A birthday on the globe
21 December on the globe: what happened in the world on this day, and who was born
For 21 December, the English Wikipedia lists 44 events and 178 births. 30 of the events stand at their places as rays of light. The taller the ray, the longer ago it happened. The people born that day come further down, as blue points.
A birthday, yours or someone else’s:
Turn it into a greetingScroll: the globe turns to each place
The day you were born, on the globe.
Three things from your day
Scroll: your day first, then 21 December through the years
The Earth on 21 December
The picture on the globe was assembled by NASA from satellite photographs taken in December 2004: the snow, the ice and the green are those of the month.
On 21 December the Sun passes straight overhead at noon along the parallel of 23.4° south. In London, the day lasts about 7 hours 50 minutes.
Beyond 67° south the Sun no longer sets; beyond 67° north it no longer rises.
The line between day and night is tilted on the globe exactly as on this day of the year. On the dark side you can see the lights of towns.
Britain & Ireland · Rochdale
1844
The Rochdale Society of Equitable Pioneers commences business at its cooperative in Rochdale, England, starting the Cooperative movement.
On the map: Rochdale.
Also on the day’s list of Wikipedia in Romanian.
Britain & Ireland · Portsmouth
1872
Challenger expedition: HMS Challenger, commanded by Captain George Nares, sails from Portsmouth, England.
On the map: Portsmouth.
Also on the day’s list of Wikipedia in Chinese.
Britain & Ireland · Lancaster House
1979
Lancaster House Agreement: An independence agreement for Rhodesia is signed in London by Lord Carrington, Sir Ian Gilmour, Robert Mugabe, Joshua Nkomo, Bishop Abel Muzorewa and S.C. Mundawarara.
On the map: Lancaster House.
Britain & Ireland · Thames Estuary
2018
Operatives of the British Special Boat Service boarded the container ship Grande Tema in the Thames Estuary to detain four stowaways who had threatened the crew.
On the map: Thames Estuary.
Europe · Cathedral of the Immaculate Conception
1911
Moscow's Cathedral of the Immaculate Conception was consecrated.
On the map: Cathedral of the Immaculate Conception.
Asia · Singha Durbar
1923
United Kingdom and Nepal formally sign an agreement of friendship, called the Nepal–Britain Treaty of 1923, which superseded the Treaty of Sugauli signed in 1816.
On the map: Singha Durbar.
Also on the day’s list of Wikipedia in Romanian.
Asia · Bethlehem
1995
The city of Bethlehem passes from Israeli to Palestinian control.
On the map: Bethlehem.
Also on the day’s list of Wikipedia in Romanian and Chinese.
Latin America · Popocatépetl
1994
Mexico's Popocatépetl volcano, dormant for 47 years, began erupting, and is now one of the nation's most active volcanoes.
On the map: Popocatépetl.
Also on the day’s list of Wikipedia in Spanish.
North America · Plymouth Rock
1620
Plymouth Colony: William Bradford and the Mayflower Pilgrims land near what is now known as Plymouth Rock in Plymouth, Massachusetts.
On the map: Plymouth Rock.
Also on the day’s list of Wikipedia in Romanian and Chinese.
North America · Carthay Circle Theatre
1937
Snow White and the Seven Dwarfs, the first full-length cel-animated feature in film history, premiered at the Carthay Circle Theatre in Los Angeles.
On the map: Carthay Circle Theatre.
North America · Kennedy Space Center
1968
Apollo program: Apollo 8 is launched from the Kennedy Space Center, placing its crew on a lunar trajectory for the first visit to another celestial body by humans.
On the map: Kennedy Space Center.
21 December
What the other Wikipedias remember#
For these years the English list has nothing on this day. The events below come from the same day’s lists on Wikipedia in Chinese and Romanian and were translated for this page.
From Wikipedia in Chinese · Rondane National Park
1962
Rondane National Park, Norway's first national park, is officially established.
On the map: Rondane National Park.
