Calculating absolute magnitude

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To calculate Sirius A's absolute magnitude, the formula m - M = 5 log(d) - 5 is appropriate, where m is the apparent magnitude and d is the distance in parsecs. Sirius A has an apparent magnitude of -1.5 and is located 2.6 parsecs away, allowing for the calculation of its absolute magnitude. The discussion also seeks to determine how many times brighter Sirius A is compared to the Sun, which has an apparent magnitude of -26.8 and a distance of 1 AU. The equation m1 - m2 = -2.5 log(f1/f2) is mentioned for comparing brightness, with flux needing clarification. Understanding the units for distance and the concept of flux is essential for accurate calculations.
edoarad
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Sirius A has an apperant magnitude of -1.5, and his distance from us is 2.6 pc. the sun has an apperent magnitude of -26.8 and a distance of 1 AU.
what is Sirius's absolute magnitude?
how meny times is Sirius brighter then the sun?



m1-m2=-2.5lg(f1/f2)
this is the equation I'm supposed to use, its the one they gave me.
i think it is much more oppropriate to use:
m-M=5lg(d)-5
and then just dividing to find how much brighter he is.

so, what unit does the distance "d" needs to be in? and how do i calculate the answers with the first equation?
and what is flux? i couldn't get a clear explanation anywhere.
 
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