Fifth planet
Fifth planet may refer to:
- Jupiter, the fifth planet from the Sun in the Solar system
- Fifth planet (hypothetical), any of various hypothetical planets thought to have existed
- Fifth Planet, a science fiction novel by Fred and Geoffrey Hoyle
- Planet V, a scientific proposal in 2002 for destroyed fifth planet
- Mars, the fifth planet from Earth in the Ptolemaic geocentric model
- Ceres (dwarf planet), the dwarf planet orbiting between Mars and Jupiter
See also