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The classification substellar object (or substar) covers objects that are like stars except they have less mass, specifically, insufficient mass to trigger hydrogen burning, which is below about 0.08 solar masses. The classification covers brown dwarfs and similarly-large giant planets, and is used whether or not these objects are within star systems, and also regardless of formation: the term may be used for "former stars" (i.e., beyond their main sequence) if they are reduced to that small mass. A common use of the term is for a detected object that apparently lacks the size or mass to indicate a star, but for which not enough characteristics have been determined to distinguish between a planet versus a brown dwarf.