planet x is unknown but is farther than Pluto
The Mystery of the Third Planet was created in 1981.
The duration of The Mystery of the Third Planet is 3000.0 seconds.
The cast of Mystery of the Third Planet - 1987 includes: Glenn Stanton as Background
Pluto By Alicia
Pluto By Alicia
The mystery planet refers to the hypothetical ninth planet in our solar system, sometimes referred to as Planet Nine or Planet X. It has not yet been directly observed but is believed to exist based on its gravitational effects on other objects in the Kuiper Belt.
It is called the mystery planet because it is so far away, and we don't really know anything about it because we are unable to visit it.
Space Patrol - 1950 The Mystery of Planet X 3-35 was released on: USA: 29 August 1953
Stories from My Childhood - 1998 Alice and the Mystery of the Third Planet 1-3 was released on: USA: 1998
Mystery Science Theater 3000 - 1988 Being from Another Planet 5-5 was released on: USA: 4 July 1992
Mystery Science Theater 3000 - 1988 Women of the Prehistoric Planet 2-13 was released on: USA: 20 February 1990
no Pluto is fully studied and there are no mysteries but there are planets beyond Pluto