Translated from the list on Wikipedia in Chinese.
From Wikipedia in Romanian · Bucharest
1989
The Romanian Revolution. In Bucharest, Nicolae Ceaușescu holds a rally in what is now "Revolution Square". Besides the familiar slogans, whistling and booing can be heard in the crowd. The Revolution begins in Bucharest. Timișoara becomes the first city in Romania free of communism.
On the map: Bucharest.
Translated from the list on Wikipedia in Romanian.
21 December
Born on 21 December#
The English Wikipedia lists 178 births for this day. The blue points are the birthplaces of 60 of these people: those written about in the most Wikipedia editions, where Wikidata gives a place of birth.
Born on 21 December
1937
Jane Fonda, American actress and activist
Place of birth: New York City.
Born on 21 December
1917
Heinrich Böll, German novelist and short story writer, Nobel Prize laureate (died 1985)
Place of birth: Cologne.
Born on 21 December
1940
Frank Zappa, American singer-songwriter, guitarist, composer and producer (died 1993)
Place of birth: Baltimore.
Born on 21 December
1948
Samuel L. Jackson, American actor and producer
Place of birth: Washington, D.C..
Born on 21 December
1401
Masaccio, Italian painter (died 1428)
Place of birth: San Giovanni Valdarno.
Born in Britain and Ireland
1966
Kiefer Sutherland, British-Canadian actor, director, and producer
Place of birth: St Mary's Hospital.
Born in Britain and Ireland
1892
Rebecca West, English journalist and author (died 1983)
Place of birth: London.
Born in Britain and Ireland
1996
Ben Chilwell, English footballer
Place of birth: Milton Keynes.
21 December
Number one in the charts that week
At the cinema
An animal recorded that day
The record can be seen in GBIF, which brings together wildlife records from around the world.
All your birthdays
The weather that day
Data: Met Office Hadley Centre (HadCET); NOAA (GHCN-Daily, Mauna Loa).
Above the Earth
Sources: Jonathan McDowell, GCAT (launches); GFZ Potsdam (Kp index). Days are counted in Universal Time.
Football that day
International matches played that day:
Source: the “International football results” dataset kept by Mart Jürisoo (CC0).
Also that day
The earthquake’s page at the USGS
Source: the USGS catalogue. The day is counted in Universal Time (UTC).
In those days
Make a link for someone
Type the name, pick the day and the year of birth. The link opens straight on their day, with their name in the greeting.
The link carries the name, date and place typed here; anyone who gets it can see them.
Put another birthday beside it
Your mother’s, your child’s, a friend’s: the two days appear side by side.
Below: 21 December through the years.
The whole globe of the day
Drag the globe to turn it. Touch a ray or a point to read what happened there.
Everything Wikipedia lists for 21 December
The list is the English Wikipedia’s, in its own wording, as it stood in October 2026. 14 events have no place on the map: the sentence links to no place with coordinates, only to places too wide to mark, or to several countries.
- 69
The Roman Senate declares Vespasian emperor of Rome, the last in the Year of the Four Emperors.
Europe · Year of the Four EmperorsWikipedia: Year of the Four Emperors - 1124
Pope Honorius II is consecrated, having been elected after the controversial dethroning of Pope-Elect Celestine II.
no place on the mapWikipedia: Pope Honorius II - 1140
After a siege of several weeks, the city of Weinsberg and its castle surrender to Conrad III of Germany.
Europe · Siege of WeinsbergWikipedia: Siege of Weinsberg - 1237
The city of Ryazan is sacked by the Mongol army of Batu Khan.
Europe · Siege of RyazanWikipedia: Siege of Ryazan - 1361
The Battle of Linuesa is fought in the context of the Spanish Reconquista between the forces of the Emirate of Granada and the combined army of the Kingdom of Castile and of Jaén resulting in a Castilian victory.
