Those factors definitely affect my measurements, but they can be
acconted for and/or rolled into the uncertainty estimate. The
star also doesn't have a constant brightness but I can still talk
about the average brightness or the brightness at a particular
time. All of these things must be considered but in the end they
affect the truth value of the measurement, not whether there is
a true (objectively real) brightness.
Jason
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Dept. of Physics and Astronomy University of Calgary
jmcvean@acs.ucalgary.ca http://www.ucalgary.ca/~jmcvean
"And it would have worked if it weren't for those meddling kids."
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