In 2006, NASA placed a 1991 postage stamp inside the New Horizons spacecraft before sending it off to explore the outer reaches of the solar system. Yes, despite the cost of international shipping, 29 cents can get your stamp all the way to Pluto.

That “Pluto: Not Yet Explored” stamp officially became the world’s farthest-traveling stamp when New Horizons flew by the dwarf planet nine and a half years later, zooming 3 billion miles away from Earth, according to Guinness World Records—not that there were a whole lot of candidates. 

USPS

A year later, to honor the occasion, the U.S. Postal Service has created two new stamps (seen above) featuring New Horizons and the dwarf planet.

Just in case someone was gearing up to try to break the New Horizon-carried stamp’s record, know that it’s got a long head start. The spacecraft is headed even farther into the solar system to study the Kuiper Belt, the region beyond Neptune.

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