A birthday on the globe
4 April on the globe: what happened in the world on this day, and who was born
For 4 April, the English Wikipedia lists 69 events and 300 births. 34 of the events stand at their places as rays of light; 10 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 4 April through the years
The Earth on 4 April
The picture on the globe was assembled by NASA from satellite photographs taken in April 2004: the snow, the ice and the green are those of the month.
On 4 April the Sun passes straight overhead at noon along the parallel of 5.9° north. In London, the day lasts about 13 hours 10 minutes.
Beyond 84° north the Sun no longer sets; beyond 84° south 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 · London
1958
The CND peace symbol is displayed in public for the first time in London.
On the map: London.
Also on the day’s list of Wikipedia in Spanish.
Asia · Constantinople
1268
A five-year Byzantine–Venetian peace treaty is concluded between Venetian envoys and Emperor Michael VIII Palaiologos.
On the map: Constantinople.
Also on the day’s list of Wikipedia in Chinese.
North America · United States Congress
1818
The United States Congress, affirming the Second Continental Congress, adopts the flag of the United States with 13 red and white stripes and one star for each state (20 at that time).
On the map: United States Congress.
North America · World Trade Center
1973
The Twin Towers of the World Trade Center in New York City are officially dedicated.
On the map: World Trade Center.
Also on the day’s list of Wikipedia in Spanish and Chinese.
North America · Albuquerque, New Mexico
1975
Microsoft is founded as a partnership between Bill Gates and Paul Allen in Albuquerque, New Mexico.
On the map: Albuquerque, New Mexico.
Also on the day’s list of Wikipedia in Spanish.
4 April
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 · Basel
1460
In Basel (northern Switzerland), Pope Pius II founds the University of Basel.
On the map: Basel.
Translated from the list on Wikipedia in Spanish.
4 April
Born on 4 April#
The English Wikipedia lists 300 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 4 April
1928
Maya Angelou, American memoirist and poet (died 2014)
Place of birth: St. Louis.
Born on 4 April
1965
Robert Downey Jr., American actor, producer, and screenwriter.
Place of birth: Greenwich Village.
Born on 4 April
1979
Heath Ledger, Australian actor (died 2008)
Place of birth: Perth.
Born on 4 April
1932
Andrei Tarkovsky, Russian director and producer (died 1986)
Place of birth: Zavrazhye.
Born on 4 April
1914
Marguerite Duras, French novelist, screenwriter, and director (died 1996)
Place of birth: Gia Định.
Born in Britain and Ireland
1952
Gary Moore, Northern Irish singer-songwriter, guitarist, and producer (died 2011)
Place of birth: Belfast.
Born in Britain and Ireland
1818
Thomas Mayne Reid, Irish-American author and poet (died 1883)
Place of birth: Ballyroney.
Born in Britain and Ireland
1986
Aiden McGeady, Scottish-born Irish footballer
Place of birth: Rutherglen.
4 April
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: 4 April 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 4 April
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.
- 503 BC
Roman consul Agrippa Menenius Lanatus celebrates a triumph for a military victory over the Sabines.
no place on the mapWikipedia: Roman consul - 190
Dong Zhuo has his troops evacuate the capital Luoyang and burn it to the ground.
Asia · LuoyangWikipedia: Dong Zhuo - 611
Maya king Uneh Chan of Calakmul sacks rival city-state Palenque in southern Mexico.
Latin America · CalakmulWikipedia: Scroll Serpent - 619
The Bijapur-Mumbai inscription is issued by Pulakeshin II, describing the Battle of Narmada.: 207
no place on the mapWikipedia: Pulakeshin II - 801
King Louis the Pious captures Barcelona from the Moors after a siege of several months.
Europe · BarcelonaWikipedia: Siege of Barcelona - 1081
The Komnenos dynasty came to full power with the coronation of Alexios I Komnenos as Byzantine emperor.
Asia · Byzantine EmpireWikipedia: Komnenos - 1268
A five-year Byzantine–Venetian peace treaty is concluded between Venetian envoys and Emperor Michael VIII Palaiologos.
Asia · ConstantinopleWikipedia: Byzantine–Venetian treaty of 1268 - 1423
Death of the Venetian Doge Tommaso Mocenigo, under whose rule victories were achieved against the Kingdom of Hungary and against the Ottoman Empire at the Battle of Gallipoli (1416).
Asia · Battle of GallipoliWikipedia: Battle of Gallipoli - 1581
Francis Drake is knighted by Queen Elizabeth I for completing a circumnavigation of the world.
no place on the mapWikipedia: Francis Drake - 1609
Moriscos are expelled from the Kingdom of Valencia.
