In the 1960s, the US launched a group of satellites to monitor international compliance with a treaty prohibiting all tests of nuclear weapons except those conducted underground. In 1979, one of the satellites detected an unidentified double flash characteristic of an atmospheric nuclear explosion. The data were initially interpreted as evidence of a South African nuclear test, but experts later determined that the flash was likely not nuclear in origin and may have instead been caused by what? Discuss
Source: The Free Dictionary
Aizu was once the sturdiest castle in northeast Japan, but it was destroyed in a 
Valachi, a New York gangster, was the first Mafia member to publicly acknowledge the organization’s existence. A “soldier” in New York City’s powerful Genovese crime family, he testified before a congressional committee on organized crime in 1963, disclosing details about the Mafia’s history and operations and making “Cosa Nostra” a household name. Three years later, he attempted suicide in his prison cell but survived. Why did Vito Genovese put out a $100,000 contract on Valachi in 1962? 
In 1964, Prometheus, a Great Basin Bristlecone Pine, was the oldest known non-clonal organism on Earth. That year, a graduate student cut down the 5,000- year-old tree to examine its ring growth patterns and derive information about the climate. It is unclear who suggested that Prometheus be cut down, why the action was deemed necessary, and whether its impact was fully understood at the time. Methuselah is currently the oldest known living tree. How old is it? 
On September 21, 1995, news spread around the world that Hindu worshippers in India and several other countries were experiencing what they considered a miracle. At numerous temples, thousands of Hindus were spooning offerings of milk to statutes of deities, especially the elephant-headed god Ganesha, and claiming that the milk—which appeared to disappear from the spoons—was being miraculously consumed by the gods. What scientific explanation was given for the phenomenon? 
On September 21, 1981, 
Maurice Barrymore was the first in the famous family of Barrymore actors. In 1875, a few years after he began his acting career in London, Barrymore went to New York and became an instant success. Over the next 25 years, he starred in a variety of roles. In 1876, he married Georgiana Drew, the actress daughter of famous British-American actors John and Louisa Lane Drew, thus founding what would become known as “The Royal Family of Broadway.” Who are the other famous Barrymore actors? 
An o-ring is a rubber ring that is used in machinery as a seal against substances like oil and air. Although it is one of the most commonly used seals, it is forever linked to a catastrophic failure. After the space shuttle Challenger exploded in 1986, investigators determined that the o-ring seal in one of the shuttle’s solid fuel rockets failed due to a loss of elasticity that resulted from the low temperature at launch time. How was this problem later demonstrated at a news conference?