Johndale Solem origin of the shape of rubble-pile asteroids. His analytic theory of the breakup of comets by planetary tidal forces resulted in his calculation of the diameter and density of the parent comet of Shoemaker-Levy 9 as it was before breaking up in the tidal field of Jupiter in 1994 (1994a). Solem's research on interplanetary travel culminated in his MEDUSA concept, a nuclear explosive propelled spacecraft for interplanetary space travel (1994b). Gregory Matloff said this was "a surprising [propulsion] concept which might greatly reduce spacecraft mass." The concept inspired research and elaboration by the aerospace community. At the behest of NASA's
Carolyn S. Shoemaker Rittenhouse Medal of the Rittenhouse Astronomical Society in 1988 and the Scientist of the Year Award in 1995. The Hildian asteroid 4446 Carolyn, discovered by college Edward Bowell at Lowell Observatory in 1985, was named in her honor. Carolyn Shoemaker is credited by the Minor Planet Center with the discovery of 377 numbered minor planets made between 1980 and 1994. Carolyn S. Shoemaker Carolyn Jean Spellmann Shoemaker (born June 24, 1929) is an American astronomer and is a co-discoverer of Comet Shoemaker–Levy 9. She once held the record for most comets discovered by an individual. Carolyn Jean Spellmann was born