240 BC: First recorded perihelion passage of Halley’s Comet

1856: The Russian Empire, the Ottoman Empire, Great Britain, France and the Kingdom of Sardinia sign the Treaty

1867: The United States buys Alaska from Russia for $7,200,000 (109 million in 2018 dollars), roughly 2 cents an acre

1870: The 15th Amendment to the US Constitution is adopted, guaranteeing the right to vote regardless of race

1959: Dalai Lama flees China and is granted political asylum in India

1972: Northern Ireland’s government and parliament are dissolved by the British government, and direct rule from Westminster is introduced

2023: Key figures in Artificial Intelligence including Elon Musk and Steve Wozniak sign an open letter warning the race to develop AI systems is out of control and asking for a suspension of at least six months

Source: Onthisday.com