Frisbee Plastics, the original molder. After learning that he could produce his own disc more cheaply, in 1955 Morrison designed a new model, the Pluto Platter, the archetype of all modern flying discs. He sold the rights to Wham-O on January 23, 1957, and in 1958 Morrison was awarded U.S. Design Patent D183,626 for his product. In June 1957, Wham-O co-founders Richard Knerr and Arthur "Spud" Melin gave the disc the brand name "Frisbee" (pronounced "friz'-bee") after learning that Northeastern college students were calling the Pluto Platter by that term, which derived from the name of the Connecticut-based pie manufacturer, Frisbie
Pluto throughout the 20th century. Astronomers initially calculated its mass based on its presumed effect on Neptune and Uranus. In 1931, Pluto was calculated to be roughly the mass of Earth, with further calculations in 1948 bringing the mass down to roughly that of Mars. In 1976, Dale Cruikshank, Carl Pilcher and David Morrison of the University of Hawaii calculated Pluto's albedo for the first time, finding that it matched that for methane ice; this meant Pluto had to be exceptionally luminous for its size and therefore could not be more than 1 percent the mass of Earth. (Pluto's albedo is