Occurs every year between December 20 and 22.
Usually the exact December Solstice occurs on December 21, except in leap years where it happens on December 22.
The December Solstice is known in the Northern Hemisphere as Winter Solstice, while in the Southern Hemisphere it’s the Summer Solstice.
Because the hemispheres experience the seasons opposite from each other because of the tilt in the earth axis.
For people in the Northern Hemisphere it is hard to picture people celebrating holidays that they know as winter holidays in the summer time.