Which one of these is NOT needed to compute a distance to a star by the spectroscopic parallax method?
A) the mathematical relationship among distance, absolute magnitude, and apparent magnitude
B) the star's stellar parallax
C) the star's apparent magnitude
D) the star's luminosity

Question

Quizplus · Accepted Answer

Spectroscopic parallax does not require the star's stellar parallax. Instead, it uses the star's apparent magnitude, its spectral type (to estimate luminosity and hence absolute magnitude), and the relationship between distance, absolute magnitude, and apparent magnitude to calculate distance.

Which One of These Is NOT Needed to Compute a Distance