› added 6 years ago

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TIL that we've tiny mirrors (retroreflectors) on the moon to reflect the laser beams fired from earth to measure the lunar distance. The round-trip takes of about 2.5 seconds and the distance to the Moon can be measured with millimeter precision.

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N7WpQ TIL that Al-Qaeda were surprised by the collapse of the Twin Towers. Among those planning the attacks, Osama Bin Laden had been the most "optimistic", due to his experience in engineering, and had predicted that the fire would collapse the area where the planes hit and all the floors above only
0wE0A TIL Sindberg is virtually unknown in his home country of Denmark but considered a folk hero in China where he is estimated to have saved 20.000 during the Nanjing massacre. Armed only with the Danish flag he held off the Japanese from entering the makeshift shelter he set up in a cement factory.
GYNME TIL about Monte Melkonian, an American citizen, who joined the Nagorno-Karabakh war in the early 90’s. With little military experience he rose to the rank of Lieutenant Colonel in command of 4 thousand men. He is recognized as a hero in Armenia with statues standing today in his honor.
neNPB TIL when you die in Super Mario Bros. you can hold down the A button while you hit Start to continue from the the world where you left off.
Egx1X TIL "1" wasn't considered a number by Ancient Greeks (even Aristotle & Euclid). Numbers were multitudes of units (1 was the unit). "One is the seed of number but not number." This view didn't change til 1701 AD, when 1 was defined as a number in the first math dictionary: "Mathematicks Made Easie"