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"Pluto Not Yet Explored" Stamp Affixed to the New Horizons Spacecraft
Release Date: July 20, 2016
A 1991 "Pluto Not Yet Explored" stamp was affixed to the New Horizons spacecraft shortly before launch from Cape Canaveral, Florida in 2006. On July 19 the stamp was recognized by Guinness World Records for the farthest distance traveled by a postage stamp, going more than 3.2 billion miles to Pluto and beyond.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory