There is a 600 year old 240 paged book called the Voynich Manuscript, that’s written language is still completely unknown today.
15
Since 1982, a radio frequency emanating from Russia has been broadcasting a buzzer-like sound and, periodically, an unknown voice reads orders, names, and numbers. No one knows where exactly it is coming from or what it means.
13
There are pictures of Knights fighting Snails in old Medieval manuscripts - and nobody knows why.
23
There is a mysterious and loud radio signal known as 'the space roar' that has yet to be explained.
15
In 1958, a nuclear bomb was lost somewhere along the swampy coast of Georgia. Its whereabouts remain a mystery to this day.
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