Europe · Battle of LinuesaWikipedia: Battle of Linuesa - 1598
Battle of Curalaba: The revolting Mapuche, led by cacique Pelentaru, inflict a major defeat on Spanish troops in southern Chile.
Latin America · Battle of CuralabaWikipedia: Battle of Curalaba - 1620
Plymouth Colony: William Bradford and the Mayflower Pilgrims land near what is now known as Plymouth Rock in Plymouth, Massachusetts.
North America · Plymouth RockWikipedia: Plymouth Colony - 1812
The second earthquake to hit southern California in 13 days causes severe damage in Santa Barbara and Ventura.
North America · 1812 Ventura earthquakeWikipedia: 1812 Ventura earthquake - 1826
American settlers in Nacogdoches, Mexican Texas, declare their independence, starting the Fredonian Rebellion.
North America · NacogdochesWikipedia: Fredonian Rebellion - 1832
Egyptian–Ottoman War: Egyptian forces decisively defeat Ottoman troops at the Battle of Konya.
no place on the mapWikipedia: Battle of Konya - 1844
The Rochdale Society of Equitable Pioneers commences business at its cooperative in Rochdale, England, starting the Cooperative movement.
Britain & Ireland · RochdaleWikipedia: Rochdale Society of Equitable Pioneers - 1861
Medal of Honor: Public Resolution 82, containing a provision for a Navy Medal of Valor, is signed into law by President Abraham Lincoln.
no place on the mapWikipedia: Medal of Honor - 1872
Challenger expedition: HMS Challenger, commanded by Captain George Nares, sails from Portsmouth, England.
Britain & Ireland · PortsmouthWikipedia: Challenger expedition - 1879
the fictional character of Nora Helmer is first portrayed by Betty Hennings at a showing of A Doll's House at the Royal Danish Theatre.
no place on the mapWikipedia: A Doll's House - 1883
The Royal Canadian Dragoons and The Royal Canadian Regiment, the first Permanent Force cavalry and infantry regiments of the Canadian Army, are formed.
no place on the mapWikipedia: Royal Canadian Dragoons - 1907
The Chilean Army commits a massacre of at least 2,000 striking saltpeter miners in Iquique, Chile.
Latin America · Santa María School massacreWikipedia: Santa María School massacre - 1910
An underground explosion at the Hulton Bank Colliery No. 3 Pit in Over Hulton, Westhoughton, England, kills 344 miners.
Britain & Ireland · Pretoria Pit disasterWikipedia: Pretoria Pit disaster - 1911
Moscow's Cathedral of the Immaculate Conception was consecrated.
Europe · Cathedral of the Immaculate ConceptionWikipedia: Cathedral of the Immaculate Conception - 1919
American anarchist Emma Goldman is deported to Russia.
no place on the mapWikipedia: Anarchism - 1923
United Kingdom and Nepal formally sign an agreement of friendship, called the Nepal–Britain Treaty of 1923, which superseded the Treaty of Sugauli signed in 1816.
Asia · Singha DurbarWikipedia: Nepal–Britain Treaty of 1923 - 1934
Lieutenant Kijé, one of Sergei Prokofiev's best-known works, premiered.
no place on the mapWikipedia: Lieutenant Kijé - 1937
Snow White and the Seven Dwarfs, the first full-length cel-animated feature in film history, premiered at the Carthay Circle Theatre in Los Angeles.
North America · Carthay Circle TheatreWikipedia: Carthay Circle Theatre - 1941
World War II: A Thai-Japanese Pact of Alliance is signed.
no place on the mapWikipedia: World War II - 1946
An 8.1 Mw earthquake and subsequent tsunami in Nankaidō, Japan, kills over 1,300 people and destroys over 38,000 homes.
Asia · 1946 Nankai earthquakeWikipedia: 1946 Nankai earthquake - 1963
"Bloody Christmas" begins in Cyprus, ultimately resulting in the displacement of 25,000–30,000 Turkish Cypriots and destruction of more than 100 villages.
no place on the mapWikipedia: Bloody Christmas - 1965
International Convention on the Elimination of All Forms of Racial Discrimination is adopted.
