In class, we derived an expression for the lifetime of a main sequence star assuming only...
In class, we derived an expression for the lifetime of a main sequence star assuming only 10% of the mass can be used as fuel.
However, for stars less massive than about 0.5 solar masses, the star is fully convective, and 100% of the mass can be used as fuel, which increases the lifetime by a factor of 10.
Use this information and the original lifetime formula to estimate the lifetime of a 0.1 solar mass star. Express your answer in units of billions of years (Gyr).
Note that the Universe is about 14 billion years old.
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In class, we derived an expression for the lifetime of a main
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