MOUNTAIN VIEW, Calif. -- Not describing Pluto as a planet is being viewed like the solar system snub of the century. The ninth wonder of the worlds, distant Pluto, has lost favor as a planet worth counting on.

Thats the belief of Neil de Grasse Tyson, director of the Hayden Planetarium in New York City.

Tyson supports the planetariums exhibit that ranks Pluto as belonging to the Kuiper Belt of icy objects past Pluto and has given a thumbs-down vote on exalting the way-out world as the solar systems ninth planet.

The 411 on Pluto

Pluto: the dark world. Visit SPACE.com"s reference section for interesting facts about the planets in other objects in our solar system and other fascinating subjects. Overview of Pluto Images and Maps of Pluto and its Moon Charon

Climate and structure Moons and Ring

Historical Notes Exploration

"Its mostly a specious discussion," said Dale Cruikshank, a NASA research scientist in the astrophysics branch and specializing in small bodies and the Kuiper Belt.

Cruikshank is also president of the International Astronomical Unions (IAU) commission for the physical study of the planets and satellites in the solar system. The commissions official position is that Pluto is one of the nine planets in the solar system, a status that the faraway object has held since it was discovered in 1930, he said.

The late astronomer, Clyde Tombaugh, first spotted Pluto, the only planet ever to be discovered by an American, and the only planet found that added to the growth of our solar system in the 20th century.

"Pluto has many attributes which suggest it should be called a planet. It has its own moon, for example. It has an atmosphere. It has a surface that interacts and changes with the atmosphere. Like Neptunes moon, Triton, Pluto probably has a haze in the atmosphere. For all we know it has clouds," Cruikshank said.