, / near mincha ketana time that is half an hour before getMinchaKetana72Minutes() or 9 * shaos zmaniyos (temporal hours) after the start of the day, calculated using a day starting 72 minutes before sunrise and ending 72 minutes after sunset. This is the time that eating or other activity can't begin prior to praying mincha. The calculation used is 9 * getShaahZmanis16Point1Degrees() after alos 16.1°. See the Mechaber and Mishna Berurah 232 and 249:2.
      Returns:
      the Date of the time of samuch lemincha ketana. If the calculation can't be computed such as northern and southern locations even south of the Arctic Circle and north of the Antarctic Circle where the sun may not reach low enough below the horizon for this calculation, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.
      See Also: