NASA is celebrating the 50th anniversary of Shepard's trip into space, when he became the first American (and second human) to reach outer space.

As part of the celebration, the space agency unveiled two stamps, with one featuring images of Shepard, the Freedom 7 capsule and the historic launch. The other shows NASA's Messenger probe, which recently reached Mercury to become the first spacecraft to orbit the planet. NASA also plans on recreating Shepard's flight and recovery, as well as a tribute to his contributions as a moonwalker on the Apollo 14 lunar mission.

The mission, dubbed Mercury-Redstone 3, only lasted 15 minutes and 28 seconds -- a blip in comparison to today's 15-day missions. Still, it set an everlasting precedent  and helped set up multiple generations of space exploration.

Here is a look back in photos of Shepard, his first trip into space and his legacy.

For more on Shepard's trip into space, check out NASA Celebrates America's Space Shepard.

Follow Gabriel Perna on Twitter at @GabrielSPerna