Wikipedia:Selected anniversaries/January 11
- 1787 – German-born British astronomer and composer William Herschel (pictured) discovered the Uranian moons Oberon and Titania. They were later named by his son John after the King and the Queen of the Faeries from William Shakespeare's play A Midsummer Night's Dream, respectively.
- 1922 – Insulin was first administered to a human patient with diabetes at the Toronto General Hospital in Toronto, Canada.
- 1923 – Troops from France and Belgium invaded the Ruhr Area to force the German Weimar Republic to pay its reparation payments in the aftermath of World War I.
- 1964 – In a landmark report, U.S. Surgeon General Luther Leonidas Terry issued the warning that smoking may be hazardous for one's health, concluding that it has a causative role in lung cancer, chronic bronchitis, emphysema, and other illnesses.
- 1986 – The Gateway Bridge in Brisbane, Australia, at the time the longest prestressed concrete free cantilever bridge in the world, opened.
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