A birthday on the globe
21 September on the globe: what happened in the world on this day, and who was born
For 21 September, the English Wikipedia lists 63 events and 290 births. 29 of the events stand at their places as rays of light; nine more are dashed circles, where the sentence links only to a country or a sea. 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 September through the years
The Earth on 21 September
The picture on the globe was assembled by NASA from satellite photographs taken in September 2004: the snow, the ice and the green are those of the month.
On 21 September the Sun passes straight overhead at noon along the parallel of 0.7° north. In London, the day lasts about 12 hours 20 minutes.
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.
Latin America · Callao
1675
Led by Antonio de Vea, a Spanish naval expedition departed El Callao, Peru, for the fjords and channels of Patagonia to find whether rival colonial powers were in the region.
On the map: Callao.
North America · United States Congress
1996
The Defense of Marriage Act is passed by the United States Congress.
On the map: United States Congress.
21 September
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 Spanish and were translated for this page.
From Wikipedia in Spanish · Shroud of Turin
2002
The Holy Shroud, after remaining stored away for several decades, is shown to the press by the Cardinal Archbishop of Turin, Severino Poletto. The cloth is in a seriously deteriorated state.
On the map: Shroud of Turin.
Translated from the list on Wikipedia in Spanish.
21 September
Born on 21 September#
The English Wikipedia lists 290 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 September
1866
H. G. Wells, English novelist, historian, and critic (died 1946)
Place of birth: Bromley.
Born on 21 September
1947
Stephen King, American author and screenwriter
Place of birth: Portland.
Born on 21 September
1934
Leonard Cohen, Canadian singer-songwriter and poet (died 2016)
Place of birth: Montreal.
Born on 21 September
1853
Heike Kamerlingh Onnes, Dutch physicist and academic, Nobel Prize laureate (died 1926)
Place of birth: Groningen.
Born in Britain and Ireland
1874
Gustav Holst, English composer and educator (died 1934)
Place of birth: Cheltenham.
Born in Britain and Ireland
1972
Liam Gallagher, English singer-songwriter
Place of birth: Manchester.
Born in Britain and Ireland
1979
Richard Dunne, Irish footballer
Place of birth: Tallaght.
21 September
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 September 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 September
The list is the English Wikipedia’s, in its own wording, as it stood in October 2026. 25 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.
- 454
Western Roman Emperor Valentinian III murders his general Flavius Aetius on instigation of eunuch Heraclius and senator Petronius Maximus.
no place on the mapWikipedia: Roman emperor - 455
Emperor Avitus enters Italy with a Gallic army and consolidates his power.
Europe · ItalyWikipedia: Avitus - 1170
Anglo-Norman invasion of Ireland: The Kingdom of Dublin falls to Anglo-Norman invaders.
no place on the mapWikipedia: Anglo-Norman invasion of Ireland - 1217
Livonian Crusade: The Estonian leader Lembitu and Livonian leader Caupo of Turaida are killed in the Battle of St. Matthew's Day.
Europe · Battle of St. Matthew's DayWikipedia: Battle of St. Matthew's Day - 1435
The Treaty of Arras is promulgated, causing Burgundy to switch sides in the Hundred Years' War.
Europe · ArrasWikipedia: Congress of Arras - 1675
Led by Antonio de Vea, a Spanish naval expedition departed El Callao, Peru, for the fjords and channels of Patagonia to find whether rival colonial powers were in the region.
Latin America · CallaoWikipedia: Patagonia - 1745
A British government army led by Sir John Cope is defeated in less than 15 minutes by the Jacobite forces of Prince Charles Edward Stuart.
Britain & Ireland · Battle of PrestonpansWikipedia: Battle of Prestonpans - 1776
Part of New York City is burned shortly after being occupied by British forces.
North America · Great Fire of New YorkWikipedia: Great Fire of New York - 1780
American Revolutionary War: Benedict Arnold gives the British the plans to West Point.
no place on the mapWikipedia: American Revolutionary War - 1792
French Revolution: The National Convention abolishes the monarchy.
no place on the mapWikipedia: French Revolution - 1809
British Secretary of War Lord Castlereagh and Foreign Secretary George Canning meet in a duel on Putney Heath, with Castlereagh wounding Canning in the thigh.
Britain & Ireland · Wimbledon CommonWikipedia: Wimbledon Common - 1814
War of 1812: British forces abandon their unsuccessful siege of Fort Erie.
