The shortest day and longest night of 2023 fall on Thursday, December 21, coinciding with the winter solstice which will occur at 9:27 p.m. local time.
If the earth’s axis were perpendicular to the plane of its orbit around the sun, every day of the year would be equal in length and the planet would know no seasons. As it happens, the earth’s axis is at an angle, generating four celestial events that mark the start of spring, summer, fall and winter.
Dates when the sun’s apparent path crosses the equator roll around twice a year: at the vernal equinox in March and the autumnal equinox in September.
The solstices occur when the sun reaches either of the two points on the elliptic most distant from the equator. In this position the sun gives the appearance of “standing still” as it rises to approximately the same noontime elevation for several days running.
Rituals and ceremonies involving fire and candles to represent the waxing and waning of the sun have been observed by diverse civilizations since ancient times. The Roman celebration of the Natalis Solis Invicti and Yuletide rituals originated by the Vikings were associated with the winter solstice and eventually gave rise to Christian Christmas festivities of more recent times.
Daylight hours on December 21, the northern hemisphere’s shortest day (sunrise to sunset)
- Bogota: 11:51:33 (5:58 a.m. to 5:50 p.m.)
- Guadalajara: 10:52:48 (7:25 a.m. to 6:17 p.m.)
- Miami: 10:31:48 (7:02 a.m. to 5:34 p.m.)
- New York: 9:15:17 (7:16 a.m. to 4:32 p.m.)
- Toronto: 8:55:45 (7:47 a.m. to 4:43 p.m.)
- London: 7:49:42 (8:03 a.m. to 3:53 p.m.)
- Edinburgh: 6:57:38 (8:41 a.m. to 3:39 p.m.)
- Stockholm: 6:04:49 (8:43 a.m. to 2:48 p.m.)
- Reykjavik: 4:07:10 (11:22 a.m. to 3:29 p.m.)
Spare a thought for residents of Tromso, Norway, when for various weeks at this time the sun does not rise at all. There is a subtle twilight light from about 9 a.m. to 2 p.m., but otherwise the city is dark. While this may sound a bit gloomy, Tromso locals report lower levels of wintertime depression than expected.
Encouragingly from December 21 onward, the days become increasingly longer, leading up to the Summer Solstice, or the June Solstice, and the longest day of the year.