If the intrinsically brightest stars in Earth's sky have absolute magnitudes of -10, how bright (in terms of total energy output per second) are these stars compared with the Sun, whose absolute magnitude is +4.8? A) about 14.8 times brighter B) about 800,000 times brighter C) about 8000 times brighter D) about 10¹⁵, or 1,000,000,000,000,000, times brighter

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The brightness of a star compared to another can be calculated using the formula for the difference in magnitude, which is $2.512^{(M_1 - M_2)}$, where $M_1$ and $M_2$ are the absolute magnitudes of the two stars. Using -10 for the brightest stars and +4.8 for the Sun, the calculation is $2.512^{(-10 - (+4.8))} = 2.512^{-14.8}$, which is approximately 800,000 times brighter.

If the Intrinsically Brightest Stars in Earth's Sky Have Absolute