North America · Siege of Fort ErieWikipedia: War of 1812 - 1843
The crew of schooner Ancud, led by John Williams Wilson, takes possession of the Strait of Magellan on behalf of the Chilean government.
no place on the mapWikipedia: Chilean colonization of the Strait of Magellan - 1860
Second Opium War: An Anglo-French force defeats Chinese troops at the Battle of Palikao.
Asia · Battle of PalikaoWikipedia: Second Opium War - 1862
Taiping Rebellion: The Ever Victorious Army defeats Taiping forces at the Battle of Cixi.
Asia · Cixi CityWikipedia: Taiping Rebellion - 1896
Anglo-Egyptian conquest of Sudan: British forces under the command of Horatio Kitchener take Dongola.
Africa · DongolaWikipedia: Anglo-Egyptian conquest of Sudan - 1897
In response to a letter written by eight-year-old Virginia O'Hanlon, The New York Sun published an editorial by Francis Pharcellus Church stating, "Yes, Virginia, there is a Santa Claus".
no place on the mapWikipedia: The Sun - 1898
Empress Dowager Cixi seizes power and ends the Hundred Days' Reform in China.
Asia · Qing dynastyWikipedia: Hundred Days' Reform - 1918
World War I: The Battle of Nazareth ended with the British Empire victorious over the Ottomans.
Asia · Battle of NazarethWikipedia: World War I - 1921
A storage silo in Oppau, Germany, explodes, killing 500–600 people.
Europe · Oppau explosionWikipedia: Oppau explosion - 1933
Salvador Lutteroth establishes Mexican professional wrestling.
no place on the mapWikipedia: Salvador Lutteroth - 1934
A large typhoon hits western Honshū, Japan, killing more than 3,000 people.
Asia · HonshuWikipedia: 1934 Muroto typhoon - 1934
Chandrashekhar Agashe established the Brihan Maharashtra Sugar Syndicate Ltd., one of the oldest companies in India.
no place on the mapWikipedia: Chandrashekhar Agashe - 1937
J.R.R. Tolkien's The Hobbit is published for the first time. (September 22 is celebrated by some fans as Hobbit Day, however.)
no place on the mapWikipedia: J. R. R. Tolkien - 1938
The Great Hurricane of 1938 makes landfall on Long Island in New York. The death toll is estimated at 500–700 people.
North America · New YorkWikipedia: 1938 New England hurricane - 1939
Romanian prime minister Armand Călinescu is assassinated by the Iron Guard.
no place on the mapWikipedia: Armand Călinescu - 1942
The Boeing B-29 Superfortress makes its maiden flight.
no place on the mapWikipedia: Boeing B-29 Superfortress - 1942
The Holocaust in Poland: At the end of Yom Kippur, Germans order Jews to permanently move from Konstantynów to Biała Podlaska.
Europe · Biała PodlaskaWikipedia: The Holocaust in Poland - 1942
The Holocaust in Ukraine: In Dunaivtsi, Ukraine, Nazis murder 2,588 Jews.
Europe · DunaivtsiWikipedia: Dunaivtsi - 1942
The Holocaust in Ukraine: On the Jewish holiday of Yom Kippur, Nazis send over 1,000 Jews from Pidhaitsi to Bełżec extermination camp.
Europe · PidhaitsiWikipedia: The Holocaust in Ukraine - 1953
Lieutenant No Kum-sok, a North Korean pilot, defects to South Korea with his jet fighter.
no place on the mapWikipedia: No Kum-sok - 1957
Pamir, a four-masted barque, was shipwrecked and sank off the Azores during Hurricane Carrie.
Europe · AzoresWikipedia: Pamir - 1964
Malta gains independence from the United Kingdom, but remains in the Commonwealth.
no place on the mapWikipedia: Malta - 1964
The North American XB-70 Valkyrie, the world's fastest bomber, makes its maiden flight from Palmdale, California.
North America · Palmdale, CaliforniaWikipedia: North American XB-70 Valkyrie - 1965
Portugal accepted a diplomatic mission from Southern Rhodesia despite objections by Britain, which had required the colony to implement black majority rule as a condition of independence.
