Wikipedia:Main Page history/2015 July 8

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From today's featured article

Radiocarbon dating is used to determine the age of carbon-bearing material by measuring its radiocarbon, the radioactive isotope carbon-14 (with six protons and eight neutrons). Invented by Willard Libby in the late 1940s, the method soon became a standard tool for archaeologists. Radiocarbon is constantly created in the atmosphere, when cosmic rays create free neutrons that hit nitrogen. Plants take in carbon, including radiocarbon, through photosynthesis, and after an animal or plant dies, it stops exchanging carbon with its environment. Half of the radiocarbon decays every 5,730 years; the oldest dates that can be reliably measured by radiocarbon dating are around 50,000 years ago. The proportion of radiocarbon in the atmosphere was reduced starting in the late 19th century by fossil fuels, which contain little detectable radiocarbon, but nuclear weapons testing reversed that trend, almost doubling it by 1963. Accelerator mass spectrometry has become the method of choice for radiocarbon dating; it can be used with samples as small as plant grains. Libby received the Nobel Prize for his work in 1960. (Full article...)

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Did you know...

... that one of the towers of Bissau Cathedral (pictured) is used as a lighthouse to guide ships to the Port of Bissau?
... that Dixi Crosby was the first surgeon in the United States to be sued for medical malpractice?
... that players can ride on dinosaurs in Ark: Survival Evolved?
... that Israeli wrestler Ilana Kratysh won a Grand Prix event despite allegedly being bitten by an Egyptian opponent?
... that the music of L.A. Noire consists of original vocal recordings that reflect the "musical identity" of its 1940s setting?
... that Gordon Ramsay once called Spanish chef Omar Allibhoy the "Antonio Banderas of cooking"?
... that the female sparkling jewelwing damselfly spends about fifteen minutes submerged while laying a batch of eggs?
... that Victoria Price, the daughter of horror icon Vincent Price, is not a fan of horror films?

In the news

In association football, the Women's World Cup concludes with the United States defeating Japan in the final, and the Copa América concludes with Chile defeating Argentina in the final.
Nicholas Winton (pictured), dubbed the "British Schindler" for saving more than 600 children – the majority Jewish – from the Nazis, dies at the age of 106.
More than 140 people are killed when a Lockheed C-130 Hercules crashes into a residential area of Medan, Indonesia.
Hisham Barakat, Egypt's prosecutor general, is assassinated in a car bombing.

Ongoing events:
- Greek debt crisis
Recent deaths:
- Boyd K. Packer
- Val Doonican

On this day...

July 8

1663 – King Charles II of England granted John Clarke the Rhode Island Royal Charter, described by one historian as "the grandest instrument of human liberty ever constructed."
1709 – Great Northern War: Peter I of Russia defeated Charles XII of Sweden in Poltava, effectively ending Sweden's role as a major power in Europe.
1808 – Joseph Bonaparte (pictured) approved the Bayonne Statute, a royal charter intended as the basis for his rule as King of Spain during the Peninsular War.
1947 – After various news agencies reported the capture of a "flying disc" by U.S. Army Air Force personnel in Roswell, New Mexico, the military stated that what was actually recovered was debris from an experimental high-altitude surveillance weather balloon.
2011 – Space Shuttle Atlantis was launched in STS-135, the final mission of the U.S. Space Shuttle program.

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Today's featured picture

Leucanthemum vulgare, popularly known as the ox-eye daisy, is a flowering plant native to the grasslands of Europe and temperate Asia. This flower is often cultivated as an ornamental plant, and in Russia it is the symbol of Peter and Fevronia Day.

Photograph: Derek Ramsey

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