It would be fitting I think if aliens found his ashes considering he's was something of an ET evangelist and eventually claimed some of his mysterious sightings (green fireballs and glowing rectangles moving in unnatural ways) were probably of ET origin and its unscientific to dismiss this out of hand. Wiki:
Although our own solar system is believed to support no other life than on Earth, other stars in the galaxy may have hundreds of thousands of habitable worlds. Races on these worlds may have been able to utilize the tremendous amounts of power required to bridge the space between the stars..." Tombaugh stated that he had observed celestial phenomena which he could not explain, but had seen none personally since 1951 or 1952. "These things, which do appear to be directed, are unlike any other phenomena I ever observed. Their apparent lack of obedience to the ordinary laws of celestial motion gives credence."
Although our own solar system is believed to support no other life than on Earth, other stars in the galaxy may have hundreds of thousands of habitable worlds. Races on these worlds may have been able to utilize the tremendous amounts of power required to bridge the space between the stars..." Tombaugh stated that he had observed celestial phenomena which he could not explain, but had seen none personally since 1951 or 1952. "These things, which do appear to be directed, are unlike any other phenomena I ever observed. Their apparent lack of obedience to the ordinary laws of celestial motion gives credence."
https://en.wikipedia.org/wiki/Clyde_Tombaugh#Interest_in_UFO...