Harvest Moon in September or October?
The Harvest Moon varies between September or October in the Northern Hemisphere. It is the Full Moon nearest the autumnal (fall) equinox.
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September: Harvest or Corn Moon
The September Full Moon is usually the Harvest Moon, but this depends on the equinox. It is also called Full Corn Moon or Barley Moon.
First day of Sukkot
Sukkot is a Jewish holiday lasting 7 days. It begins on the 15th of Tishrei, which falls into September or October.
Hoshana Rabbah
Jewish people in the UK celebrate Hoshana Rabbah, also spelled Hoshana Raba, on the last day of the Sukkot festival.