Pluto — purchased!

Alan Stern, principal investigator of the New Horizons mission to Pluto, shows off his Pluto — Explored! stamp purchase at the Boulder, CO, Post Office.

The scientist who led last year’s historic mission to Pluto recently paid a special visit to his hometown Post Office.

Alan Stern, principal investigator and leader of the New Horizons mission, dropped by the Boulder, CO, office to purchase the new stamps celebrating the achievement.

“What an honor this was to the more than 2,500 people who worked on this project,” Stern said. “And for me, this is highly satisfying to see my home Post Office carry this stamp.”

Stern purchased the Pluto — Explored! stamps, which USPS issued May 31 to recognize the completion of NASA’s 9-year, 3-billion-mile mission to explore Pluto.

The stamp sheet shows New Horizons, the spacecraft that flew by the dwarf planet last year, as well as an image taken during the probe’s approach.

In July, Stern participated in a ceremony honoring a 1991 Pluto stamp that was affixed to New Horizons during its journey and set a Guinness world record for the farthest distance traveled by a postage stamp.