Sun Wheel

Also known at the Wheel of Taranis, this symbol represents the solar calendar, with points that mark the position of the sun at equinoxes and solstices.
In Celtic mythology Taranis was the god of thunder worshipped in Gaul and Britain.
this symbol represents the Wheel of the Year and the eight Wiccan sabbats. The term "sun wheel" comes from the solar cross, which was a calendar used to mark the solstices and equinoxes in some pre-Christian European cultures.
Some Celtic sun wheels have twelve spokes representative of the twelve months of the year. Twelve-month based sun wheel expands upon the original Celtic wheel symbol that had six spokes.