December solstice

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UT date and time of
equinoxes and solstices on Earth[1]
event equinox solstice equinox solstice
month March June September December
year
day time day time day time day time
2013 20 11:02 21 05:04 22 20:44 21 17:11
2014 20 16:57 21 10:51 23 02:29 21 23:03
2015 20 22:45 21 16:38 23 08:21 22 04:48
2016 20 04:30 20 22:34 22 14:21 21 10:44
2017 20 10:28 21 04:24 22 20:02 21 16:28
2018 20 16:15 21 10:07 23 01:54 21 22:23
2019 20 21:58 21 15:54 23 07:50 22 04:19
2020 20 03:50 20 21:44 22 13:31 21 10:02
2021 20 09:37 21 03:32 22 19:21 21 15:59
2022 20 15:33 21 09:14 23 01:04 21 21:48
2023 20 21:24 21 14:58 23 06:50 22 03:27
Illumination of Earth by the Sun on the day of the December solstice

The December solstice, also known as the southern solstice, is the solstice that occurs each December, typically between the 20th and the 22nd day of the month according to the Gregorian calendar. In the Southern Hemisphere, the December solstice is the summer solstice, whilst in the Northern Hemisphere it is the winter solstice.

Dates[edit]

Recent, past, and future dates and times, in Universal Time, of the December solstice are:[2]

Date time
2000-12-21 13:37
2001-12-21 19:21
2002-12-22 01:14
2003-12-22 07:04
2004-12-21 12:42
2005-12-21 18:35
2006-12-22 00:22
2007-12-22 06:08
2008-12-21 12:04
2009-12-21 17:47
2010-12-21 23:38
2011-12-22 05:30
2012-12-21 11:12
2013-12-21 17:11
2014-12-21 23:03
2015-12-22 04:48
2016-12-21 10:44
2017-12-21 16:28
2018-12-21 22:23
2019-12-22 04:19
2020-12-21 10:02

Solar year[edit]

The December solstice solar year is the solar year based on the December solstice. It is thus the length of time between adjacent December solstices.

The length of the December solstice year has been relatively stable between 6000 BC and 2000 at 49:30 (minutes:seconds) to 50:00 in excess of 365 days and 5 hours. After 2000 it is getting shorter. In 4000 the excess time will be 48:52 and in 10000 46:45.[3]

The length of the day on December solstice[edit]

The following tables contain information on the length of the day on the winter solstice of the Northern Hemisphere and the summer solstice of the Southern Hemisphere (i.e. December solstice). The data was collected from the website of the Finnish Meteorological Institute on 22 December 2015, as well as from certain other websites.[4][5][6][7]

The data is arranged geographically and within the tables from the shortest day to the longest one.

