Have you heard about Thanksgivukkah?
This coming week, Jews will begin the celebration of Hanukkah, the eight-day festival commemorating the rededication of the ancient Temple in Jerusalem after a program of Greek oppression. At the same time, our civic calendar ushers in the holiday of Thanksgiving, when Americans of all backgrounds and faiths celebrate gratitude.
It is an event that never happened before, and will never happen again.
This might be confusing to those who associate Hanukkah with more of a winter holiday — and thus the conflation with Christmas, which leads to the “holiday season.” But this year, because of some calendric anomalies, Hanukkah falls at the end of November.
To understand why, you need to know that the Jewish calendar is primarily a lunar calendar. We mark the passage of time, and the cycle of the months, by the phases of the moon. This practice is based in our Torah. At the same time, we are not wholly separate from the solar calendar since we are also told in the Torah that certain festivals must fall during a certain season (like Passover in the spring). So really, the Jewish calendar is a lunisolar calendar.
But there is a problem. The average lunar month (using the phases of the moon as a reference — also called a synodic month) is 29.5 days long. This translates into a lunar year of about 354 days. The solar year (the amount of time it takes for the earth to revolve around the sun) is 365 days. That means there is an 11-day difference between the lunar and solar year.
Therefore, without a correction, the Jewish calendar will shift a month in relation to the solar calendar every 2.5 years. This will mean that the holidays will get out of sync with the seasons. Because of the difference in the lunar and solar years, the Jewish holidays in relation to the Gregorian calendar do move around somewhat (which is why on a Gregorian calendar the Jewish holidays fall on different days each year), but a correction is needed to keep them in the same season.
For the Jewish calendar, this means seven times every 19 years is a leap year. And for the Jewish calendar, that means adding a whole extra month! And why 19 years? An ancient Greek astronomer named Meton of Athens noticed that 19 solar years is approximately the same as 235 lunar months (about 6,900 days). Jewish astronomers use the Metonic cycle — as these 19 years are called — as a basis for balancing out the two calendars.
This year is the “earliest” the holidays will ever fall in the Metonic cycle, and so this is the earliest Hanukkah will ever be. And by coincidence, since the first of the November was on a Friday, this is the latest Thanksgiving will ever fall. An early Hanukkah plus late Thanksgiving equals Thanksgivukkah.
One would think that since the Gregorian calendar cycles every seven years and the Jewish calendar every 19 that this should have happened 133 years ago. And while the dates did overlap in 1861, Thanksgiving was not declared a national holiday until 1863! And because of a slight difference in the mean Jewish year and the mean Gregorian year, the Jewish calendar will “slip” one day every 231 years. So it won’t happen again.
There are many creative ways being proposed to mark this rare confluence of events. On the one hand, there is the “mash-up” of food traditions – combining traditional Hanukkah and Thanksgiving fare — like pumpkin latkes or cranberry-stuffed doughnuts. But on another, there is the opportunity to reflect on the spiritual overlap of the two celebrations.
When Abraham Lincoln declared the national holiday, he did so to provide a beacon of hope and light during a dark time in our nation’s history. As Jews light the menorah, we too remember the light that comes from darkness, the ability to rebuild and rededicate. Just as our ancestors rededicated themselves to their traditions after a period of oppression, so too do we dedicate ourselves to our traditions, and we recognize the freedom afforded us by this country to do so. And for that, we are grateful.Rabbi Seth Goldstein has been the spiritual leader of Temple Beth Hatfiloh since 2003.