How would astronomers measure the velocity of the star shown in the figure below?
A) through its spectrum
B) through a transit
C) through its angular velocity across the sky
D) through its brightening or dimming with time

Question

How would astronomers measure the velocity of the star shown in the figure below? 
A) through its spectrum 
B) through a transit 
C) through its angular velocity across the sky 
D) through its brightening or dimming with time

Quizplus · Accepted Answer

Astronomers would measure the velocity of the star shown in the figure through its spectrum. This can be done by analyzing the Doppler shift of the star's spectral lines, which will reveal whether the star is moving towards or away from Earth and at what speed.

How Would Astronomers Measure the Velocity of the Star Shown