Quote Originally Posted by Ghostman View Post
Add one more gas giant, at a far away orbit but close enough so that all 8 other planets will be visible from the homeworld. That way there'll be 9 "wandering stars" known to the people (the secondary sun counts as the 9th), which gives them a nice number to feature in astrology.
and I assume that would be our 8th planet.

The second star is so dim that one or two planets would be brighter but only at their brightest. You see, their brightness will fluctuate a lot depending on their position. On the other hand, the second star will have a variation of only 7% luminosity due to the movement of the planet around the main star. This is considering that the second star is still at 75 AU from the main star. 75 AU (or 11 175 billion km) is what I considered a safe distance that allowed both stars to have their own system. Of course the orbit could be elliptical but I assume that if it's the case, 75 AU is the average distance. That would also influence the brightness perceived from the planet... but these are just details

Planets from the second star (if any) would be impossible to spot in the sky with the available technology. But they are free for speculators.