Africa · Southern RhodesiaWikipedia: Rhodesian mission in Lisbon - 1965
The Gambia, Maldives and Singapore are admitted as members of the United Nations.
no place on the mapWikipedia: The Gambia - 1968
The Soviet Union's Zond 5 landed in the Indian Ocean, becoming the first spacecraft to safely return to Earth after travelling around the Moon.
no place on the mapWikipedia: Zond 5 - 1969
Mexicana de Aviación Flight 801, a Boeing 727-100 passenger plane, crashes during a landing attempt in Mexico City, killing 27 of the 118 occupants.
Latin America · Aeropuerto Internacional Benito JuárezWikipedia: Mexicana de Aviación Flight 801 - 1971
Bahrain, Bhutan and Qatar join the United Nations.
no place on the mapWikipedia: Bahrain - 1972
Philippine president Ferdinand Marcos begins authoritarian rule by declaring martial law.
no place on the mapWikipedia: Ferdinand Marcos - 1976
Orlando Letelier is assassinated in Washington, D.C. by Michael Townley, linked to the National Intelligence Directorate of Chile.
North America · Assassination of Orlando LetelierWikipedia: Assassination of Orlando Letelier - 1976
Seychelles joins the United Nations.
Oceans · SeychellesWikipedia: Seychelles - 1977
Malév Flight 203 crashes near Urziceni, Romania, killing 29 people.
Europe · Malév Flight 203Wikipedia: Malév Flight 203 - 1981
Belize is granted full independence from the United Kingdom.
Latin America · BelizeWikipedia: Belize - 1981
Sandra Day O'Connor is unanimously approved by the U.S. Senate as the first female Supreme Court justice.
no place on the mapWikipedia: Sandra Day O'Connor - 1984
Brunei joins the United Nations.
Asia · BruneiWikipedia: Brunei - 1991
Armenia gains independence from the Soviet Union.
no place on the mapWikipedia: 1991 Armenian independence referendum - 1993
A Transair Georgian Airlines Tu-134 is shot down by a missile in the Black Sea near Sokhumi, Georgia.
Europe · Black SeaWikipedia: 1993 Sukhumi airliner attacks - 1993
Russian president Boris Yeltsin triggers a constitutional crisis when he suspends parliament and scraps the constitution.
Europe · MoscowWikipedia: 1993 Russian constitutional crisis - 1995
MIAT Flight 557 crashes near Mörön, Mongolia, killing 41 people.
Asia · MIAT Flight 557Wikipedia: MIAT Flight 557 - 1996
The Defense of Marriage Act is passed by the United States Congress.
North America · United States CongressWikipedia: United States Congress - 1997
St. Olaf's Church, a stone church from the 16th century in Tyrvää, Finland, is burnt down by a burglar.
Europe · St. Olaf's Church, TyrvääWikipedia: St. Olaf's Church, Tyrvää - 1999
The 7.7-magnitude Chi-Chi earthquake strikes central Taiwan, killing 2,400 people.
Asia · 1999 Jiji earthquakeWikipedia: 1999 Jiji earthquake - 1999
The first chapter of Naruto, later one of the best-selling manga series, was published.
no place on the mapWikipedia: Naruto - 2001
America: A Tribute to Heroes is broadcast by over 35 network and cable channels, raising over $200 million for the victims of the September 11 attacks.
no place on the mapWikipedia: America: A Tribute to Heroes - 2001
Ross Parker is murdered in Peterborough, England, by a gang of ten British Pakistani youths.
Britain & Ireland · Murder of Ross ParkerWikipedia: Murder of Ross Parker - 2003
The Galileo spacecraft is terminated by sending it into Jupiter's atmosphere.
no place on the mapWikipedia: Galileo - 2004
American rock band Green Day released their seventh studio album, American Idiot.
no place on the mapWikipedia: Green Day - 2012
Three Egyptian militants open fire on a group of Israeli soldiers in a southern Israel cross-border attack.
Asia · September 2012 southern Israel cross-border attackWikipedia: September 2012 southern Israel cross-border attack - 2013
Al-Shabaab Islamic militants attack the Westgate shopping mall in Kenya, killing at least 67 people.
Africa · Westgate shopping mall attackWikipedia: Westgate shopping mall attack - 2015
Adventist Health System agreed to pay $118.7 million to settle allegations of fraud. It was the largest a hospital network has ever paid.
no place on the mapWikipedia: AdventHealth - 2018
LGBT rights activist Zak Kostopoulos is beaten to death on a busy street in Athens.
no place on the mapWikipedia: Zak Kostopoulos - 2019
A 5.6 Mw earthquake shakes the Albanian port of Durrës. Forty-nine people are injured in the capital, Tirana.