Europe · Kingdom of ValenciaWikipedia: Morisco - 1660
Declaration of Breda by King Charles II of Great Britain promises, among other things, a general pardon to all royalists and opponents of the monarchy for crimes committed during the English Civil War and the Interregnum.
no place on the mapWikipedia: English Civil War - 1796
Georges Cuvier delivers the first paleontological lecture.
no place on the mapWikipedia: Georges Cuvier - 1814
Napoleon abdicates (conditionally) for the first time and names his son Napoleon II as Emperor of the French, followed by unconditional abdication two days later.
no place on the mapWikipedia: Napoleon - 1818
The United States Congress, affirming the Second Continental Congress, adopts the flag of the United States with 13 red and white stripes and one star for each state (20 at that time).
North America · United States CongressWikipedia: United States Congress - 1841
William Henry Harrison dies of pneumonia, becoming the first President of the United States to die in office, and setting the record for the briefest administration. Vice President John Tyler succeeds Harrison as President.
no place on the mapWikipedia: William Henry Harrison - 1859
Bryant's Minstrels premiered the minstrel song "Dixie" in New York City as part of their blackface show.
no place on the mapWikipedia: Bryant's Minstrels - 1860
The declaration on the introduction of the Finnish markka as an official currency is read in different parts of the Grand Duchy of Finland.
Europe · Grand Duchy of FinlandWikipedia: Finnish markka - 1865
American Civil War: A day after Union forces capture Richmond, Virginia, U.S. President Abraham Lincoln visits the Confederate capital.
North America · Richmond, VirginiaWikipedia: American Civil War - 1866
Alexander II of Russia narrowly escapes an assassination attempt by Dmitry Karakozov in the city of Saint Petersburg.
Europe · Saint PetersburgWikipedia: Alexander II of Russia - 1873
The Kennel Club, the world's oldest kennel club, was founded in the United Kingdom after Sewallis Shirley became frustrated by trying to organise dog shows without a consistent set of rules.
no place on the mapWikipedia: Royal Kennel Club - 1887
Argonia, Kansas elects Susanna M. Salter as the first female mayor in the United States.
North America · Argonia, KansasWikipedia: Argonia, Kansas - 1894
Foyot bombing by the Russian or French state during the Ère des attentats.
Europe · Foyot bombingWikipedia: Foyot bombing - 1904
Two Ms ~7.1 earthquakes, among the largest in Europe, strike Bulgaria, killing over 200 people and causing destruction.
Europe · 1904 Kresna earthquakesWikipedia: 1904 Kresna earthquakes - 1905
In India, an earthquake hits the Kangra Valley, killing 20,000, and destroying most buildings in Kangra, McLeod Ganj and Dharamshala.
Asia · 1905 Kangra earthquakeWikipedia: 1905 Kangra earthquake - 1913
First Balkan War: Greek aviator Emmanouil Argyropoulos becomes the first pilot to die in the Hellenic Air Force when his plane crashes.
no place on the mapWikipedia: First Balkan War - 1920
The four-day Nebi Musa riots commence.
Asia · 1920 Nebi Musa riotsWikipedia: 1920 Nebi Musa riots - 1925
The Schutzstaffel (SS) is founded under Adolf Hitler's Nazi Party in Germany.
Europe · Weimar RepublicWikipedia: Schutzstaffel - 1933
U.S. Navy airship USS Akron is wrecked off the New Jersey coast due to severe weather.
North America · New JerseyWikipedia: United States Navy - 1944
World War II: First bombardment of oil refineries in Bucharest by Anglo-American forces kills 3,000 civilians.
Europe · BucharestWikipedia: Bombing of Bucharest in World War II - 1945
World War II: Soviet Red Army troops liberate Hungary from German occupation.
Europe · HungaryWikipedia: Red Army - 1945
World War II: United States Army troops capture Kassel.
Europe · Battle of KasselWikipedia: Battle of Kassel - 1945
World War II: United States Army troops liberate Ohrdruf forced labor camp in Germany.
Europe · Ohrdruf concentration campWikipedia: United States Army - 1946
Greek judge and archeologist Panagiotis Poulitsas is appointed Prime Minister of Greece in the midst of the Greek Civil War.
no place on the mapWikipedia: Greek Civil War - 1949
Cold War: Twelve nations sign the North Atlantic Treaty creating the North Atlantic Treaty Organization.
North America · Washington, D.C.Wikipedia: North Atlantic Treaty - 1958
The CND peace symbol is displayed in public for the first time in London.
