Final answer:
To measure stellar luminosities, we need to consider the mass of the star and the apparent brightness of the star. The inverse square law of light relates these two quantities. By compensating for the dimming effects of distance on light and knowing the distance to the star, we can calculate its luminosity.
Step-by-step explanation:
To measure stellar luminosities, we need to consider two measurable quantities: the mass of the star and the apparent brightness of the star. The law for light that relates these two quantities is the inverse square law of light. According to this law, the apparent brightness of a star decreases with the square of the distance to the star.
We must first compensate for the dimming effects of distance on light in order to measure the luminosities of stars. To do this, we need to know the distance to the star, which is a challenging measurement in astronomy. Once we have the apparent brightness of the star and its distance, we can calculate its luminosity using the inverse square law of light.