How Have Astronomers Measured the Mass of the Black Hole

question 57

Multiple Choice

How have astronomers measured the mass of the black hole at the center of our galaxy?

• A) Using the rotation curve derived from 21-cm emission
• B) By observing the motions of stars near the center of the galaxy
• C) By measuring the brightness of the quasar
• D) By measuring the Doppler shift of Sagittarius A*

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Definitions:

Physical Height

The measurement of an individual from the base of the feet to the top of the head when standing upright.

Peer Popularity

the degree to which an individual is liked or accepted by their peer group.

Causal Impact

entails the effect that one variable has on another, establishing a cause-and-effect relationship between the two.

Observable Evidence

Information or data that can be perceived or noticed using the senses or scientific instruments.