The Nordic countries and the Baltic states
City Sunrise
22 Dec 2015
Sunset
22 Dec 2015
Length of the day
Bodø 11:36 12:25 0 h 49 min
Rovaniemi 11:08 13:22 2 h 14 min
Luleå 9:55 13:04 3 h 09 min
Reykjavík 11:22 15:29 4 h 07 min
Trondheim 10:01 14:31 4 h 30 min
Tórshavn 9:51 14:59 5 h 08 min
Helsinki 9:24 15:13 5 h 49 min
Oslo 9:18 15:12 5 h 54 min
Tallinn 9:17 15:20 6 h 02 min
Stockholm 8:43 14:48 6 h 04 min
Riga 9:00 15:43 6 h 43 min
Copenhagen 8:37 15:38 7 h 01 min
Vilnius 8:40 15:54 7 h 14 min
Europe
City Sunrise
22 Dec 2015
Sunset
22 Dec 2015
Length of the day
Edinburgh 8:42 15:40 6 h 57 min
Moscow 8:57 15:58 7 h 00 min
Berlin 8:15 15:54 7 h 39 min
London 8:04 15:53 7 h 49 min
Kiev 7:56 15:56 8 h 00 min
Paris 8:41 16:56 8 h 14 min
Rome 7:34 16:42 9 h 07 min
Madrid 8:34 17:51 9 h 17 min
Lisbon 7:51 17:18 9 h 27 min
Athens 7:37 17:09 9 h 31 min
Africa
City Sunrise
22 Dec 2015
Sunset
22 Dec 2015
Length of the day
Cairo 6:47 16:59 10 h 12 min
Dakar 7:30 18:46 11 h 15 min
Addis Ababa 6:35 18:11 11 h 36 min
Nairobi 6:25 18:37 12 h 11 min
Kinshasa 5:45 18:08 12 h 22 min
Dar es Salaam 6:05 18:36 12 h 31 min
Luanda 5:46 18:24 12 h 38 min
Antananarivo 5:10 18:26 13 h 16 min
Windhoek 6:04 19:35 13 h 31 min
Johannesburg 5:12 18:59 13 h 47 min
Cape Town 5:32 19:57 14 h 25 min
Americas
City Sunrise
22 Dec 2015
Sunset
22 Dec 2015
Length of the day
Fairbanks 10:58 14:40 3 h 41 min
Anchorage 10:14 15:42 5 h 27 min
Vancouver 8:05 16:16 8 h 11 min
Seattle 7:55 16:20 8 h 25 min
Ottawa 7:39 16:22 8 h 42 min
Toronto 7:48 16:43 8 h 55 min
New York City 7:16 16:32 9 h 15 min
Washington, D.C. 7:23 16:49 9 h 26 min
Los Angeles 6:55 16:48 9 h 53 min
Dallas 7:25 17:25 9 h 59 min
Miami 7:03 17:35 10 h 31 min
Honolulu 7:04 17:55 10 h 50 min
Mexico City 7:06 18:03 10 h 57 min
Managua 6:01 17:26 11 h 24 min
Bogotá 5:59 17:50 11 h 51 min
Quito 6:08 18:16 12 h 08 min
Recife 5:00 17:35 12 h 35 min
Lima 5:41 18:31 12 h 50 min
La Paz 5:57 19:04 13 h 06 min
Rio de Janeiro 6:04 19:37 13 h 33 min
São Paulo 6:17 19:52 13 h 35 min
Porto Alegre 6:20 20:25 14 h 05 min
Santiago 6:29 20:52 14 h 22 min
Buenos Aires 5:37 20:06 14 h 28 min
Ushuaia 4:51 22:11 17 h 19 min
Asia and Oceania
City Sunrise
22 Dec 2015
Sunset
22 Dec 2015
Length of the day
Magadan 8:54 14:55 6 h 00 min
Petropavlovsk 9:36 17:10 7 h 33 min
Khabarovsk 8:48 17:07 8 h 18 min
Ulaanbaatar 8:39 17:02 8 h 22 min
Vladivostok 8:40 17:40 8 h 59 min
Beijing 7:32 16:52 9 h 20 min
Seoul 7:44 17:17 9 h 34 min
Tokyo 6:47 16:31 9 h 44 min
Shanghai 6:48 16:55 10 h 07 min
Lhasa 8:46 19:01 10 h 14 min
Delhi 7:09 17:28 10 h 19 min
Hong Kong 6:58 17:44 10 h 46 min
Manila 6:16 17:32 11 h 15 min
Bangkok 6:36 17:55 11 h 19 min
Singapore 7:01 19:04 12 h 03 min
Jakarta 5:36 18:05 12 h 28 min
Denpasar 5:58 18:36 12 h 37 min
Darwin 6:19 19:10 12 h 51 min
Papeete 5:21 18:32 13 h 10 min
Brisbane 4:49 18:42 13 h 52 min
Perth 5:07 19:22 14 h 14 min
Sydney 5:41 20:05 14 h 24 min
Auckland 5:58 20:39 14 h 41 min
Melbourne 5:54 20:42 14 h 47 min
Invercargill 5:50 21:39 15 h 48 min


Human culture[edit]

Calendars[edit]

The figures in the charts show the differences between the Gregorian calendar and Persian Jalāli calendar in reference to the actual yearly time of the Southern solstice. The error shifts by slightly less than 1/4 day per year; in the Gregorian calendar it is corrected by a leap year every 4th year, omitting three such corrections in every 400 years, so that the average length of a calendar year is 365 97/400 days; while in the Persian calendar every eighth leap-cycle is extended to 5 years, making the average 365 8/33 days, shorter than the Gregorian average by one day every 13200 years.

The date of the solstice is not the same as the date of the latest sunrise and both are not the same as the date of earliest sunset. Because the Earth is moving along its solar orbital path, for each solar day the Earth has to do more than one full rotation. Because the Earth's orbit is elliptical, the speed at which the Earth moves along its orbit varies. Consequently, solar days are not the same length throughout the year. "Mean time" is our way of modifying this, for our convenience, making each day the same length, i.e. 24 hours. The maximum correction (see Equation of Time) is ± 15 minutes to the mean but its value changes quite rapidly around the solstices. If solar time were used rather than mean time, the latest sunrise and earliest sunset and therefore also the shortest day would all be at the December solstice in the northern hemisphere; the opposite would be true in the southern hemisphere, with the earliest sunrise, latest sunset, and longest day.

Commemorations[edit]

References[edit]

  1. ^ United States Naval Observatory (4 January 2018). "Earth's Seasons and Apsides: Equinoxes, Solstices, Perihelion, and Aphelion". Retrieved 18 September 2018. 
  2. ^ Earth's Seasons — Naval Oceanography Portal
  3. ^ Bromberg, Irv. "Solar Year Length Variations on Earth" (PDF). University of Toronto, Canada. Retrieved 21 December 2012. 
  4. ^ "Paikallissää Helsinki" [‘Local weather in Helsinki’] (in Finnish). Finnish Meteorological Institute. 2015-12-22. Retrieved 2015-12-22. 
  5. ^ "Perth, Australia". Retrieved 2015-12-22. 
  6. ^ "São Paulo, Brazil". Retrieved 2015-12-22. 
  7. ^ "Denpasar, Indonesia". Retrieved 2015-12-22.