Memorial

Explanation: A small container of Clyde Tombaugh's ashes is affixed to the inside, upper deck of the spacecraft, with the inscription: "Interned herein are remains of American Clyde W. Tombaugh, discoverer of Pluto and the solar system's 'third zone', Adelle and Muron's boy, Patricia's husband, Annette and Alden's father, astronomer, teacher, punster, and friend: Clyde W. Tombaugh (1906-1997)."

Pluto

Image credit: NASA/Parman's Page.