Winter Solstice - Observances

Observances

Direct observation of the solstice by amateurs is difficult because the sun moves too slowly at either solstice to determine its specific day, let alone its instant. Knowledge of when the event occurs has only recently been facilitated to near its instant according to precise astronomical data tracking. It is not possible to detect the actual instant of the solstice (by definition, one can not observe that an object has stopped moving until one makes a second observation in time showing that it has not moved further from the preceding spot, or that it has moved in the opposite direction). Further, to be precise to a single day one must be able to observe a change in azimuth or elevation less than or equal to about 1/60 of the angular diameter of the sun. Observing that it occurred within a two-day period is easier, requiring an observation precision of only about 1/16 of the angular diameter of the sun. Thus, many observations are of the day of the solstice rather than the instant. This is often done by watching the sunrise and sunset or vice versa or using an astronomically aligned instrument that allows a ray of light to cast on a certain point around that time.

Before the scientific revolution many forms of observances, astronomical, symbolic or ritualistic, had evolved according to the beliefs of various cultures, many of which are still practiced today. The following is an alphabetical list of observances believed to be directly linked to the winter solstice.