Europe · 2019 Albania earthquakeWikipedia: 2019 Albania earthquake
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 Spanish and were translated for this page.
- 2002
The Holy Shroud, after remaining stored away for several decades, is shown to the press by the Cardinal Archbishop of Turin, Severino Poletto. The cloth is in a seriously deteriorated state.
Who was born on 21 September
In order of how many Wikipedia editions have an article about each. The first 60 of 290 are shown.
- 1866
H. G. Wells, English novelist, historian, and critic (died 1946)
BromleyWikipedia: H. G. Wells - 1954
Shinzo Abe, Japanese lawyer and politician, 90th Prime Minister of Japan (died 2022)
ShinjukuWikipedia: Shinzo Abe - 1909
Kwame Nkrumah, Ghanaian educator and politician, 1st President of Ghana (died 1972)
NkrofulWikipedia: Kwame Nkrumah - 1947
Stephen King, American author and screenwriter
PortlandWikipedia: Stephen King - 1934
Leonard Cohen, Canadian singer-songwriter and poet (died 2016)
MontrealWikipedia: Leonard Cohen - 1842
Abdul Hamid II, 34th Sultan of the Ottoman Empire (died 1918)
IstanbulWikipedia: Abdul Hamid II - 1980
Kareena Kapoor, Indian actress
- 1957
Kevin Rudd, Australian politician and diplomat, 26th Prime Minister of Australia
NambourWikipedia: Kevin Rudd - 1853
Heike Kamerlingh Onnes, Dutch physicist and academic, Nobel Prize laureate (died 1926)
GroningenWikipedia: Heike Kamerlingh Onnes - 1950
Bill Murray, American actor, comedian, producer, and screenwriter
WilmetteWikipedia: Bill Murray - 1452
Girolamo Savonarola, Italian priest and philosopher (died 1498)
- 1926
Donald A. Glaser, American physicist and neurobiologist, Nobel Prize laureate (died 2013)
ClevelandWikipedia: Donald Glaser - 580
Pope Vitalian (died 672)
- 1866
Charles Nicolle, French-Tunisian microbiologist and academic, Nobel Prize laureate (died 1936)
- 1951
Aslan Maskhadov, Chechen general and politician, 3rd President of the Chechen Republic of Ichkeria (died 2005)
- 1840
Murad V, Ottoman sultan (died 1904)
Topkapı PalaceWikipedia: Murad V - 1415
Frederick III, Holy Roman Emperor (died 1493)
- 1936
Yury Luzhkov, Russian soldier and politician, 2nd Mayor of Moscow (died 2019)
MoscowWikipedia: Yury Luzhkov - 1967
Suman Pokhrel, Nepali poet, lyricist and playwright
BiratnagarWikipedia: Suman Pokhrel - 1874
Gustav Holst, English composer and educator (died 1934)
CheltenhamWikipedia: Gustav Holst - 1999
Alexander Isak, Eritrean-Swedish professional footballer
StockholmWikipedia: Alexander Isak - 1931
Larry Hagman, American actor, director, and producer (died 2012)
Fort WorthWikipedia: Larry Hagman - 1967
Faith Hill, American singer-songwriter, producer, and actress
RidgelandWikipedia: Faith Hill - 1983
Maggie Grace, American actress
WorthingtonWikipedia: Maggie Grace - 1972
Liam Gallagher, English singer-songwriter
ManchesterWikipedia: Liam Gallagher - 1965
Frédéric Beigbeder, French author and critic
Neuilly-sur-SeineWikipedia: Frédéric Beigbeder - 1929
Sándor Kocsis, Hungarian footballer and manager (died 1979)
BudapestWikipedia: Sándor Kocsis - 1989
Jason Derulo, American singer-songwriter
MiramarWikipedia: Jason Derulo - 1993
Ante Rebić, Croatian footballer
- 1988
Bilawal Bhutto Zardari, Pakistani politician
- 1640
Philippe I, Duke of Orléans, younger son of Louis XIII of France and his wife (died 1701)
Saint-Germain-en-LayeWikipedia: Philippe I, Duke of Orléans - 1971
Luke Wilson, American actor, director, and screenwriter
DallasWikipedia: Luke Wilson - 1859
Francesc Macià, Catalan colonel and politician, 122nd President of Catalonia (died 1933)
