What is the only way to measure directly the mass of a star accurately?
A) Measure its distance using trigonometric parallax and its brightness using photometry.
B) It is not possible to measure the mass of a star.
C) Measure its spectral type and luminosity class, then use the H-R diagram.
D) Measure its gravitational effect on another object.

Question

Quizplus · Accepted Answer

The mass of a star can be directly measured by observing its gravitational effect on another object, such as in a binary star system where the masses of the stars can be determined from their orbital motions.

What Is the Only Way to Measure Directly the Mass