A 3 solar mass main sequence star is at a larger distance than a 0.4 solar mass main sequence star. Which star appears brighter?

A. The 3 solar mass main sequence star.
B. We cannot tell with the information given.
C. The 0.4 solar mass main sequence star.
D. The stars are approximately the same brightness.
E. It depends on the phase of the Moon.


Ans: B. We cannot tell with the information given.

Physics & Space Science

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