Winter Solstice

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The Winter Solstice marks either the shortest day or longest night of the year on planet Earth. In the northern hemisphere, the Solstice tales place between December 21-23 and in the Southern Hemispere the Solstice takes place between June 20-23.

"Happy Winter Solstice" was the greeting James T. Kirk sent Spock in his 2293 Christmas card. (TOS novel: The Fearful Summons)

Winter Solstice article at Wikipedia, the free encyclopedia.