Tsukimi or Otsukimi (moon-viewing) is known an annual Japanese festival in appreciation of the autumn moon.
It falls on the night of August 15 (of the lunar calendar), as the full moon in the clear autumn sky is quite beautiful.
These days normally fall in September and October of the modern solar calendar.
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Tsukimi refers to the Japanese tradition of holding parties to view the harvest moon.
The custom is thought to have originated with Japanese aristocrats during the Heian period (from A.D.794 ~ 1192).

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Tsukimi traditions include displaying decorations made from Susuki (Japanese pampas grass) and eating Tsukimi Dango (rice dumplings) in order to celebrate the beauty of the moon.
When the Japanese see the full moon, they see an image of a rabbit making rice cakes (mochi).