In article .com,
"sed" writes:
Does anyone know how to calculate a total brightness of a binary system
if brightness of each individual start and their radial separation is
known?

What's wrong with just adding up the brightnesses of the components?
And why would radial separation matter? Are you asking how to
convert magnitudes to linear units?

If you are asking how to calculate light curves of eclipsing or other
close binaries, which effects to you want to take into account? A
first approximation is as simple as geometry, but doing a good job
for real systems is complex.

--
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
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