Chanukah and Thanksgiving
Stephen P. Morse, November 10, 2012



Many of you are probably aware that next year, 2013, the first day of Chanukah falls on Thanksgiving day.

I figured it would be interesting to find out when that happened before, and when will it happen again.  The "When-Did" tool in the Calendar section of my website (http://stevemorse.org/jcal/whendid.html) is ideal for getting answers to questions like that.  I decided to find out when the first day of Chanukah fell on Thanksgiving or earlier.  So I went to the "When-Did" tool and entered:
WHEN DID THANKSGIVING COME BETWEEN KISLEV 25 AND ELUL 29
Of course Kislev 25 is the first day of Chanukah, and Elul 29 is the end of the Hebrew year.  I left the default year range of 1900 to 2099.  The only result I got was November 28, 2013.  I extended the year range forward, all the way up to 9999.  Still got only that one result.  I then extended the year range backwards to 1800.  I got several results in the 1800s, the last one being in 1899.  So it did occur in the past, but less and less often as time went on.  The last time it occurred was 113 years ago, long before any of us alive today were born.  And after next year it will never happen again. So as part of our Thanksgiving dinner next year we should all be prepared to light two candles, since the second day of Chanukah will be starting that evening.

Another interesting question to ask is whether we will ever again light Chanukah candles at our Thanksgiving dinner.  As already mentioned, Thanksgiving will never again fall on or after the first day of Chanukah, so we will never again light two or more candles. But will Thanksgiving ever fall on the day before the first day of Chanukah, in which case we will light one candle during our Thanksgiving dinner.  Again, using the "When-Did" tool, I learned that the one-candle Thanksgiving will happen in the year 2070 and then again in 2165.  But after that it will never happen again for all eternity.  So after 2165 we will never again light Chanukah candles on Thanksgiving day.

Here's a summary of when you light Chanukah candles during the Thanksgiving dinner.  If Thanksgiving falls on Kislev 24 (day before first day of Chanukah), you light one candle. If it falls on Kislev 25, you light two candles.  And so forth.  So using my "When-Did" tool I was able to determine how many candles to light on Thanksgiving, for all years from 1600 to the end of time (before 1600 there was no Thanksgiving).
Light one candle on Thanksgiving: 1600, 1671, 1698, 1725, 1793, 1820, 1823, 1918, 2070, 2165
Light two candles on Thanksgiving: 1614, 1641, 1668, 1709, 1736, 1766, 1861, 1888, 2013
Light three candles on Thanksgiving: 1679 , 1804
Light four candles on Thanksgiving: never
Light five candles on Thanksgiving: 1652, 1690, 1747, 1899
Light six, seven, or eight candles on Thanksgiving: never
What I wrote above is not completely true.  I tested it up to the year 9999, which is the furthest that my “When-Did” tool lets you go. The reason Chanukah-before-Thanksgiving occurred in the past, and with decreasing frequency as time went on, is because there is a slow drift between the Hebrew Calendar and the secular (Gregorian) calendar.  That drift amounts to one day every 217 years.  So in about 80,000 years it will drift by one full year and we'll be back to where we started.  At that time we will once again be lighting Chanukah candles at our Thanksgiving dinner.

By using a modified version of my “When-Did” tool (one that goes up to year 99,999 instead of 9,999), I was able to determine the next time after 2165 that we again light candles on Thanksgiving. Specifically I searched for the next times that Thanksgiving falls between Kislev 24 (day before first day of Chanukah) and Tevet 2 (next-to-last possible day of Chanukah). Here are the first two results:
November 22, 76942 = Tevet 2, 80702
November 22, 77094 = Kislev 30, 80854
So in the year 76,942, Thanksgiving will fall on Tevet 2. But Tevet 2 is problematic because sometimes Tevet 2 is the last day of Chanukah instead of the next-to-last day (depends on whether Kislev has 30 days in that year or has only 29 days).  And from my modified “When-Did” tool, I learned that Kislev will indeed have 30 days that year, so Tevet 2 will be the last day of Chanukah and we won't light any candles on that Thanksgiving.

In the year 77,094, Thanksgiving will fall on Kislev 30, which is always the 6th day of Chanukah (regardless of the number of days in Kislev).  So the 7th day will be starting during the Thanksgiving feast, and we will light seven candles. This is the first time after 2165 that we will again be lighting candles on Thanksgiving.

And the next time after 2013 that Thanksgiving falls on the first day of Chanukah will be in the year 79,043.

Postscript: Turns out I'm not the only person writing about the coincidence of Chanukah and Thanksgiving. Two others whom I've stumbled across are Eli Lansey and Jonathan Mizrahi. Our dates don't always agree, and where they differ mine of course are the correct ones.

© Stephen P. Morse, 2012