If the inclination ($i$) of an unseen companion's orbit is unknown, what does the mass function establish for the companion's heft?

Answer

A minimum estimate ($M ext{sin } i$).

When the inclination is unknown, $ ext{sin } i$ will be less than one, meaning the calculated mass is always a minimum estimate, establishing a boundary condition for the star’s true heft.

If the inclination ($i$) of an unseen companion's orbit is unknown, what does the mass function establish for the companion's heft?
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