A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk.
In the Solar System
For a list of geophysical planets in the Solar System, see: List of gravitationally rounded objects of the Solar System This also includes a list of the eight planets according to the IAU definition. For a list of objects in the Solar System once but no longer generally considered planets, see: List of former planets For a list of objects in the Solar System, including planets, that have been or are believed to exist, but either have not been proven or have been disproven, see: List of hypothetical Solar System objects
Outside the Solar System
Exoplanets
List of nearest exoplanets
List of proper names of exoplanets
Extrasolar systems
List of multiplanetary systems
List of exoplanets discovered using the Kepler space telescope
List of stars with proplyds
List of rogue planets
Exoplanets by method of detection
List of exoplanets detected by radial velocity
List of transiting exoplanets
List of exoplanets detected by microlensing
List of directly imaged exoplanets
List of exoplanets detected by timing
Records in exoplanet detection
List of exoplanet extremes
List of exoplanet firsts
Potential terrestrial exoplanets
List of nearest terrestrial exoplanet candidates
List of potentially habitable exoplanets
Fictional or non-scientific planets
For a list of planets as used in astrology, see: Planets in astrology
For a list of supposed planets not based on scientific evidence, see: Planetary objects proposed in religion, astrology, ufology and pseudoscience For a list of planets in fiction, see: Planets in science fiction, Stars and planetary systems in fiction and Fictional planets of the Solar System
Mixed
List of planet types (etymologically accepting of multiple categories)