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From today's featured article

Nuclear reaction theorised by Meitner and Frisch

Nuclear fission was discovered in December 1938 by physicists Lise Meitner and Otto Frisch, and chemists Otto Hahn and Fritz Strassmann. Fission is a nuclear reaction and process of radioactive decay in which the nucleus of an atom splits into two or more smaller, lighter nuclei. The fission process releases a very large amount of energy. The discovery that a nuclear chain reaction was possible led to the development of nuclear power and nuclear weapons. Hahn and Strassmann bombarded uranium with slow neutrons, and discovered that barium had been produced (illustration pictured). Meitner and her nephew Frisch theorised, and then proved, that the uranium nucleus had been split, and published their findings in Nature. Meitner calculated that the energy released by each disintegration was approximately 200 megaelectronvolts, and Frisch observed this. By analogy with the division of biological cells, Frisch named the process "fission". Hahn was awarded the 1944 Nobel Prize in Chemistry for the discovery. (Full article...)

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Did you know ...

Esplanade Mansions

... that Esplanade Mansions (pictured) is the only building in Kolkata in the Art Nouveau architectural style?
... that John Quincy Adams was the only American president to be elected as a member of House of Representatives after leaving the presidency?
... that the Toba people use poultices made from the manure of the black-legged seriema to treat boils and abscesses?
... that China expert Sasaki Tōichi was chastised for referring to Sun Yat-sen with the honorific sensei?
... that in 1981 the Conservative Party leadership feared that 25 of its members of parliament would vote against Margaret Thatcher's economic policies and cause a split in the party?
... that in 1929, Lisl Goldarbeiter became the first Austrian to win the Miss Universe title?
... that Malcolm Gladwell's The Bomber Mafia, about the Bomber Mafia of World War II, concludes that "LeMay won the battle. [...] Hansell won the war" with regard to high-precision aerial bombing?
... that Sae Eun Park is the first Asian étoile at the Paris Opera Ballet, and one of the few foreigners to hold the title?

In the news

Ebrahim Raisi

In golf, Jon Rahm wins the U.S. Open.
Ebrahim Raisi (pictured) is elected president of Iran.
China's Shenzhou 12 launches with the first crew to dock at the Tiangong space station.
Kenneth Kaunda, the first president of Zambia, dies at the age of 97.
A new government is formed in Israel, with Naftali Bennett becoming prime minister, ending Benjamin Netanyahu's 12-year tenure.

On this day

June 22

King George V and Queen Mary

1593 – Ottoman forces were crushingly defeated by the Habsburgs at Sisak (in present-day Croatia), triggering the Long Turkish War.
1813 – War of 1812: After learning of a forthcoming American attack, Laura Secord walked 20 mi (32 km) from Queenston, Upper Canada, to warn British lieutenant James FitzGibbon.
1911 – King George V and Queen Mary of Teck (both pictured) were crowned at Westminster Abbey in London.
1941 – World War II: As Axis troops began their invasion of the Soviet Union, the Lithuanian Activist Front started an uprising to liberate Lithuania from Soviet occupation.
2002 – An earthquake registering 6.5 M_w struck northwestern Iran, killing at least 261 people and injuring 1,300 others, and later causing widespread public anger at the slow official response.

Leonardo Loredan (d. 1521)
Matthias Vanden Gheyn (d. 1785)
Terttu Savola (b. 1941)

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Today's featured picture

Joseph Simpson (1879–1939) was a British painter, illustrator and etcher. This illustration by Simpson, entitled "Your Motherland Will Never Forget", was published by the Canadian War Records Office in the magazine Canada in Khaki. It depicts a personification of the "Motherland" welcoming back a First World War soldier returning victorious from the front, as suggested by the German helmets on the soldier's backpack. Published in Toronto between 1917 and 1919, the publication described the participation of Canadians in World War I and aimed to raise money for the Canadian War Memorial Fund.

Illustration credit: Joseph Simpson; restored by Adam Cuerden

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