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TIL At age 24, George Ellery Hale revolutionized solar observations with his invention of the spectroheliograph, making it possible to photograph the sun's prominences in full daylight. A spectroheliograph can tune-in to gases such as hydrogen and calcium, and photograph specific solar details

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rN5v1 TIL Medieval Benin City was described as "wealthy and industrious" and was said to have walls 4x the size of The Great Walls of China
YpRoW TIL that the magnetc field of Earth orients iron-rich minerals in molten lava along the field lines, then becomes locked into place as the lava hardens. By studying different layers of solidified lava, we know that magnetic poles fliped in the past and will do it again.
rRQXM TIL that weapons manufacturer Remington produces an 8-gauge shotgun called the Master Blaster. It's classified as an "industrial tool" rather than a firearm, being used to blast away built-up materials within rotary kilns from a distance.
rdxe TIL in August 2001 actor James Woods reported 4 suspicious individuals on his flight. Authorities did not act on his claim and they later turned out to be the 9/11 hijackers.
VKkk TIL that the French each have a single card that holds their entire medical record going back to 1998, which can be scanned wherever they need medical attention