Companion

The zenith of 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 / equilux which calculates to 10.2 below geometric zenith.

The zenith of 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.

The zenith of 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.

The zenith of 13.24 below geometric zenith (90). This calculation is used for calculating Rabbeinu Tam's bain hashmashos according to some opinions. NOTE: See comments on bainHashmashosRT13Point24Degrees for additional details about the degrees.

The zenith of 16.9 below geometric zenith (90). This calculation is used for determining alos (dawn) based on the opinion of the Baal Hatanya. It is based on the calculation that the time between dawn and netz amiti (sunrise) is 72 minutes, the time that is takes to walk 4 mil at 18 minutes a mil (Rambam and others). The sun's position at 72 minutes before netz amiti (sunrise) in Jerusalem around the equinox / equilux is 16.9 below geometric zenith.

The zenith of 19 below geometric zenith (90). This calculation is used for calculating alos according to some opinions.

The zenith of 19.8 below geometric zenith (90). This calculation is used for calculating alos (dawn) and tzais (nightfall) according to some opinions. This calculation is based on the position of the sun 90 minutes after sunset in Jerusalem around the equinox / equilux which calculates to 19.8 below geometric zenith.

The zenith of 1.583 below geometric zenith (90). This calculation is used for calculating netz amiti (sunrise) and shkiah amiti (sunset) based on the opinion of the Baal Hatanya.

The zenith of 26 below geometric zenith (90). This calculation is used for calculating alos (dawn) and tzais (nightfall) according to some opinions. This calculation is based on the position of the sun 120 minutes after sunset in Jerusalem oaround the equinox / equilux which calculates to 26 below geometric zenith. Since the level of darkness when the sun is 26 and at a point when the level of darkness 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 or avoiding eating this early on a fast day.

The zenith of 3.65 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) according to some opinions. This calculation is based on the position of the sun 13.5 minutes after sunset (3/4 of an 18-minute Mil) in Jerusalem around the equinox / equilux which calculates to 3.65 below geometric zenith.

The zenith of 3.676 below geometric zenith (90).

The zenith of 3.7 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) based on the opinion of the Geonim that tzais is the time it takes to walk 3/4 of a Mil at 18 minutes a Mil, or 13.5 minutes after sunset. The sun is 3.7 below geometric zenith at this time in Jerusalem around the equinox / equilux.

The zenith of 3.8 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) based on the opinion of the Geonim that tzais is the time it takes to walk 3/4 of a Mil at 18 minutes a Mil, or 13.5 minutes after sunset. The sun is 3.8 below geometric zenith at this time in Jerusalem around the equinox / equilux.

The zenith of 4.37 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) according to some opinions. This calculation is based on the position of the sun 16 7/8 minutes after sunset (3/4 of a 22.5-minute Mil) in Jerusalem around the equinox / equilux, which calculates to 4.37 below geometric zenith.

The zenith of 4.61 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) according to some opinions. This calculation is based on the position of the sun 18 minutes after sunset (3/4 of a 24-minute Mil) in Jerusalem [around the equinox

The zenith of 4.8 below geometric zenith (90).

The zenith of 5.88 below geometric zenith (90).

The zenith of 5.95 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) according to some opinions. This calculation is based on the position of the sun 24 minutes after sunset in Jerusalem around the equinox / equilux, which calculates to 5.95 below geometric zenith.

The zenith of 6 below geometric zenith (90). This calculation is used for calculating tzais / nightfall based on the opinion of the Baal Hatanya. This calculation is based on the position of the sun 24 minutes after sunset in Jerusalem around the equinox / equilux, which is 6 below geometric zenith.

The zenith of 6.45 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) according to some opinions. This is based on the calculations of Rabbi Yechiel Michel Tucazinsky of the position of the sun no later than 31 minutes after sunset in Jerusalem, and at the height of the summer solstice, this zman is 28 minutes after shkiah. This computes to 6.45 below geometric zenith. This calculation is found in the Birur Halacha Yoreh Deah 262 it the commonly used zman in Israel. It should be noted that this differs from the 6.1/6.2 calculation for Rabbi Tucazinsky's time as calculated by the Hazmanim Bahalacha Vol II chapter 50:7 (page 515).

The zenith of 7.083 below geometric zenith (90). This is often referred to as 75' or 7 and 5 minutes. This calculation is used for calculating alos (dawn) and tzais (nightfall) according to some opinions. This calculation is based on observation of 3 medium sized stars by Dr. Baruch Cohen in his calendar published in in 1899 in Strasbourg, France. This calculates to 7.0833333 below geometric zenith. The [Sh"Ut

The zenith of 7.65 below geometric zenith (90). This calculation is used for calculating misheyakir according to some opinions.

The zenith of 7.67 below geometric zenith (90). This calculation is used for calculating tzais according to some opinions.

The zenith of 9.3 below geometric zenith (90). This calculation is used for calculating tzais (nightfall) according to some opinions.

The zenith of 9.5 below geometric zenith (90). This calculation is used for calculating misheyakir according to some opinions.

The zenith of 9.75 below geometric zenith (90). This calculation is used for calculating alos (dawn) and tzais (nightfall) according to some opinions.

The zenith of 2.1 above geometric zenith (90). This calculation is used for calculating the start of bain hashmashos (twilight) of 13.5 minutes before sunset converted to degrees according to the Yereim. As is traditional with degrees below the horizon, this is calculated without refraction and from the center of the sun. It would be 0.833 less without this.

The zenith of 2.8 above geometric zenith (90). This calculation is used for calculating the start of bain hashmashos (twilight) of 16.875 minutes before sunset converted to degrees according to the Yereim. As is traditional with degrees below the horizon, this is calculated without refraction and from the center of the sun. It would be 0.833 less without this.

The zenith of 3.05 above geometric zenith (90). This calculation is used for calculating the start of bain hashmashos (twilight) of 18 minutes before sunset converted to degrees according to the Yereim. As is traditional with degrees below the horizon, this is calculated without refraction and from the center of the sun. It would be 0.833 less without this.