Summer solstice

It has been suggested that Xiazhi be merged into this article. (Discuss) Proposed since January 2022.

Earth during the summer solstice in June 2017

The summer solstice, also known as estival solstice^[3] or midsummer, occurs when one of Earth's poles has its maximum tilt toward the Sun. It happens twice yearly, once in each hemisphere (Northern and Southern). For that hemisphere, the summer solstice is when the Sun reaches its highest position in the sky (for areas outside of the tropics) and is the day with the longest period of daylight. Within the Arctic circle (for the northern hemisphere) or Antarctic circle (for the southern hemisphere), there is continuous daylight around the summer solstice. On the summer solstice, Earth's maximum axial tilt toward the Sun is 23.44°.^[4] Likewise, the Sun's declination from the celestial equator is 23.44°.

The summer solstice occurs during summer.^[5] This is the June solstice in the Northern Hemisphere and the December solstice in the Southern Hemisphere. Depending on the shift of the calendar, the summer solstice occurs sometime between June 20 and June 22 in the Northern Hemisphere^[6][7] and between December 20 and December 23 in the Southern Hemisphere.^[8] The same dates in the opposite hemisphere are referred to as the winter solstice.

Since prehistory, the summer solstice has been seen as a significant time of year in many cultures, and has been marked by festivals and rituals. Traditionally, in many temperate regions (especially Europe), the summer solstice is seen as the middle of summer and referred to as "midsummer". Today, however, in some countries and calendars it is seen as the beginning of summer.

Distinctions[]

Diagram of Earth's seasons as seen from the north. Far left: summer solstice for the Northern Hemisphere. Front right: summer solstice for the Southern Hemisphere.

Although the summer solstice is the longest day of the year for that hemisphere, the dates of earliest sunrise and latest sunset vary by a few days.^[9] This is because Earth orbits the Sun in an ellipse, and its orbital speed varies slightly during the year.^[4]

Although the Sun appears at its highest altitude from the viewpoint of an observer in outer space or a terrestrial observer outside tropical latitudes, the highest altitude occurs on a different day for certain locations in the tropics, specifically those where the Sun is directly overhead (maximum 90 degrees elevation) at the subsolar point. This day occurs twice each year for all locations between the Tropic of Cancer and Tropic of Capricorn because the overhead Sun appears to cross a given latitude once before the day of the solstice and once afterward. For example, Lahaina Noon occurs in May and July in Hawaii. See solstice article. For all observers, the apparent position of the noon Sun is at its most northerly point on the June solstice and most southerly on the December solstice.

Full moon[]

The year 2016 was the first time in nearly 70 years that a full moon and the Northern Hemisphere's summer solstice occurred on the same day.^[10] The 2016 summer solstice's full moon rose just as the Sun set.^[11]

Cultural aspects[]

The significance given to the summer solstice has varied among cultures, but most recognize the event in some way with holidays, festivals, and rituals around that time with themes of religion or fertility.^[12] For example, in Sweden, midsummer is one of the year's major holidays when the country closes down as much as during Christmas. In some regions, the summer solstice is seen as the beginning of summer and the end of spring. In other cultural conventions, the solstice is closer to the middle of summer.^[13]

Summer solstice sunset over the Mojave Desert 7:54 p.m. PDT (19:54) June 20, 2016

Longreach, Queensland at mid-day of Summer Solstice (with respect to southern hemisphere) or Winter Solstice (with respect to Northern hemisphere), 22 December 2019. The town is on the Tropic of Capricorn (Shadow directly below the sign)

Solstice is derived from the Latin words sol (Sun) and sistere (to stand still).