- 1967
Louis Washkansky, the first man to undergo a human-to-human heart transplant, dies in Cape Town, South Africa, having lived for 18 days after the transplant.
Africa · Cape TownWikipedia: Louis Washkansky - 1968
Apollo program: Apollo 8 is launched from the Kennedy Space Center, placing its crew on a lunar trajectory for the first visit to another celestial body by humans.
North America · Kennedy Space CenterWikipedia: Apollo program - 1973
The Geneva Conference on the Arab–Israeli conflict opens.
Europe · GenevaWikipedia: Geneva Conference - 1979
Lancaster House Agreement: An independence agreement for Rhodesia is signed in London by Lord Carrington, Sir Ian Gilmour, Robert Mugabe, Joshua Nkomo, Bishop Abel Muzorewa and S.C. Mundawarara.
Britain & Ireland · Lancaster HouseWikipedia: Lancaster House Agreement - 1988
A bomb explodes on board Pan Am Flight 103 over Lockerbie, Dumfries and Galloway, Scotland, killing 270. This is to date the deadliest air disaster to occur on British soil.
Britain & Ireland · Pan Am Flight 103Wikipedia: Pan Am Flight 103 - 1988
The world's heaviest aircraft, the Antonov An-225 Mriya, made its first flight.
no place on the mapWikipedia: Antonov An-225 Mriya - 1991
Dissolution of the Soviet Union: The leaders of 11 now effectively autonomous Soviet republics sign the Alma-Ata Protocol establishing the Commonwealth of Independent States in place of the collapsing Soviet Union.
Asia · Dissolution of the Soviet UnionWikipedia: Dissolution of the Soviet Union - 1992
A Dutch DC-10, flight Martinair MP 495, crashes at Faro Airport, Portugal, killing 56.
Europe · Martinair Flight 495Wikipedia: Martinair Flight 495 - 1994
Mexico's Popocatépetl volcano, dormant for 47 years, began erupting, and is now one of the nation's most active volcanoes.
Latin America · PopocatépetlWikipedia: Popocatépetl - 1995
The city of Bethlehem passes from Israeli to Palestinian control.
Asia · BethlehemWikipedia: Israel - 1999
Cubana de Aviación Flight 1216 overshoots the runway at La Aurora International Airport, killing 18.
Latin America · Cubana de Aviación Flight 1216Wikipedia: Cubana de Aviación Flight 1216 - 1999
The Spanish Civil Guard intercepts a van loaded with 950 kg of explosives that ETA intended to use to blow up Torre Picasso in Madrid, Spain.
Europe · Torre PicassoWikipedia: Civil Guard - 2004
Iraq War: A suicide bomber kills 22 at the forward operating base next to the main U.S. military airfield at Mosul, Iraq, the single deadliest suicide attack on American soldiers in Iraq.
Asia · 2004 Forward Operating Base Marez bombingWikipedia: 2004 Forward Operating Base Marez bombing - 2012
2012 phenomenon: Festivities are held in parts of Mesoamerica to commemorate the conclusion of b'ak'tun 13, a roughly 5,126-year-long cycle in the Mesoamerican Long Count Calendar whose passing many New Age spiritualists had earlier held to portend a variety of cataclysmic or transformative events.
no place on the mapWikipedia: 2012 phenomenon - 2018
Operatives of the British Special Boat Service boarded the container ship Grande Tema in the Thames Estuary to detain four stowaways who had threatened the crew.
Britain & Ireland · Thames EstuaryWikipedia: Grande Tema incident - 2020
A great conjunction of Jupiter and Saturn occurs, with the two planets separated in the sky by 0.1 degrees. This is the closest conjunction between the two planets since 1623.
no place on the mapWikipedia: Great conjunction - 2022
A Vega C rocket carrying two Pléiades Neo satellites fails after liftoff.
no place on the mapWikipedia: Vega C - 2023
Fourteen people are killed and 25 others injured during a mass shooting at Charles University in Prague, Czech Republic.