Britain & Ireland · LondonWikipedia: Campaign for Nuclear Disarmament - 1960
France agrees to grant independence to the Mali Federation, a union of Senegal and French Sudan.
no place on the mapWikipedia: France - 1963
Bye Bye Birdie, a musical romantic comedy film directed by George Sidney, was released.
no place on the mapWikipedia: Bye Bye Birdie - 1964
The Beatles occupy the top five positions on the Billboard Hot 100 pop chart.
no place on the mapWikipedia: The Beatles - 1967
Martin Luther King Jr. delivers his "Beyond Vietnam: A Time to Break Silence" speech in New York City's Riverside Church.
North America · Riverside ChurchWikipedia: Martin Luther King Jr. - 1968
Apollo program: NASA launches Apollo 6.
no place on the mapWikipedia: Apollo program - 1968
Martin Luther King Jr. is assassinated by James Earl Ray at a motel in Memphis, Tennessee.
North America · Assassination of Martin Luther King Jr.Wikipedia: Assassination of Martin Luther King Jr. - 1969
Dr. Denton Cooley implants the first temporary artificial heart.
no place on the mapWikipedia: Denton Cooley - 1973
A Lockheed C-141 Starlifter, dubbed the Hanoi Taxi, makes the last flight of Operation Homecoming.
Asia · South VietnamWikipedia: Operation Homecoming - 1973
The Twin Towers of the World Trade Center in New York City are officially dedicated.
North America · World Trade CenterWikipedia: World Trade Center - 1975
Microsoft is founded as a partnership between Bill Gates and Paul Allen in Albuquerque, New Mexico.
North America · Albuquerque, New MexicoWikipedia: Microsoft - 1975
Vietnam War: A United States Air Force Lockheed C-5A Galaxy transporting orphans, crashes near Saigon, South Vietnam shortly after takeoff, killing 172 people.
Asia · Operation BabyliftWikipedia: Vietnam War - 1977
Southern Airways Flight 242 crashes in New Hope, Paulding County, Georgia, killing 72.
North America · Southern Airways Flight 242Wikipedia: Southern Airways Flight 242 - 1979
Prime Minister Zulfikar Ali Bhutto of Pakistan is executed.
no place on the mapWikipedia: Zulfikar Ali Bhutto - 1981
Iran–Iraq War: The Islamic Republic of Iran Air Force mounts an attack on H-3 Airbase and destroys about 50 Iraqi aircraft.
Asia · H-3 airstrikeWikipedia: H-3 airstrike - 1983
Space Shuttle program: Space Shuttle Challenger makes its maiden voyage into space on STS-6.
no place on the mapWikipedia: Space Shuttle program - 1984
President Ronald Reagan calls for an international ban on chemical weapons.
no place on the mapWikipedia: Ronald Reagan - 1987
Garuda Indonesia Flight 032 crashes at Medan Airport, killing 23.
Asia · Soewondo Air Force BaseWikipedia: Garuda Indonesia Flight 035 - 1988
Governor Evan Mecham of Arizona is convicted in his impeachment trial and removed from office.
North America · ArizonaWikipedia: List of governors of Arizona - 1990
The current flag of Hong Kong is adopted for post-colonial Hong Kong during the Third Session of the Seventh National People's Congress.
no place on the mapWikipedia: Flag of Hong Kong - 1991
Forty-one people are taken hostage inside a Good Guys! Electronics store in Sacramento, California. Three of the hostage takers and three hostages are killed.
North America · 1991 Sacramento hostage crisisWikipedia: 1991 Sacramento hostage crisis - 1991
Senator John Heinz of Pennsylvania and six others are killed when a helicopter collides with their airplane over an elementary school in Merion, Pennsylvania.
North America · 1991 Merion mid-air collisionWikipedia: 1991 Merion mid-air collision - 1994
Three people are killed when KLM Cityhopper Flight 433 crashes at Amsterdam Airport Schiphol.
Europe · KLM Cityhopper Flight 433Wikipedia: KLM Cityhopper Flight 433 - 1996
Comet Hyakutake is imaged by the USA Asteroid Orbiter Near Earth Asteroid Rendezvous.
no place on the mapWikipedia: Comet Hyakutake - 1997
Space Shuttle program: Space Shuttle Columbia is launched on STS-83. However, the mission is later cut short due to a fuel cell problem.
no place on the mapWikipedia: Space Shuttle Columbia - 2002
The MPLA government of Angola and UNITA rebels sign a peace treaty ending the Angolan Civil War.
no place on the mapWikipedia: Angolan Civil War - 2009
France announces its return to full participation of its military forces within NATO.
