An official message from Earth to aliens is hurling through space. In the ‘70s, a plaque describing Earth was designed by Carl Sagan and Frank Drake so that only a scientifically-educated being who understands hydrogen would be able to translate it. The plaque was put on the Pioneer 10 spacecraft, which hasn’t been in contact with us since 2003 and is now more than 8 billion miles away. Source Source 2 Source 3

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