Europe · 2023 Prague shootingsWikipedia: 2023 Prague shootings
What the other Wikipedias remember
For these years the English list has nothing on this day. The events below come from the same day’s lists on Wikipedia in Chinese and Romanian and were translated for this page.
- 1962
Rondane National Park, Norway's first national park, is officially established.
- 1989
The Romanian Revolution. In Bucharest, Nicolae Ceaușescu holds a rally in what is now "Revolution Square". Besides the familiar slogans, whistling and booing can be heard in the crowd. The Revolution begins in Bucharest. Timișoara becomes the first city in Romania free of communism.
Who was born on 21 December
In order of how many Wikipedia editions have an article about each. The first 60 of 178 are shown.
- 1977
Emmanuel Macron, French politician, 25th President of France
- 1804
Benjamin Disraeli, English lawyer and politician, Prime Minister of the United Kingdom (died 1881)
- 1937
Jane Fonda, American actress and activist
New York CityWikipedia: Jane Fonda - 1942
Hu Jintao, Chinese engineer and politician, 5th Paramount leader of China
Jiangyan DistrictWikipedia: Hu Jintao - 1967
Mikheil Saakashvili, Georgian lawyer and politician, 3rd President of Georgia
- 1917
Heinrich Böll, German novelist and short story writer, Nobel Prize laureate (died 1985)
CologneWikipedia: Heinrich Böll - 1940
Frank Zappa, American singer-songwriter, guitarist, composer and producer (died 1993)
BaltimoreWikipedia: Frank Zappa - 1948
Samuel L. Jackson, American actor and producer
Washington, D.C.Wikipedia: Samuel L. Jackson - 1949
Thomas Sankara, Burkinabé captain and politician, 5th President of Burkina Faso (died 1987)
- 1918
Kurt Waldheim, Austrian colonel and politician; 9th President of Austria (died 2007)
Sankt Andrä-WördernWikipedia: Kurt Waldheim - 1401
Masaccio, Italian painter (died 1428)
San Giovanni ValdarnoWikipedia: Masaccio - 1966
Kiefer Sutherland, British-Canadian actor, director, and producer
St Mary's HospitalWikipedia: Kiefer Sutherland - 1795
Leopold von Ranke, German historian, author, and academic (died 1886)
- 1954
Chris Evert, American tennis player and coach
Fort LauderdaleWikipedia: Chris Evert - 1896
Konstantin Rokossovsky, Marshal of the Soviet Union during World War II (died 1968)
CieliachanyWikipedia: Konstantin Rokossovsky - 1947
Paco de Lucía, Spanish guitarist, songwriter, and producer (died 2014)
AlgecirasWikipedia: Paco de Lucía - 1969
Julie Delpy, French model, actress, director, and screenwriter
14th arrondissement of ParisWikipedia: Julie Delpy - 1890
Hermann Joseph Muller, American geneticist and biologist, Nobel Prize laureate (died 1967)
ManhattanWikipedia: Hermann Joseph Muller - 1966
William Ruto, 5th President of Kenya
Uasin Gishu CountyWikipedia: William Ruto - 1892
Rebecca West, English journalist and author (died 1983)
LondonWikipedia: Rebecca West - 1959
Florence Griffith Joyner, American sprinter and actress (died 1998)
Los AngelesWikipedia: Florence Griffith Joyner - 1965
Andy Dick, American actor and comedian
CharlestonWikipedia: Andy Dick - 1989
Tamannaah, Indian actress
- 1996
Ben Chilwell, English footballer
Milton KeynesWikipedia: Ben Chilwell - 1983
Steven Yeun, American actor
- 1996
Kaitlyn Dever, American actress
PhoenixWikipedia: Kaitlyn Dever - 1957
Ray Romano, American actor, producer, and screenwriter
QueensWikipedia: Ray Romano - 1840
Namık Kemal, Turkish journalist, playwright, and activist (died 1888)
