March 1 » Henri Becquerel discovers radioactive decay.
May 18 » The United States Supreme Court rules in Plessy v. Ferguson that the "separate but equal" doctrine is constitutional.
May 26 » Charles Dow publishes the first edition of the Dow Jones Industrial Average.
June 2 » Guglielmo Marconi applies for a patent for his wireless telegraph.
June 28 » An explosion in the Newton Coal Company's Twin Shaft Mine in Pittston, Pennsylvania results in a massive cave-in that kills 58 miners.
December 10 » Alfred Jarry's Ubu Roi premieres in Paris. A riot breaks out at the end of the performance.
Day of death April 21, 1980
The temperature on April 21, 1980 was between 3.2 °C and 9.6 °C and averaged 5.9 °C. There was 1.2 mm of rain during 1.2 hours. There was 4.7 hours of sunshine (33%). The partly or heavily clouded was. The average windspeed was 2 Bft (weak wind) and was prevailing from the north-northwest. Source: KNMI
In The Netherlands , there was from Monday, December 19, 1977 to Friday, September 11, 1981 the cabinet Van Agt I, with Mr. A.A.M. van Agt (CDA/KVP) as prime minister.
February 2 » Reports surface that the FBI is targeting allegedly corrupt Congressmen in the Abscam operation.
February 23 » Iran hostage crisis: Supreme Leader Ayatollah Ruhollah Khomeini states that Iran's parliament will decide the fate of the American embassy hostages.
April 2 » United States President Jimmy Carter signs the Crude Oil Windfall Profits Tax Act.
April 3 » US Congress restores a federal trust relationship with the 501 members of the Shvwits, Kanosh, Koosharem, and the Indian Peaks and Cedar City bands of the Paiute people of Utah.
April 30 » Beatrix is inaugurated as Queen of the Netherlands following the abdication of Juliana.
June 1 » Cable News Network (CNN) begins broadcasting.
When copying data from this family tree, please include a reference to the origin: Peeters Mathieu, "FutureHistory", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-riske/I5120.php : accessed February 9, 2026), "Maria Amelberga de Meirleir (1896-1980)".
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