Laura Churchley left Alice Wackerman and Julie Jenkins speak to commemorate the 50th anniversary of human spaceflight.

In the Rocket Garden at NASA's Kennedy Space Center Visitor Complex in Florida, Laura Churchley (left), Alice Wackerman and Julie Jenkins, daughters of Mercury Astronaut Alan Shepard, speak to the audience in attendance for the United States Postal Service unveiling of two new stamps to commemorate the 50th anniversary of human spaceflight. Listening to them speak is Director of Education and External Relations for Kennedy, Cheryl Hurst (left), Kennedy Center Director, Bob Cabana and United States Postal Service official Steve Massey.

One stamp commemorates NASA's Project Mercury and Alan Shepard's historic launch on May 5, 1961, aboard the spacecraft Freedom 7. The second stamp honors NASA's MESSENGER, which reached Mercury in March to become the first spacecraft to orbit the planet. The two missions frame a remarkable 50-year period in which America advanced space exploration through more than 1,500 crewed and uncrewed flights. Photo credit: NASA/Kim Shiflett