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This Day In History

1979 Nuclear accident at Three Mile Island

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At 4 a.m. on March 28, 1979, the worst accident in the history of the U.S. nuclear power industry begins when a pressure valve in the Unit-2 reactor at Three Mile Island fails to close. Cooling water, contaminated with radiation, drained from the open valve into adjoining buildings, and the core began to dangerously overheat.

The Three Mile Island nuclear power plant was built in 1974 on a sandbar on Pennsylvania’s Susquehanna River, just 10 miles downstream from the state capitol in Harrisburg. In 1978, a second state-of-the-art reactor began operating on Three Mile Island, which was lauded for generating affordable and reliable energy in a time of energy crises.

After the cooling water began to drain out of the broken pressure valve on the morning of March 28, 1979, emergency cooling pumps automatically went into operation. Left alone, these safety devices would have prevented the development of a larger crisis. However, human operators in the control room misread confusing and contradictory readings and shut off the emergency water system. The reactor was also shut down, but residual heat from the fission process was still being released. By early morning, the core had heated to over 4,000 degrees, just 1,000 degrees short of meltdown. In the meltdown scenario, the core melts, and deadly radiation drifts across the countryside, fatally sickening a potentially great number of people.

As the plant operators struggled to understand what had happened, the contaminated water was releasing radioactive gases throughout the plant. The radiation levels, though not immediately life-threatening, were dangerous, and the core cooked further as the contaminated water was contained and precautions were taken to protect the operators. Shortly after 8 a.m., word of the accident leaked to the outside world. The plant’s parent company, Metropolitan Edison, downplayed the crisis and claimed that no radiation had been detected off plant grounds, but the same day inspectors detected slightly increased levels of radiation nearby as a result of the contaminated water leak. Pennsylvania Governor Dick Thornburgh considered calling an evacuation.

Finally, at about 8 p.m., plant operators realized they needed to get water moving through the core again and restarted the pumps. The temperature began to drop, and pressure in the reactor was reduced. The reactor had come within less than an hour of a complete meltdown. More than half the core was destroyed or molten, but it had not broken its protective shell, and no radiation was escaping. The crisis was apparently over.

Two days later, however, on March 30, a bubble of highly flammable hydrogen gas was discovered within the reactor building. The bubble of gas was created two days before when exposed core materials reacted with super-heated steam. On March 28, some of this gas had exploded, releasing a small amount of radiation into the atmosphere. At that time, plant operators had not registered the explosion, which sounded like a ventilation door closing. After the radiation leak was discovered on March 30, residents were advised to stay indoors. Experts were uncertain if the hydrogen bubble would create further meltdown or possibly a giant explosion, and as a precaution Governor Thornburgh advised “pregnant women and pre-school age children to leave the area within a five-mile radius of the Three Mile Island facility until further notice.” This led to the panic the governor had hoped to avoid; within days, more than 100,000 people had fled surrounding towns.

On April 1, President Jimmy Carter arrived at Three Mile Island to inspect the plant. Carter, a trained nuclear engineer, had helped dismantle a damaged Canadian nuclear reactor while serving in the U.S. Navy. His visit achieved its aim of calming local residents and the nation. That afternoon, experts agreed that the hydrogen bubble was not in danger of exploding. Slowly, the hydrogen was bled from the system as the reactor cooled.

At the height of the crisis, plant workers were exposed to unhealthy levels of radiation, but no one outside Three Mile Island had their health adversely affected by the accident. Nonetheless, the incident greatly eroded the public’s faith in nuclear power. The unharmed Unit-1 reactor at Three Mile Island, which was shut down during the crisis, did not resume operation until 1985. Cleanup continued on Unit-2 until 1990, but it was too damaged to be rendered usable again. In the more than two decades since the accident at Three Mile Island, not a single new nuclear power plant has been ordered in the United States.

Courtesy of History.com

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Truman announces development of H-bomb

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U.S. President Harry S. Truman publicly announces his decision to support the development of the hydrogen bomb, a weapon theorized to be hundreds of times more powerful than the atomic bombs dropped on Japan during World War II.

Five months earlier, the United States had lost its nuclear supremacy when the Soviet Union successfully detonated an atomic bomb at their test site in Kazakhstan. Then, several weeks after that, British and U.S. intelligence came to the staggering conclusion that German-born Klaus Fuchs, a top-ranking scientist in the U.S. nuclear program, was a spy for the Soviet Union. These two events, and the fact that the Soviets now knew everything that the Americans did about how to build a hydrogen bomb, led Truman to approve massive funding for the superpower race to complete the world’s first “superbomb,” as he described it in his public announcement on January 31.

