The star Vega has an apparent visual magnitude of 0.03 and the star HR 4374 has an apparent visual magnitude of 4.87.It has been determined that both stars are at the same distance from the Earth.What does this information tell us about the two stars?
A)Together the two stars would have a magnitude of 4.9.
B)Vega must produce less energy per second than HR 4374.
C)Vega must produce more energy per second than HR 4374.
D)Vega will appear fainter to us than HR 4374.

Question

Quizplus · Accepted Answer

Apparent visual magnitude is related to the energy output of a star. A lower magnitude indicates a brighter star, which means it is producing more energy per second. Since Vega has a lower magnitude than HR 4374 despite being at the same distance from Earth, it must be producing more energy per second. Therefore, option C is correct. Option A is incorrect because the combined magnitude of two stars cannot be simply added together. Option B is incorrect because we do not know the energy output of HR 4374. Option D is incorrect because Vega actually has a lower magnitude (and therefore appears brighter) than HR 4374.

The Star Vega Has an Apparent Visual Magnitude of 0