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In astronomy, a star’s initial mass determines its ultimate outcome in life. Unless, that is, a stellar companion alters the deal.
When isolated stars form, their fates are pre-determined.
Stellar lifespans rely primarily on initial mass and heavy element content.
Below 7.5% of the Sun’s mass, you’re only a failed star: a brown dwarf.
Above that but below 0.4 solar masses, you’re a red dwarf.
Fully convective, its ultimate fate is a helium white dwarf.