Planet X (disambiguation)

Planet X may refer to:

Astronomy

 * Planet X, a disproved hypothetical planet proposed in 1906 by Percival Lowell to have existed beyond the planet Neptune.
 * Colloquially, and by extension, any hypothetical trans-Neptunian planet, in particular Planet Nine.

Science fiction

 * Planet X, the home planet of Marvel Comics character Groot and other flora colossi
 * "Planet X" (comics), a 2004 X-Men comic book story-line
 * Planet X (Star Trek), a 1998 novel depicting a crossover between The X-Men and Star Trek
 * The name for several fictional planets of the Solar System
 * The planet Daffy Duck seeks in the 1953 Merrie Melodies cartoon Duck Dodgers in the 24½th Century
 * The home planet of the Xiliens, a fictional alien race featured in the 1965 kaiju film Invasion of Astro-Monster
 * A planet in David Ossman's 1973 sci-fi comedy album How Time Flys

Music

 * Planet X (Derek Sherinian album), 1999
 * Planet X (Helios Creed album), 1994
 * Planet-X, an album by bassist Jimmy Johnson
 * Planet X (band), a progressive metal band founded by Derek Sherinian
 * Plan-It-X Records, a DIY punk rocks record label

Other uses

 * Nibiru cataclysm, a supposed impending disastrous encounter between Earth and a large astronomical object
 * Operation Planet X, a military operation during the Iraq War in 2003
 * Packages from Planet X, a 2013-14 animated television series created by Jeff Harter and aired on Teletoon
 * Planet X Limited, a British bicycle company
 * Planet X Television, an action sports TV show