When using standard astronomical units ($P$ in years, $a$ in AU), what quantity does the equation $(M_1 + M_2) = a^3 / P^2$ yield directly?
Answer
The sum of the masses of the two stars
This specific formulation of the law, where the constant of proportionality $G$ conveniently cancels out, yields the total mass of the system, $M_1 + M_2$.
Frequently Asked Questions
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