Date[]

Celebrations[]

• Midsummer
• Noc Kupały (Poland)
• Dragon Boat Festival (East Asia)
• Christmas typically marks the southern summer solstice.
• Saint John's Eve or June solstice celebration (Catalan countries)
• Day of Private Reflection (Northern Ireland)
• Jaanipäev (Estonia)
• Juhannus (Finland)
• Jāņi (Latvia)
• Rasos (Lithuania)
• National Aboriginal Day (Canada)
• Tiregān (Iran)
• Fremont Solstice Parade (Fremont, Seattle, Washington, United States)
• Santa Barbara Summer Solstice Parade (Santa Barbara, California, United States)
• International Surfing Day
• International Yoga Day
• Fête de la Musique, also known as World Music Day

Winter solstice in the Southern Hemisphere[]

• Inti Raymi, Machu Picchu, Peru
• We Tripantu, (Mapuche, southern Chile)
• Willkakuti, an Andean-Amazonic New Year (Aymara)

Length of the day on the summer solstice of the north[]

The following tables contain information on the length of the day on the 20th June, close to the summer solstice of the Northern Hemisphere and winter solstice of the Southern Hemisphere (i.e. June solstice). The data was collected from the website of the Finnish Meteorological Institute on 20 June 2016^[14] as well as from certain other websites.^{[15][16][17][18][19][20][21][22][23][24][25]}

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

Fennoscandia and the Baltic states
City	Sunrise 20 June 2016	Sunset 20 June 2016	Length of the day
Murmansk	—	—	24 h
Bodø	—	—	24 h
Rovaniemi	—	—	24 h
Luleå	1:00	21.6.2016 0:05	23 h 04 min
Kem’	1:44	23:42	21 h 58 min
Reykjavík	2:55	21.6.2016 0:03	21 h 08 min
Trondheim	3:02	23:37	20 h 35 min
Tórshavn	3:36	23:21	19 h 45 min
Petrozavodsk	2:55	22:33	19 h 38 min
Helsinki	3:54	22:49	18 h 55 min
Saint Petersburg	3:35	22:25	18 h 50 min
Oslo	3:53	22:43	18 h 49 min
Tallinn	4:03	22:42	18 h 39 min
Stockholm	3:30	22:07	18 h 37 min
Riga	4:29	22:21	17 h 52 min
Copenhagen	4:25	21:57	17 h 32 min
Vilnius	4:41	21:59	17 h 17 min

Europe
City	Sunrise 20 June 2016	Sunset 20 June 2016	Length of the day
Edinburgh	4:26	22:02	17 h 36 min
Moscow	3:44	21:17	17 h 33 min
Berlin	4:43	21:33	16 h 49 min
Warsaw	4:14	21:00	16 h 46 min
London	4:43	21:21	16 h 38 min
Kyiv	4:46	21:12	16 h 26 min
Paris	5:46	21:57	16 h 10 min
Vienna	4:53	20:58	16 h 04 min
Budapest	4:46	20:44	15 h 58 min
Zürich	5:29	21:25	15 h 56 min
Rome	5:34	20:48	15 h 13 min
Madrid	6:44	21:48	15 h 03 min
Lisbon	6:11	21:04	14 h 52 min
Athens	6:02	20:50	14 h 48 min

Africa
City	Sunrise 20 June 2016	Sunset 20 June 2016	Length of the day
Cairo	4:54	18:59	14 h 04 min
Tenerife	7:08	21:05	13 h 57 min
Dakar	6:41	19:41	12 h 59 min
Addis Ababa	6:07	18:46	12 h 38 min
Nairobi	6:32	18:35	12 h 02 min
Kinshasa	6:04	17:56	11 h 52 min
Dar es Salaam	6:32	18:16	11 h 43 min
Luanda	6:20	17:56	11 h 36 min
Jamestown	6:49	17:59	11 h 10 min
Antananarivo	6:21	17:21	10 h 59 min
Windhoek	6:30	17:15	10 h 44 min
Johannesburg	6:54	17:24	10 h 29 min
Cape Town	7:51	17:44	9 h 53 min

Middle East
City	Sunrise 20 June 2016	Sunset 20 June 2016	Length of the day
Tehran	5:48	20:23	14 h 34 min
Beirut	5:27	19:52	14 h 24 min
Baghdad	4:53	19:14	14 h 21 min
Jerusalem	5:33	19:47	14 h 13 min
Manama	4:45	18:32	13 h 46 min
Doha	4:44	18:26	13 h 42 min
Dubai	5:29	19:11	13 h 42 min
Riyadh	5:04	18:44	13 h 39 min
Muscat	5:19	18:55	13 h 35 min
Sana'a	5:33	18:35	13 h 02 min

