Rabbis' Voice Articles

Holidays, Late and Early

Is Hanukkah late this year? Is Passover early? When is Purim?

These are questions we all hear every so often, so perhaps it’d be helpful to explain a little something about the Jewish calendar. The solar calendar is about 365 days, whereas the lunar (i.e. Jewish and Muslim) calendar is 354 days. So, every year, the Jewish calendar slips 11 days earlier in relation to the solar calendar. If Passover is on April 11, the next year it’ll be on April 1. The following year, it will be on March 22. And earlier and earlier and earlier.

That’s what actually happens with the Muslim calendar, and why Ramadan is not consistently at the time of year every year.

But we can’t have Pesach in the winter, Hanukkah in the summer, and Yom Kippur in the spring. Passover must be in the spring, so the rabbis figured out a way to fix the calendar. About every two and a half years, there is a leap month that adds a whole 30 days to the year. But the calendar still is slipping back 11 days each year, so in a leap year, the holidays get 19 days later than the previous year.

How do we know what years are leap years? There’s something called the metonic cycle, which was known by the Babylonians, the ancient Greeks, the Chinese, and the ancient Hebrews, among others. The idea is that 19 solar years is the equivalent of 19 lunar years plus 7 extra months. So, 7 of the 19 years are leap years, with an extra month.

We are currently in year 3 of the 19-year cycle, in which years 3, 6, 8, 11, 14, and 17 are leap years. So, this year is a leap year!

We had the leap month as a second month of Adar, the month preceding Passover, so Passover will be “late” this year, beginning on April 20. Then Passover in 2020 will be 11 days earlier, on April 9, then March 28 in 2021, and then 2022 is a leap year again.  Passover will be 19 days later on April 16.

So, there’s a range of dates within which the holidays can fluctuate. We all remember a particularly early Hanukkah combined with Thanksgiving falling late in November, creating Thanksgivukkah a few years ago, for example. But it was noteworthy because it was unusual.

May your Hanukkah be sweet, bright and right on time!