Re: Calendars . . . and the planet moons

James Landau wrote: (re the Kash/Cindu calendar)

 > That's neat! I've seen a site that keeps track of exactly what the date is
on the Mayan calendar; maybe someone could create a site that would run a clock
to give you the time and date for their own concalendar.
 That would be neat, but certainly beyond my capabilities. Could probably do it
by hand, though I suspect it would be another case of getting different answers
every time........
    
    
 >As for the planet site: I've discovered it only allows you to deal with one
moon. Will that ruin the accuracy of calculating the length of a day for a
two-mooned planet? If so, can I just add together the masses of the two moons
to give an accurate representation?
 Do you mean the Cal.State site I sent? Yes, it's true, only one moon allowed.
I think she mentions that two or more moons are very difficult to calculate.
(Though I'm told there are formulae.) One of the books recommended there,
Gillett's World Building IIRC, glosses over the topic for the same reason.
Likewise multiple suns. (Cindu, unfortunately, has two moons, but since
planetary physics is not my forte, I don't really know how they work.)
 Seems to me that length of day pretty much has to be assumed/given, as an
average, and so must have the moon's (or plural) effect already factored in.
Perhaps a quite large moon with a quite eccentric orbit, might have a braking
effect when it is close to the planet, but I'm guessing here.
 Nik Taylor's world, IIRC, has a double sun, and, judging by past msgs., he
seems quite knowledgeable about such things. Perhaps he could weigh in on this
question......??