Why Are Astronomers Much More Interested in the Luminosity of a Star

question 2

Multiple Choice

Why are astronomers much more interested in the luminosity of a star than its apparent brightness?

• A) because luminosity can be measured exactly, but apparent brightness can only be roughly estimated
• B) because the luminosity tells us how bright a star really is, while apparent brightness only tells us how bright it happens to look from Earth
• C) because the luminosity also tells us what elements the star is made of, while apparent brightness cannot tell us a star's chemical make-up
• D) because luminosity can tell us how bright it is inside the star's core, while apparent brightness only tells us about its outside layers
• E) you can't fool me, there is no difference between luminosity and apparent brightness; they are merely different terms for the same property of a star
• Section 17.2: Colors of Stars

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Definitions:

Anxiety

A feeling of worry, nervousness, or unease about something with an uncertain outcome, often reflecting a reaction to stress.

Self-Deception

The process of denying or rationalizing away the relevance, significance, or importance of opposing evidence or logical argument.

Unconscious Conflicts

Internal struggles within the mind that occur without the individual's awareness, often influencing behavior and emotions.

Fixation

An obsessive focus or attachment to an object, concept, or person, often to the exclusion of other considerations.