Europe · FranceWikipedia: NATO - 2010
A magnitude 7.2 earthquake hits south of the Mexico-USA border, killing at least two and damaging buildings across the two countries.
Latin America · 2010 Baja California earthquakeWikipedia: 2010 Baja California earthquake - 2011
Georgian Airways Flight 834 crashes at N'djili Airport in Kinshasa, killing 32.
Africa · Georgian Airways Flight 834Wikipedia: Georgian Airways Flight 834 - 2013
Seventy-four people are killed in a building collapse in Thane, India.
Asia · 2013 Thane building collapseWikipedia: 2013 Thane building collapse - 2017
Syria conducts an air strike on Khan Shaykhun using chemical weapons, killing 89 civilians.
Asia · Khan Shaykhun chemical attackWikipedia: Khan Shaykhun chemical attack - 2020
China holds a national day of mourning for martyrs who died in the fight against the novel coronavirus disease outbreak.
no place on the mapWikipedia: COVID-19 pandemic in mainland China - 2023
Finland becomes a member of NATO after Turkey accepts its membership request.
no place on the mapWikipedia: NATO - 2024
Russo-Ukrainian war: The Battle of Chasiv Yar begins.
Europe · Donetsk OblastWikipedia: Russo-Ukrainian war - 2025
The impeachment of President Yoon Suk Yeol of South Korea in response to his declaration of martial law is unanimously upheld by the country's Constitutional Court, ending his presidency.
Asia · Constitutional Court of KoreaWikipedia: 2024 South Korean martial law crisis
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.
- 1460
In Basel (northern Switzerland), Pope Pius II founds the University of Basel.
Who was born on 4 April
In order of how many Wikipedia editions have an article about each. The first 60 of 300 are shown.
- 1928
Maya Angelou, American memoirist and poet (died 2014)
St. LouisWikipedia: Maya Angelou - 1965
Robert Downey Jr., American actor, producer, and screenwriter.
Greenwich VillageWikipedia: Robert Downey Jr. - 1979
Heath Ledger, Australian actor (died 2008)
- 1932
Andrei Tarkovsky, Russian director and producer (died 1986)
ZavrazhyeWikipedia: Andrei Tarkovsky - 188
Caracalla, Roman emperor (died 217)
LugdunumWikipedia: Caracalla - 1914
Marguerite Duras, French novelist, screenwriter, and director (died 1996)
Gia ĐịnhWikipedia: Marguerite Duras - 1987
Sami Khedira, German footballer
StuttgartWikipedia: Sami Khedira - 1884
Isoroku Yamamoto, Japanese admiral (died 1943)
NagaokaWikipedia: Isoroku Yamamoto - 1948
Abdullah Öcalan, Turkish activist
- 1932
Anthony Perkins, American actor (died 1992)
New York CityWikipedia: Anthony Perkins - 1960
Hugo Weaving, Nigerian-Australian actor and producer
IbadanWikipedia: Hugo Weaving - 1952
Gary Moore, Northern Irish singer-songwriter, guitarist, and producer (died 2011)
BelfastWikipedia: Gary Moore - 1785
Bettina von Arnim, German author, illustrator, and composer (died 1859)
FrankfurtWikipedia: Bettina von Arnim - 1913
Muddy Waters, American singer-songwriter and guitarist (died 1983)
Issaquena CountyWikipedia: Muddy Waters - 1846
Comte de Lautréamont, Uruguayan-French poet and educator (died 1870)
MontevideoWikipedia: Comte de Lautréamont - 1957
Aki Kaurismäki, Finnish director, producer, and screenwriter
OrimattilaWikipedia: Aki Kaurismäki - 1853
Remy de Gourmont, French poet, novelist, and critic (died 1915)
Bazoches-au-HoulmeWikipedia: Remy de Gourmont - 1945
Daniel Cohn-Bendit, French-German educator and politician
MontaubanWikipedia: Daniel Cohn-Bendit - 1818
Thomas Mayne Reid, Irish-American author and poet (died 1883)
BallyroneyWikipedia: Thomas Mayne Reid - 1819
Maria II of Portugal (died 1853)
Rio de JaneiroWikipedia: Maria II of Portugal - 1991
Jamie Lynn Spears, American actress and singer
- 1976
Emerson Ferreira da Rosa, Brazilian footballer
PelotasWikipedia: Emerson - 1892
Edith Södergran, Swedish-Finnish poet (died 1923)
