eading: The Louisiana Purchase was a landmark event in U.S. history where the country acquired approximately 828,000 square miles of land west of the Mississippi River for $15 million. This deal with France nearly doubled the size of the United States and marked a significant step towards the country's westward expansion. --来自AI解读

eading: The Alaskan boundary dispute was a territorial issue between the United States and Canada that lasted from the late 19th century to the early 20th century. The joint commission established on this day aimed to resolve the border disputes between Alaska and the Canadian provinces of British Columbia and the Yukon. --来自AI解读

eading: Operation Typhoon was a major strategic offensive operation by the German Wehrmacht against the Soviet Union during World War II. The operation aimed to capture Moscow, the capital city of the Soviet Union, but it ultimately failed due to the harsh Russian winter and the Soviet resistance. --来自AI解读

eading: The House Un-American Activities Committee (HUAC) was a committee of the U.S. House of Representatives that was created in 1938 to investigate alleged disloyalty and subversive activities. In 1947, HUAC began investigating the film industry for suspected communist infiltration, leading to the Hollywood blacklist. --来自AI解读

eading: The Shag Harbour UFO incident is one of the most well-known UFO sightings in Canadian history. On October 4, 1967, multiple witnesses reported seeing a large object crash into the waters of Shag Harbour, Nova Scotia. Despite extensive searches, no evidence of the object was found, leading to speculation about extraterrestrial life. --来自AI解读

eading: The Sydney Opera House is a UNESCO World Heritage Site located in Sydney, Australia. It was officially opened by Queen Elizabeth II on October 20, 1973, after 16 years of construction. The building has become an iconic symbol of Australia and is one of the most famous and distinctive buildings of the 20th century. --来自AI解读

eading: The St. Louis Cardinals are a professional baseball team based in St. Louis, Missouri. On October 20, 1982, the Cardinals defeated the Milwaukee Brewers in Game 7 of the World Series, winning the championship title. --来自AI解读

eading: The Oakland Hills fire was a devastating wildfire that occurred in the Oakland Hills area of Oakland, California, on October 20, 1991. The fire resulted in 25 fatalities and destroyed over 3,000 homes and apartments, causing significant damage and displacement. --来自AI解读

eading: Muammar Gaddafi was the de facto leader of Libya from 1969 until his death in 2011. On October 20, 2011, Gaddafi was killed in his hometown of Sirte during the Libyan Civil War. His death marked the end of his 42-year rule over Libya. --来自AI解读