Winter solstice

People watch fireworks at the end of the Burning the Clocks Festival in Brighton, England. The annual celebration is enjoyed by thousands of people who carry paper lanterns through the streets, culminating on Brighton Beach, where the lanterns are burned and the winter solstice is marked. (Dan Kitwood / Getty Images)

March 21, 2014 10:52 AM PT

A solstice occurs twice a year, when the sun’s position in the sky, as viewed from Earth, reaches its farthest points north and south from the celestial equator. The winter solstice marks the shortest day of the year; the summer solstice marks the longest.

One of the illuminated lanterns at the Burning the Clocks Festival in Brighton, England. (Dan Kitwood / Getty Images)

A giant lantern burns at the end of the Burning the Clocks Festival. (Dan Kitwood / Getty Images)

People carry lanterns at the Burning the Clocks Festival. (Dan Kitwood / Getty Images)

Dancers make their way throught the streets during the Burning the Clocks Festival. (Dan Kitwood / Getty Images)

More revelers make their way throught the streets at Burning the Clocks Festival. (Dan Kitwood / Getty Images)

People watch starlings come home to roost on Brighton’s Old Pier as the sun sets. (Dan Kitwood / Getty Images)