NASA's New Horizons probe officially entered Pluto's sphere of gravitational influence last week, and this Tuesday, more than nine years after leaving Earth, the spacecraft will perform a flyby of the icy dwarf planet at a distance of 7,800 miles. Onboard instruments will capture the most detailed images of Pluto ever seen, but nestled next to these tools are some more unusual items of cargo — including a portion of the ashes of Clyde Tombaugh, the American astronomer who discovered Pluto.
Tombaugh, who died in 1997, has a pretty remarkable story, as this NASA interview with his children Annette and Alden reveals. He started life as farmer, making his own telescopes from scraps of agricultural equipment, and in his early 20s he got in touch with the Lowell Observatory to get some feedback on his work.
"He wanted them to give him suggestions to build better telescopes and so he sent them some of his drawings of Mars and Jupiter," said Annette Tombaugh. "They wrote back that they would like to hire him." Tombaugh's work at the observatory eventually led to his discovery of Pluto in 1930 as well as hundreds of other asteroids.
A small container holding some of Tombaugh's ashes are fixed to the inside upper deck of New Horizons, bearing 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)."
Some of the other mementos onboard the probe include a CD with images of staff who worked on the project, a small piece of SpaceShipOne (the craft that completed the first manned private spaceflight in 2004), a pair of state quarters from Florida and Maryland (where the probe was launched and built respectively), and a 1991 US stamp of the dwarf planet bearing the motto: "Pluto: Not Yet Explored."
"I think my dad would be thrilled with the New Horizons, I mean who wouldn’t be?" Annette Tombaugh told NASA. "When he looked at Pluto it was just a speck of light... I’m sure that to have the planet you discovered better defined, better understood. It would have meant so much to him."