On February 18, 1930, a young astronomer named Clyde Tombaugh made history when he discovered Pluto at the Lowell Observatory in Arizona. At just 24 years old, his breakthrough revealed an entirely new celestial body beyond Neptune, expanding our understanding of the solar system’s outer reaches. His painstaking research, which involved studying millions of star images, was a monumental achievement that laid the foundation for further exploration of the Kuiper Belt—a distant region filled with icy objects, of which Pluto remains the most well-known.

A Historic Space Mission

Fast forward to 2006, nearly a decade after Tombaugh’s passing in 1997, when NASA launched the New Horizons probe. This spacecraft embarked on an ambitious nine-year journey to Pluto, carrying a unique tribute—a small container holding Tombaugh’s ashes. In July 2015, the probe completed its historic flyby, passing within 7,800 miles (12,500 kilometers) of Pluto’s surface, making it the closest approach ever by a spacecraft.

A Fitting Tribute to an Astronomical Pioneer