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Question
Two stars both have parallaxes of 0.023", but star A has apparent magnitude +2.3, while star B is magnitude +7.3. Which statement is true?A) Star A must be ten times closer.
B) Star B must be ten times more luminous.
C) Nothing, since we do not know their absolute magnitudes.
D) Star A is both 100 brighter and more luminous than star B.
E) Star A is both 100 brighter and larger than star B.
Answer
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