To calculate the masses of stars in a binary system, we must measure their ________.

Question

Quizplus · Accepted Answer

By measuring the stars' orbital period and average orbital distance, we can use Kepler's Laws to calculate the combined mass of the binary system. Once we know the combined mass and can measure the individual stars' velocities and positions within the system, we can use those measurements to determine the masses of each individual star. Spectral types, absolute magnitudes, and luminosities can provide additional information about the stars, but are not sufficient on their own to calculate their masses in a binary system. Distance from Earth is also helpful for determining various properties of stars, but not directly related to calculating binary star masses.

To Calculate the Masses of Stars in a Binary System