TekirdağWikipedia: Namık Kemal - 1805
Thomas Graham, Scottish chemist and academic (died 1869)
GlasgowWikipedia: Thomas Graham - 1878
Jan Łukasiewicz, Polish-Irish mathematician and philosopher (died 1956)
- 1981
Cristian Zaccardo, Italian footballer
FormigineWikipedia: Cristian Zaccardo - 1935
John G. Avildsen, American director, producer, and cinematographer (died 2017)
Oak ParkWikipedia: John G. Avildsen - 1951
Steve Perryman, English footballer and manager
- 1815
Thomas Couture, French painter and educator (died 1879)
- 1963
Govinda, Indian actor, singer, and politician
MumbaiWikipedia: Govinda - 1603
Roger Williams, English minister, theologian, and politician, 9th President of the Colony of Rhode Island (died 1684)
- 1920
Alicia Alonso, Cuban ballerina and choreographer, founded the Cuban National Ballet (died 2019)
HavanaWikipedia: Alicia Alonso - 1965
Anke Engelke, Canadian-German actress, director, and screenwriter
MontrealWikipedia: Anke Engelke - 1997
Madelyn Cline, American actress and model
Goose CreekWikipedia: Madelyn Cline - 1973
Matías Almeyda, Argentine footballer and manager
Buenos AiresWikipedia: Matías Almeyda - 1953
András Schiff, Hungarian-English pianist and conductor
BudapestWikipedia: András Schiff - 1950
Jeffrey Katzenberg, American screenwriter and producer, co-founded DreamWorks Animation
New York CityWikipedia: Jeffrey Katzenberg - 1955
Jane Kaczmarek, American actress
MilwaukeeWikipedia: Jane Kaczmarek - 1991
Riccardo Saponara, Italian footballer
- 1596
Peter Mohyla, Ruthenian Orthodox metropolitan and saint (died 1646)
SuceavaWikipedia: Petro Mohyla - 1866
Maud Gonne, Irish nationalist and political activist (died 1953)
FarnhamWikipedia: Maud Gonne - 1889
Sewall Wright, American geneticist and biologist (died 1988)
MelroseWikipedia: Sewall Wright - 1922
Paul Winchell, American actor, voice artist, and ventriloquist (died 2005)
New York CityWikipedia: Paul Winchell - 1958
Tamara Bykova, Russian high jumper
- 1859
Gustave Kahn, French poet and critic (died 1936)
- 1905
Anthony Powell, English author (died 2000)
- 1926
Arnošt Lustig, Czech author and playwright (died 2011)
PragueWikipedia: Arnošt Lustig - 2002
Clara Tauson, Danish tennis player
GentofteWikipedia: Clara Tauson - 1935
Lorenzo Bandini, Italian racing driver (died 1967)
encampment of Al MarjWikipedia: Lorenzo Bandini - 1935
Phil Donahue, American talk show host and producer (died 2024)
ClevelandWikipedia: Phil Donahue - 1978
Rutina Wesley, American actress
Las VegasWikipedia: Rutina Wesley - 1985
Tom Sturridge, English actor
LambethWikipedia: Tom Sturridge - 1850
Zdeněk Fibich, Czech composer and poet (died 1900)
VšebořiceWikipedia: Zdeněk Fibich - 1946
Carl Wilson, American singer-songwriter and guitarist (died 1998)
HawthorneWikipedia: Carl Wilson - 2006
Cooper Flagg, American basketball player
NewportWikipedia: Cooper Flagg
What is celebrated on 21 December
- Armed Forces Day (Philippines)
- Christian feast day: O Oriens
- Christian feast day: Peter Canisius
- Christian feast day: Thomas the Apostle
- Christian feast day: December 21 (Eastern Orthodox liturgics)
- Forefathers' Day (Plymouth, Massachusetts)
- São Tomé Day (São Tomé and Príncipe)
A greeting link for someone
Type a name and, if you like, the year of birth. The link opens with a greeting, and beside each event it says how old the person turned that day, or how many years before their birth it happened.
