› added 13 years ago

108

TIL Just after WWII, multiple short wave radio stations located around the world appeared. These stations transmit letters and numbers, presumably to spies and still operate today.

Read more wikipedia.org

via reddit.com

wogY8 TIL about Ultrasonic cross-device tracking. Audio "beacons" can be embedded into television advertisements. In a similar manner to radio beacons, these can be picked up by smartphones, which allows the behavior of users to be tracked. Humans can't hear these sounds at all.
7reDx TIL A WW2 pigeon named Mary of Exeter survived an assassination attempt by a German warhawk, was shot, hit with shrapnel, and survived a bombing of her loft while delivering messages across the English Channel to France.
b9QVE TIL that most of Sam Jones' lines in Flash Gordon were dubbed by another (unknown?) actor, after quitting before the movie was finished and that George Lucas had originally wanted to make it, but went to to film Star Wars instead, which also had a famously (deliberately, this time) dubbed actor. #20
4XLeb TIL the Haskell Free Library is the only library to operate in 2 countries on the US/Canada border. It has 2 entrances, one on each country and is a transnational space where citizens from both countries can enter without a passport.
gMwdL TIL that after the Apollo 11 moonwalk, NASA was concerned about the volatility and possible fire or explosion of lunar dust after the LM was filled with oxygen. Armstrong and Aldwin spread out a sample in the LM before repressurizing and watched to see if it caught fire or smoldered. It did not.