Look up planetary in Wiktionary, the free dictionary. Planetary means relating to a planet or planets. It can also refer to: Planetary habitability, the...

A planetary system is a set of gravitationally bound non-stellar objects in or out of orbit around a star or star system. Generally speaking, systems...

A planetary nebula is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives...

Planetary habitability is the measure of a planet's or a natural satellite's potential to develop and maintain environments hospitable to life. Life may...

Planetary science (or more rarely, planetology) is the scientific study of planets (including Earth), celestial bodies (such as moons, asteroids, comets)...

Planetary romance (other synonyms are sword and planet, and (inter)planetary adventure) is a subgenre of science fiction or science fantasy in which the...

Planetary Annihilation is a real-time strategy PC game originally developed by Uber Entertainment, whose staff included several video game industry veterans...

An epicyclic gear train (also known as a planetary gearset) is a gear reduction assembly consisting of two gears mounted so that the center of one gear...

A planetary core consists of the innermost layers of a planet. Cores may be entirely liquid, or a mixture of solid and liquid layers as is the case in...

Planetary boundaries are a framework to describe limits to the impacts of human activities on the Earth system. Beyond these limits, the environment may...