
Planetary-mass object
A planetary-mass object (PMO), planemo,[2] or planetary body is, by geophysical definition of celestial objects, any celestial object massive enough to achieve hydrostatic equilibrium, but not enough to sustain core fusion like a star.[3][4]
Not to be confused with Planet.The purpose of this term is to classify together a broader range of celestial objects than 'planet', since many objects similar in geophysical terms do not conform to conventional expectations for a planet. Planetary-mass objects can be quite diverse in origin and location. They include planets, dwarf planets, planetary-mass satellites and free-floating planets, which may have been ejected from a system (rogue planets) or formed through cloud-collapse rather than accretion (sub-brown dwarfs).
While the term technically includes exoplanets and other objects, it is often used for objects with an uncertain nature or objects that do not fit in one specific class. Cases in which the term is often used: