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.

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

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