The name and the year go only into the link you send.
All 366 days
How the globe is made
Where the events come from
Each edition of this page uses the day’s list from Wikipedia in its own language: Romanian, English, Spanish, Chinese. The lists are written by volunteers and differ from one edition to the next; the text of each event is Wikipedia’s, with a link to the article. A row that appears twice in a list is shown once. The lists have not been checked event by event: they are Wikipedia’s, mistakes included.
For events before 1582, and for countries that moved to the Gregorian calendar later (Britain in 1752, Russia in 1918), the same day may be counted Old Style in one list and New Style in another.
The chapter “What the other Wikipedias remember” adds up to five events a day from the lists of the other three editions, only for years in which the English list has nothing on that day. They were translated for this page, passed the same filters as the tour, and are not counted among the events of the English list.
How an event gets onto the map
The place comes from Wikidata. If the sentence links to the article about the event itself (a battle, an opening, an earthquake), dated to the same year, the ray stands on its coordinates or on those of its location. Otherwise it stands on the first place the sentence links to: a town, a building, a mountain, an island. This second step can be wrong: sometimes the sentence only mentions the place. That is why the page says, under each event, which place the ray stands on.
When the sentence links to a single state or province, or to a single sea, lake or desert larger than 5,000 km², the globe shows a dashed circle, not a ray. The circle has the area Wikidata gives, with its radius kept between 1.2° and 16°, or a radius of 4.5° when Wikidata gives no area; it says only that the sentence links to that place. Organisations, ships, spacecraft, museum objects, rivers, mountain ranges, languages and continents are never used as places. When a sentence names several states and no exact place, the event stays in the list only.
What the height means
The height of a ray shows how many years have passed, on a logarithmic scale: 10 years, 100 years and 1,000 years are equal steps apart; anything older than about 2,600 years has the tallest ray. The colour runs from pale yellow for recent years to violet for antiquity.
Where the tour stops
In each region the tour stops at up to three events (five in Britain and Ireland), chosen mainly by three things: whether Wikipedia’s editors put the event in the “On this day” box of their main page (the English, Spanish and Chinese editions), how many Wikipedia editions have an article about it, and how many of the four lists include it. Events whose sentence or article is about a war, an attack, a crime or a disaster are left out of the tour; they stay in the whole list, in Wikipedia’s wording. The filter is a list of words and a list of Wikidata types, so it can miss some.
The tour of births names the people with articles in the most editions and leaves aside those whom the list or Wikidata describes as rulers, politicians, commanders, leaders of movements or criminals; they stay in the list.
The Earth and the Sun
The daytime images are NASA’s Blue Marble Next Generation mosaics, one for each month of 2004; the night side is Black Marble 2016. The tilt of the line between day and night is computed for the day; the hour is chosen so that the place being read is in daylight. The latitude where the Sun stands overhead is the average of the four years of the leap cycle; in a given year it can differ by up to 0.4°.
The day you were born
The number ones come from the weekly lists on Wikipedia: Billboard for the United States (from 1940; the Hot 100 from August 1958), the UK Singles Chart (from November 1952), Los 40 Principales for Spain (from July 1966) and, for Romania, the Romanian Top 100 and Airplay 100 (2001–2021, with missing weeks). The page shows the chart of the week in which the day of birth falls, with its date; Billboard and the UK chart are dated at the end of their week. For Romania before 2001 and for China these sources have no weekly chart.
The films are those that reached cinemas in the United States up to ten days before or three days after that day (some of them in a few cinemas at first), from the English Wikipedia’s yearly lists (from 1968), in order of how many editions have an article about them. The events “in those days” are the ones on the neighbouring days’ lists that carry the year of birth, passed through the same filter as the tour.
