Two Stars Both Have Parallaxes of 0

question 5

Multiple Choice

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 is both 100× brighter and larger than star B.
• B) Star B must be ten times more luminous.
• C) Star A must be ten times closer.
• D) Star A is both 100× brighter and more luminous than star B.
• E) Nothing, since we do not know their absolute magnitudes.

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Definitions:

NLF Fighters

Refers to guerrilla fighters from the National Liberation Front, primarily during the Vietnam War, fighting against South Vietnamese and United States forces.

US Troops

Military forces of the United States, including the Army, Navy, Air Force, Marines, and Coast Guard.

European Allies

Countries in Europe that are allied or partnered with each other, often referring to alliances formed during major conflicts such as World War I or World War II.

Vietnamese War

Also known as the Vietnam War, a prolonged conflict from 1955 to 1975 between communist North Vietnam, supported by its allies, and South Vietnam, backed by the United States.