Vilanova i la GeltrúWikipedia: Francesc Macià - 1970
Samantha Power, Irish-American journalist, academic, and diplomat, 28th United States Ambassador to the United Nations
- 1955
Israel Katz, Israeli politician
AshkelonWikipedia: Israel Katz - 1867
Henry L. Stimson, American colonel, lawyer, and politician, 46th United States Secretary of State (died 1950)
New York CityWikipedia: Henry L. Stimson - 1943
Jerry Bruckheimer, American film and television producer
DetroitWikipedia: Jerry Bruckheimer - 1983
Anna Favella, Italian actress
- 1979
Richard Dunne, Irish footballer
TallaghtWikipedia: Richard Dunne - 1986
Lindsey Stirling, American violinist and composer
Santa AnaWikipedia: Lindsey Stirling - 1990
Christian Serratos, American actress
PasadenaWikipedia: Christian Serratos - 1411
Richard of York, 3rd Duke of York, English politician, Lord Protector of England (died 1460)
Kings LangleyWikipedia: Richard of York, 3rd Duke of York - 1912
Chuck Jones, American animator, producer, and screenwriter (died 2002)
SpokaneWikipedia: Chuck Jones - 1981
Nicole Richie, American actress, fashion designer, and author
BerkeleyWikipedia: Nicole Richie - 1965
Cheryl Hines, American actress
Miami BeachWikipedia: Cheryl Hines - 1902
Luis Cernuda, Spanish poet and critic (died 1963)
SevilleWikipedia: Luis Cernuda - 1946
Moritz Leuenberger, Swiss lawyer and politician, 87th President of the Swiss Confederation
Biel/BienneWikipedia: Moritz Leuenberger - 1428
Jingtai Emperor of China (died 1457)
BeijingWikipedia: Jingtai Emperor - 1919
Mario Bunge, Argentinian-Canadian physicist and philosopher (died 2020)
Florida OesteWikipedia: Mario Bunge - 1953
Reinhard Marx, German cardinal
GesekeWikipedia: Reinhard Marx - 1987
Michał Pazdan, Polish footballer
KrakówWikipedia: Michał Pazdan - 1983
Joseph Mazzello, American actor, director, producer, and screenwriter
RhinebeckWikipedia: Joseph Mazzello - 1916
Françoise Giroud, Swiss-French journalist and politician, French Minister of Culture (died 2003)
LausanneWikipedia: Françoise Giroud - 1973
Virginia Ruano Pascual, Spanish tennis player
- 1974
Özgür Özel, Turkish pharmacist and politician
ManisaWikipedia: Özgür Özel - 1987
Ryan Guzman, American actor and model
AbileneWikipedia: Ryan Guzman - 1924
Hermann Buhl, Austrian mountaineer (died 1957)
InnsbruckWikipedia: Hermann Buhl - 1929
Bernard Williams, English-Italian philosopher and academic (died 2003)
Westcliff-on-SeaWikipedia: Bernard Williams - 1935
Jimmy Armfield, English footballer and manager (died 2018)
- 1980
Autumn Reeser, American actress
La JollaWikipedia: Autumn Reeser
What is celebrated on 21 September
- Autumnal equinox observances in the Northern Hemisphere, vernal equinox observances in the Southern Hemisphere (see September 22): Spring Day (Argentina)
- Christian feast day: Cadoc
- Christian feast day: Ephigenia of Ethiopia
- Christian feast day: Laurent-Joseph-Marius Imbert (one of the Korean Martyrs)
- Christian feast day: Matthew the Evangelist (Western Church)
- Christian feast day: Maura of Troyes
- Christian feast day: Nativity of the Theotokos (Eastern Orthodox Church, Julian calendar)
- Christian feast day: September 21 (Eastern Orthodox liturgics)
- Arbor Day (Brazil)
- Commemoration of the Declaration of Martial Law (Philippines)
- Customs Service Day (Poland)
- Founder's Day and National Volunteer Day (Ghana)
- Independence Day, celebrates the independence of Armenia from the Soviet Union in 1991.
- Independence Day, celebrates the independence of Belize from the United Kingdom in 1981.
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.