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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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XyRr TIL in 1960 the Mercury-Redstone 1 rocket blasted off and reached an apogee (height) of 4 inches. The rocket also settled back on the launch pad, undamaged, without tipping over.
9JNm TIL ‘Chum’ is actually fish bait, which are usually fish guts, parts, fluid, bones and blood. Which is why in SpongeBob, nobody eats 'Chum’, because they are non-cannibalistic fish. However, Patrick can eat chum because he’s a starfish. Starfish 'feed on dead fish’.
vpK8 TIL Retired NYC subway cars are thrown into the Atlantic Ocean to help create artificial reefs.
LGo9 TIL that Slash hated the song sweet child o mine even though it was an instant hit and was born around a riff he himself played accidentally for fun.
5YadQ TIL about a lady who has(had?) immortal cells. She passed away in 1951 and her cells are still alive today being used in cancer research