The day of birth, year included
The Moon, the star sign and the constellation are worked out by the page itself, for noon Universal Time on the day. The lit part of the Moon is rounded and can differ by a few per cent from that at the hour of birth. The sign follows the usual zodiac of twelve equal parts starting at the March equinox; the constellation is the one the Sun actually stood in front of, by the borders set by the International Astronomical Union, and within a day of a border the page does not name it. When the Sun changes sign while it is that day anywhere on Earth, the page gives the moment of crossing, rounded to ten minutes and accurate to within about a quarter of an hour, and the clock time in a few cities, with the time zone and summer time of that year.
The year in the Chinese calendar is the one your device’s own calendar gives for the date, checked against the Hong Kong Observatory’s tables. “All your birthdays” uses the same sources as the rest of the chapter for the same day in every year since the birth: the temperature, well-known launches that took place on that very day, matches of the teams the edition follows, snow deeper than 10 cm and strong geomagnetic storms. The three things at the top and the four on the picture are chosen in a fixed order (the song, the animal, a full Moon, a well-known launch before an ordinary earthquake); on the picture you can change them.
When the link carries a year of birth, the page adds a few things about that exact day. The weather is the Met Office’s Central England temperature record and the readings from New York’s Central Park; the “usual high” is the average of the daily highs of 1961–1990 for that date, with two days either side. The carbon dioxide figure is the monthly mean at the Mauna Loa observatory, where measurements begin in March 1958.
The earthquake is the one with the largest magnitude in the USGS catalogue for that day, counted in Universal Time. Before the 1960s the catalogue has gaps even above magnitude 5.5, so in the older years many days have no earthquake. The page gives only the magnitude and the place: the country the epicentre falls in or, when the epicentre is at sea within 300 km of a coast, the nearest country; farther out, only the ocean.
The launches are those that reached orbit or left for the Moon and the planets, from Jonathan McDowell’s GCAT catalogue. If nothing left that day, the page shows the nearest launch within three days before or after, and says how many days away it was. The geomagnetic storm appears only when the Kp index reached at least 5 in one of the day’s eight three-hour intervals.
The animal comes from GBIF: an observation made by a person (the animal seen or heard, or its tracks), dated to that exact day, with coordinates and a CC0 or CC BY licence. Only a few hundred well-known species are searched (mammals, birds, turtles, butterflies); of those noted that day, mammals and species with articles in many Wikipedia editions come first; birds noted almost every day, and species used recently, wait their turn. Observations dated 1 January are left out, because records without a day are often filed there. An observation shows that the animal was recorded there, not how many animals there were.
The matches are those between national teams. Only matches of England, Scotland, Wales, Northern Ireland, the Republic of Ireland, the United States, Canada and Australia are shown, along with those at the big final tournaments. The picture to send is drawn in the page from the day’s globe and the facts above, and stays on your device until you send it.
Sources
- Events, births and holidays: the day’s page on Wikipedia, text under CC BY-SA 4.0.
- Coordinates, places of birth and the number of editions: Wikidata (CC0).
- The Earth by day: NASA Blue Marble Next Generation. The Earth by night: NASA Black Marble 2016.
- Borders and regions: Natural Earth.
- World population and births per year: UN World Population Prospects 2024.
- Charts and films: Wikipedia’s lists for Billboard, the UK Singles Chart, Los 40 Principales, Romanian Top 100, Airplay 100 and American films by year (CC BY-SA 4.0).
- Weather: Met Office Hadley Centre, HadCET (Open Government Licence) and NOAA GHCN-Daily, New York Central Park. Carbon dioxide: NOAA Global Monitoring Laboratory, Mauna Loa.
- Earthquakes: the USGS catalogue. Launches: Jonathan McDowell, GCAT (CC BY). Kp index: GFZ Potsdam (CC BY 4.0). Matches: International football results, Mart Jürisoo (CC0).
- Animal observations: GBIF, with a link to each record; species names come from Wikidata.