The US exploded the world's first hydrogen bomb. (1952) The bomb, called Mike, was the first in a series of two test explosions, called Operation Ivy. The tests were performed in the Pacific Ocean at the Marshall Islands. Mike had a force of more than 10 megatons, 500 times more powerful than the nuclear bomb the US dropped on Nagasaki on August 9, 1945. The second bomb, called King, was the world's biggest pure-fission bomb and was exploded on November 16.
Puerto Rican nationalists attempted to assassinate US President Truman. (1950) Oscar Collazo and Griselio Torresola tried to attack the President while he was residing at the Blair House while the White House underwent renovations. The two assailants were able to walk right up to the front door and open fire. The President and his wife were upstairs and were not harmed. Torresola was killed by the US secret service during the unsuccessful attack, and Collazo was sentenced to life in prison after President Truman commuted his death sentence.
Michelangelo's Sistine Chapel ceiling fresco was opened for public exhibition for the first time. (1512) Michelangelo painted scenes from the Bible's Genesis on the chapel's ceiling. He later painted an altar wall with The Last Judgement as well. The works became some of the most influential and well-known in Western art history. The ceiling alone took him nearly four years to finish.
More than 6,000 US soldiers were involuntarily exposed to the radioactive fallout of a series of atomic explosions. (1951)Desert Rock was a series of three atomic explosion training missions, which were part of Operation Buster-Jangle. The explosion tests were carried out in Nevada, utilizing 6,500 US troops.
The Detroit-Windsor Tunnel was dedicated. (1930) US President Herbert Hoover marked the opening of the tunnel by turning a "golden key" at the White House. The 5,160-foot (about 1,573-meter) tunnel connects Detroit, Michigan, to Windsor, Ontario in Canada. It now is the second-busiest international border crossing between Canada and the US.
US President John Adams became the first US leader to live in the White House. (1800) President Adams moved into the Executive Mansion, which later was called the White House. Construction began on the White House in 1792, and it took eight years to complete.
The Maastricht Treaty went into effect, creating the European Union. (1993) The treaty not only unified the European countries politically, but also economically. The treaty included plans to create the "euro," an official currency that would be shared by all member countries. The euro first became an official currency on January 1, 1999.
The US Coast Guard was put under the control of the US Navy during peacetime. (1941) US President Franklin D. Roosevelt's reallocation of the US Coast Guard forces was a strong indication of US intentions to join World War II. The US Coast guard, at that time, reported to the Department of Treasury during peacetime and the US Navy during wartime. The Coast Guard now reports to the office of Homeland Security during peacetime and continues to report to the Navy during times of war.
The US Weather Bureau, now known as the National Weather Service, gave its first forecast. (1870) Initially, the bureau reported to the US Secretary of War, but later would report to the Department of Commerce as part of the National Oceanic and Atmospheric Administration (NOAA).
The world's first female medical school opened. (1848) The Boston Female Medical School ultimately became part of the Boston University School of Medicine. It was the first university in the world to offer formal medical training to women.
The Mackinac Bridge in Northern Michigan opened as the world's longest suspension bridge. (1957) The bridge, which spans 26,372 feet (about 8,038 meters) was considered the longest "between anchorages" — if measured between towers, the Golden Gate Bridge in San Francisco would still have held the record. Both bridges have long since been surpassed in span length, regardless of how they're measured.
The world's largest radio telescope was first used at the Arecibo Observatory in Puerto Rico, which opened on this day. (1963) The telescope is used to collect data from space probes and satellites. The telescope, the world's biggest single-aperture telescope, is operated by Cornell University and the US National Science Foundation.