Wham-O called their new product the Hula Hoop. (The name had been used since the 18th century, but till then had not been registered as a trademark.) The Hula-Hoop became the biggest toy fad in modern history. Twenty-five million were sold in four months, and in two years sales reached more than 100 million. "Hula Hoop mania" continued through the end of 1959, and netted Wham-O US$45 million (US$346M adjusted for inflation to 2012). Shortly thereafter, the company had another huge success with the Frisbee. In 1955, inventor Fred Morrison began marketing a plastic flying disc called the Pluto Platter. He
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