Hebrew calendar 2027

The sky in the Hebrew year, 2027

The Hebrew calendar is lunisolar: months follow the Moon, years follow the Sun and days start at sunset. That makes every holiday in 2027 a sky event as well as a date. Here is what the Moon and Sun are doing at each one.

Rosh Hashanah at the new moon

Rosh Hashanah 5788 falls on 1 Tishrei, the only major holiday at the start of a month, when the Moon is new and invisible. The astronomical new moon is on Wed, Sep 29, 10:36 PM, and the holiday begins at sunset on Friday, October 1, 2027. Psalm 81 says "blow the shofar at the new moon, at the full moon for our feast day", which the rabbis read as Rosh Hashanah and Sukkot: the month opens hidden and two weeks later is full. Yom Kippur follows on 10 Tishrei, with a waxing gibbous Moon in the sky as it ends.

Sukkot and Passover at the full moons of the equinoxes

Both pilgrim festivals that last a week begin on the 15th of a month, at full moon, and both are tied to an equinox. Passover, 15 Nisan, follows the March equinox, which in 2027 is on Sat, Mar 20, 4:24 PM; the full moon is on Tue, Apr 20, 6:27 PM and the first Seder on the evening of Wednesday, April 21, 2027. Sukkot, 15 Tishrei, follows the September equinox (Thu, Sep 23, 2:01 AM), with its full moon on Fri, Oct 15, 9:47 AM. A sukkah roof is meant to be thin enough to see the stars through, and at Sukkot the Moon is the brightest of them.

Chanukah in the darkest nights

Chanukah begins on 25 Kislev, near the end of the month, so the Moon is a thin waning crescent or gone. The new moon falls on Mon, Dec 27, 3:12 PM, during the festival, and the December solstice, the longest night of the year in the Northern Hemisphere, is on Tue, Dec 21, 9:42 PM. The candles are lit in the darkest stretch of the year, when neither Moon nor Sun gives much light.

Tu BiShvat and Purim at the full moon

Tu BiShvat (15 Shevat, Sat, Jan 23) and Purim (14 Adar II, Tue, Mar 23) fall within a day or so of the full moon, and so does Shushan Purim in Jerusalem. Tisha B'Av on 9 Av (Thu, Aug 12) comes with a waxing gibbous Moon, a few days before the full moon of Tu B'Av.

Eclipses of the Moon in 2027

A penumbral lunar eclipse on February 20 (UTC) falls on 13 Adar I 5787, the eve of Purim Katan. A penumbral lunar eclipse on July 18 (UTC) falls on 13 Tammuz 5787. A penumbral lunar eclipse on August 17 (UTC) falls on 14 Av 5787. A lunar eclipse can only happen at full moon, so in a lunar calendar it always lands in the middle of a month, on or near the 14th or 15th. Whether you can see it depends on whether the Moon is up where you are.

Molad and the true new moon

The traditional molad uses an average month of 29 days, 12 hours and 793 chalakim, counted from Molad BaHaRaD. The real Moon runs fast or slow around its elliptical orbit, so in 2027 the true new moon came as much as 15.3 hours before the molad (for Cheshvan 5788). The fixed calendar does not need the two to agree: it was designed in the fourth century so that every community could keep the same dates without waiting for witnesses to see the new crescent.

Leap years and the 19-year cycle

5787 is year 11 and 5788 is year 12 of the 19-year cycle, in which years 3, 6, 8, 11, 14, 17 and 19 get a 13th month, Adar I. 5787 is a leap year, which is why Passover 2027 is late. Without the extra month the holidays would slip about 11 days earlier every year. See the full cycle diagram on the Hebrew calendar page.

Every day starts at sunset

All the dates on this page are the daytime part of the Hebrew day. Every holiday, every Rosh Chodesh and every Shabbat begins at sunset the evening before, and the Hebrew date in the grids below changes at sunset too. For today's Hebrew date with your local sunset, the converter and the Hebrew birthday calculator, go to the Hebrew date today page.