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TIL Refracting telescopes use the original telescope design by Galileo, with two lenses in a hollow tube. They can provide a crystal clear image for observing close celestial objects like moon and planets but not good for for deep sky objects, unlike reflector telescopes

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KYQk9 TIL Abram Petrovich Gannibal began the first Black Russian aristocratic dynasty in the 1700s. Born in what is now Cameroon, Central Africa - and brought to the court of Peter The Great - he became a war General and godson of the Emperor. Many European royal houses descend from Gannibal today...
5YplB TIL that in 1945 six Americans, five of which were children, were killed in Oregon by a Japanese bomb that was delivered via balloon. They were the only citizens to die by enemy weapon on the American mainland during World War II.
BgJXK TIL that unescorted women prevented men from casually assaulting them in the early 1900s with a simple clothing accessory - the hat pin, and it was so effective as a weapon that laws were passed limiting it's length in many states.
Lggd TIL that blue M&M food dye reduces paralysis from secondary spinal injuries, such as swelling around the spinal cord and the effects of chemical surges around the the injury which kills off healthy and uninjured cells. The only notable side effect - it will turn you blue temporarily.
4MKo TIL that Franklin Roosevelt was the first sitting US president to ride aboard an airplane, over 40 years after its invention.