Saint PetersburgWikipedia: Edith Södergran - 1876
Maurice de Vlaminck, French painter and poet (died 1958)
- 1986
Aiden McGeady, Scottish-born Irish footballer
RutherglenWikipedia: Aiden McGeady - 1964
David Cross, American actor, producer, and screenwriter
RoswellWikipedia: David Cross - 1939
Hugh Masekela, South African trumpeter, flugelhornist, cornetist, composer, and singer (died 2018)
WitbankWikipedia: Hugh Masekela - 1948
Dan Simmons, American author (died 2026)
PeoriaWikipedia: Dan Simmons - 2003
Harvey Elliott, English footballer
ChertseyWikipedia: Harvey Elliott - 1963
Graham Norton, Irish actor and talk show host
ClondalkinWikipedia: Graham Norton - 1987
Sarah Gadon, Canadian actress
TorontoWikipedia: Sarah Gadon - 1646
Antoine Galland, French orientalist and archaeologist (died 1715)
- 1922
Elmer Bernstein, American composer and conductor (died 2004)
New York CityWikipedia: Elmer Bernstein - 1949
Shing-Tung Yau, Chinese-American mathematician and academic
ShantouWikipedia: Shing-Tung Yau - 1979
Natasha Lyonne, American actress
New York CityWikipedia: Natasha Lyonne - 1983
Amanda Righetti, American actress
St. GeorgeWikipedia: Amanda Righetti - 1944
Craig T. Nelson, American actor, director, producer, and screenwriter
SpokaneWikipedia: Craig T. Nelson - 1970
Barry Pepper, Canadian actor and producer
Campbell RiverWikipedia: Barry Pepper - 1996
Austin Mahone, American singer-songwriter and actor
San AntonioWikipedia: Austin Mahone - 1950
Christine Lahti, American actress and director
BirminghamWikipedia: Christine Lahti - 1964
Branco, Brazilian footballer and coach
- 1989
Vurnon Anita, Dutch footballer
WillemstadWikipedia: Vurnon Anita - 1973
David Blaine, American magician and producer
BrooklynWikipedia: David Blaine - 1985
Rudy Fernández, Spanish basketball player
- 1842
Édouard Lucas, French mathematician and theorist (died 1891)
AmiensWikipedia: Édouard Lucas - 1976
James Roday, American actor, director, and screenwriter
San AntonioWikipedia: James Roday Rodriguez - 1802
Dorothea Dix, American nurse and activist (died 1887)
HampdenWikipedia: Dorothea Dix - 1972
Jill Scott, American singer-songwriter and actress
PhiladelphiaWikipedia: Jill Scott - 1983
Eric André, American comedian
Boca RatonWikipedia: Eric André - 2001
Angelo Stiller, German footballer
- 1688
Joseph-Nicolas Delisle, French astronomer and cartographer (died 1768)
- 1923
Peter Vaughan, English actor (died 2016)
- 1932
Richard Lugar, American lieutenant and politician, 44th Mayor of Indianapolis (died 2019)
IndianapolisWikipedia: Richard Lugar - 1952
Rosemarie Ackermann, German high jumper
- 1772
Nachman of Breslov, Ukrainian founder of the Breslov Hasidic movement (died 1810)
MedzhybizhWikipedia: Nachman of Breslov - 1925
Dettmar Cramer, German footballer and manager (died 2015)
DortmundWikipedia: Dettmar Cramer - 1983
Ben Gordon, American basketball player
LondonWikipedia: Ben Gordon - 1985
Dudi Sela, Israeli tennis player
Kiryat ShmonaWikipedia: Dudi Sela - 1987
McDonald Mariga, Kenyan footballer
NairobiWikipedia: McDonald Mariga - 1898
Agnes Ayres, American actress (died 1940)
CarbondaleWikipedia: Agnes Ayres
What is celebrated on 4 April
- Children's Day (Hong Kong, Taiwan)
- Christian feast day: Benedict the Moor
- Christian feast day: Gaetano Catanoso
- Christian feast day: Isidore of Seville
- Christian feast day: Martin Luther King Jr. (Episcopal Church (USA))
- Christian feast day: Reginald Heber (Anglican Church of Canada)
- Christian feast day: Tigernach of Clones
- Christian feast day: Plato of Sakkoudion
- Christian feast day: April 4 (Eastern Orthodox liturgics)
- Independence Day, celebrates the independence of Senegal from France (1960).
- Peace Day (Angola)
- One of the possible days for Qingming Festival.
- NATO Day
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.