Rosh Hashanah came earlier this year. Quite early. Which gives us a chance to look at lunar holidays.

Jewish holidays like Rosh Hashanah — also known as the Jewish New Year — are based on lunar cycles and move around on the Gregorian calendar. This year Rosh Hashanah was celebrated from sundown Wednesday to nightfall on Friday.

It marks the beginning of a period of introspection, repentance and hope for redemption that concludes with Yom Kippur, the day of atonement, which goes from the evening of Sept. 13 to the evening of Sept. 14.

Muslim holidays are also based on the moon, but Jewish holidays don’t move around as much as they do. That’s because there’s a corrector in the Jewish calendar that keeps holidays in roughly the same season of year.

This year, holidays are falling early, notes Steve Hunegs, executive director for Jewish Community Relations Council of Minnesota and the Dakotas. That means, for example, the first full day of Hanukkah will start on Thanksgiving Day.

“You have this practically once in an eon confluence between Hanukkah and Thanksgiving,” said Hunegs. “It happened in 1888, but only because in those days Thanksgiving was celebrated on the last Thursday [of November]. Suddenly the great secular American holiday Thanksgiving has — at least from Jewish perspective — a bit of religion added to the mix.”

The next time Jews will see an overlap between Hanukkah and Thanksgiving will be the years 2070 and 2165, Hunegs said.

“It’s an interesting confluence … I’m sure it will be the subject of much comment. My wife is furiously trying to find a turkey menorah, but I said to her, ‘How often can it come into play? Three times in a thousand years or so?’ ” Hunegs quipped.

Hunegs notes the Jewish year is now 5774 and Jewish holidays “fall on the same day each year under the Jewish calendar. … It’s the affixing of the lunar calendar … and the changes that have to be made that casts them on different days within the Gregorian calendar.”