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A year without Hanukkah? It’s a mathematical certainty in the year 3031

Time keeps on slippin’ into the future thanks to imperfections in the Hebrew calendar

A year without Hanukkah may sound like the plot to a less-than-stellar Hallmark Channel movie but it’s also a mathematical certainty that’s just 1,000 years away.

In a TikTok video that’s been viewed more than 2 million times, Randolph College math and computer science professor Marc Ordower laid out the reasons why there will be no Festival of Lights in the year 3031.

The reasons have to do with the fact that no calendar perfectly captures the nuances of the Earth’s orbit around the sun and the Hebrew calendar in particular is “complicated,” Ordower told the Forward.

@marcbreathes #math #calendar #hanukkah #professor #professorsoftiktok #learnontiktok ♬ original sound - Marc Ordower

While the Hebrew calendar’s system of leap years — seven of them in a 19 year cycle — is meant to compensate for discrepancies, it still “slips one day against the seasons in about 215 years,” said Ordower.

“The average length of the Hebrew calendar year is about six minutes and 40 seconds too long. And so every 216 years that accumulates to about one day, over what’s called the mean, tropical year.”

The result is that the Jewish holidays are gradually getting later and later. Add all that up and your distant descendants will one day celebrate Hanukkah on Jan. 1, 3032 — and again in December of that year.

Over a long enough period of time, the Hebrew calendar would slowly shift over the entire course of the Gregorian one — the only reason we haven’t had a year with no Hanukkah yet is because “it’s only been about 1,600 years since the Hebrew calendar was mathematized,” said Ordower.

A year without Hannukah according to Randolph College professor Marc Ordower.
A year without Hannukah? It’s a mathematical certainty in 1,000 years Photo by Marc Ordower

Hanukkah isn’t the only holiday that might require some adjustment. In around 15,000 years, “You’ll have to have your Fourth of July hot dog on matzo.”

Ordower isn’t the first person to note the slipping nature of the Hebrew calendar. Ideas have been batted around for years on the best way to fix it. But he is likely the first to bring this somewhat arcane piece of Jewish trivia to the masses via the popular social media site. It’s not his first brush with viral fame. His videos on funky math problems regularly get hundreds of thousands of views. As for why his take on the precarious nature of Jewish time has gotten so much interest, he has a simple theory: It’s Hanukkah right now and TikTokers find the notion of calendar slippage bizarre, interesting and bizarrely interesting.

“When I was a kid in Hebrew school, I remember at least one of my Hebrew school teachers telling me about how wonderful and marvelous and accurate the Hebrew calendar was,” he said. “And it is a wonderful, marvelous calendar but I think they oversold me on the accuracy. And so a lot of people don’t understand that calendars can slip, and the consequences of that, so it’s interesting to people.”

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