On November 1, 1952, the United States successfully detonated “Mike,” the world’s first hydrogen bomb, on the Eniwetok Atoll in the Pacific Marshall Islands. The 10.4-megaton thermonuclear device, built upon the Teller-Ulam principles of staged radiation implosion, instantly vaporized an entire island and left behind a crater more than a mile wide. The incredible explosive force of Mike was also apparent from the sheer magnitude of its mushroom cloud–within 90 seconds the mushroom cloud climbed to 57,000 feet and entered the stratosphere. One minute later, it reached 108,000 feet, eventually stabilizing at a ceiling of 120,000 feet. Half an hour after the test, the mushroom stretched 60 miles across, with the base of the head joining the stem at 45,000 feet.

Three years later, on November 22, 1955, the Soviet Union detonated its first hydrogen bomb on the same principle of radiation implosion. Both superpowers were now in possession of the “hell bomb,” as it was known by many Americans, and the world lived under the threat of thermonuclear war for the first time in history.

Source: https://www.history.com/this-day-in-history/truman-announces-development-of-h-bomb

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Gandhi assassinated

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Mohandas Karamchand Gandhi, the political and spiritual leader of the Indian independence movement, is assassinated in New Delhi by a Hindu extremist.

Born the son of an Indian official in 1869, Gandhi’s Vaishnava mother was deeply religious and early on exposed her son to Jainism, a morally rigorous Indian religion that advocated nonviolence. Gandhi was an unremarkable student but in 1888 was given an opportunity to study law in England. In 1891, he returned to India, but failing to find regular legal work he accepted in 1893 a one-year contract in South Africa.

Settling in Natal, he was subjected to racism and South African laws that restricted the rights of Indian laborers. Gandhi later recalled one such incident, in which he was removed from a first-class railway compartment and thrown off a train, as his moment of truth. From thereon, he decided to fight injustice and defend his rights as an Indian and a man. When his contract expired, he spontaneously decided to remain in South Africa and launched a campaign against legislation that would deprive Indians of the right to vote. He formed the Natal Indian Congress and drew international attention to the plight of Indians in South Africa. In 1906, the Transvaal government sought to further restrict the rights of Indians, and Gandhi organized his first campaign of satyagraha, or mass civil disobedience. After seven years of protest, he negotiated a compromise agreement with the South African government.

In 1914, Gandhi returned to India and lived a life of abstinence and spirituality on the periphery of Indian politics. He supported Britain in the First World War but in 1919 launched a new satyagraha in protest of Britain’s mandatory military draft of Indians. Hundreds of thousands answered his call to protest, and by 1920 he was leader of the Indian movement for independence. He reorganized the Indian National Congress as a political force and launched a massive boycott of British goods, services, and institutions in India. Then, in 1922, he abruptly called off the satyagraha when violence erupted. One month later, he was arrested by the British authorities for sedition, found guilty, and imprisoned.

Source: https://www.history.com/this-day-in-history/gandhi-assassinated

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U.S. Baseball Hall of Fame elects first members

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On January 29, 1936, the U.S. Baseball Hall of Fame elects its first members in Cooperstown, New York: Ty Cobb, Babe Ruth, Honus Wagner, Christy Matthewson and Walter Johnson.

The Hall of Fame actually had its beginnings in 1935, when plans were made to build a museum devoted to baseball and its 100-year history. A private organization based in Cooperstown called the Clark Foundation thought that establishing the Baseball Hall of Fame in their city would help to reinvigorate the area’s Depression-ravaged economy by attracting tourists. To help sell the idea, the foundation advanced the idea that U.S. Civil War hero Abner Doubleday invented baseball in Cooperstown. The story proved to be phony, but baseball officials, eager to capitalize on the marketing and publicity potential of a museum to honor the game’s greats, gave their support to the project anyway.

In preparation for the dedication of the Hall of Fame in 1939—thought by many to be the centennial of baseball—the Baseball Writers’ Association of America chose the five greatest superstars of the game as the first class to be inducted: Ty Cobb was the most productive hitter in history; Babe Ruth was both an ace pitcher and the greatest home-run hitter to play the game; Honus Wagner was a versatile star shortstop and batting champion; Christy Matthewson had more wins than any pitcher in National League history; and Walter Johnson was considered one of the most powerful pitchers to ever have taken the mound.

Today, with approximately 350,000 visitors per year, the Hall of Fame continues to be the hub of all things baseball. 

Source: https://www.history.com/this-day-in-history/u-s-baseball-hall-of-fame-elects-first-members

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