Winter solstice 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 observing the sunrise and sunset or using an astronomically aligned instrument that allows a ray of light to be cast on a certain point around that time. Length of day
December month"). The French Republican Calendar contained December within the months of Frimaire and Nivôse. December contains the winter solstice in the Northern Hemisphere, the day with the fewest daylight hours, and the summer solstice in the Southern Hemisphere, the day with the most daylight hours (excluding polar regions in both cases). December in the Northern Hemisphere is the seasonal equivalent to June in the Southern Hemisphere and vice versa. In the Northern hemisphere, the beginning of the astronomical winter is traditionally 21 December or the date of the solstice. Meteor showers occurring in December are the Andromedids (September 25 –