Americas
City	Sunrise 20 June 2016	Sunset 20 June 2016	Length of the day
Inuvik	—	—	24 h
Fairbanks	2:57	21.6. 00:47	21 h 49 min
Nuuk	2:53	21.6. 00:03	21 h 09 min
Iqaluit	2:11	23:00	20 h 49 min
Anchorage	4:20	23:41	19 h 21 min
Kodiak	5:07	23:14	18 h 06 min
Sitka	4:06	22:00	17 h 54 min
Unalaska	6:34	23:41	17 h 06 min
Edmonton	5:04	22:07	17 h 02 min
Winnipeg	5:19	21:40	16 h 21 min
Vancouver	5:06	21:21	16 h 14 min
Seattle	5:11	21:10	15 h 59 min
Ottawa	5:14	20:54	15 h 40 min
Toronto	5:35	21:02	15 h 26 min
New York	5:24	20:30	15 h 05 min
Washington, D.C.	5:42	20:36	14 h 53 min
Los Angeles	5:42	20:07	14 h 25 min
Miami	6:30	20:14	13 h 44 min
Havana	6:44	20:17	13 h 33 min
Honolulu	5:50	19:16	13 h 25 min
Mexico City	6:59	20:17	13 h 18 min
Managua	5:21	18:11	12 h 50 min
Bogotá	5:46	18:09	12 h 23 min
Quito	6:12	18:19	12 h 06 min
Lima	6:27	17:52	11 h 24 min
La Paz	6:59	18:08	11 h 08 min
Rio de Janeiro	6:32	17:16	10 h 43 min
São Paulo	6:47	17:28	10 h 40 min
Porto Alegre	7:20	17:32	10 h 12 min
Santiago	7:46	17:42	9 h 56 min
Buenos Aires	8:00	17:50	9 h 49 min
Ushuaia	9:58	17:11	7 h 12 min

Asia and Oceania
City	Sunrise 20 June 2016	Sunset 20 June 2016	Length of the day
Provideniya	0:52	22:16	21 h 23 min
Magadan	3:37	22:19	18 h 41 min
Petropavlovsk	4:58	21:55	16 h 56 min
Khabarovsk	4:57	21:04	16 h 07 min
Ulaanbaatar	5:52	21:54	16 h 01 min
Vladivostok	5:32	20:55	15 h 22 min
Beijing	4:45	19:46	15 h 00 min
Seoul	5:11	19:56	14 h 46 min
Tokyo	4:25	19:00	14 h 34 min
Shanghai	4:50	19:01	14 h 10 min
Lhasa	6:55	20:58	14 h 03 min
Delhi	5:23	19:21	13 h 58 min
Kathmandu	5:08	19:02	13 h 53 min
Taipei	5:04	18:46	13 h 41 min
Hong Kong	5:39	19:09	13 h 30 min
Manila	5:27	18:27	12 h 59 min
Bangkok	5:51	18:47	12 h 56 min
Singapore	7:00	19:12	12 h 11 min
Jakarta	6:01	17:47	11 h 45 min
Darwin	7:06	18:29	11 h 23 min
Papeete	6:27	17:32	11 h 04 min
Sydney	6:59	16:53	9 h 53 min
Auckland	7:33	17:11	9 h 37 min
Melbourne	7:35	17:07	9 h 32 min
Dunedin	8:19	16:59	8 h 39 min

Length of day increases from the equator towards the North Pole in the Northern Hemisphere in June (around the summer solstice there), but decreases towards the South Pole in the Southern Hemisphere at the time of the southern winter solstice.

See also[]

• Daytime
• Stonehenge
• Tekufah
• Xiazhi (Summer solstice in Chinese culture)

References[]

External links[]

• Table of dates/times from 1600–2400