if it follows a 24 hour rotation like earth it would in a 24 hour period cross over the others, they all move together i assume in a way that would allow this moon to have phases so like the moon which would cross over the planets would too only they are much /much/ larger than a moon so they would be visible each time they crossed

https://www.youtube.com/watch?v=L8wgJK9S45I start at 45 seconds and assume the small sun is the moon surounding the three planets, now bretend the small sun is the three planets orbiting the sun, if they all rotate then they should have periods where they have lunar phases, because of the nature of gravity the moon, even if magically powered, should move in the same general way as the other planets. this means the moon would have to go closer and farther to the sun giving it phases, the planets following the same general angle would also move around meaning that they would have to each wax and wane in their daily orbit


short of it the planets would have to circle each other while circling the sun for a moon to be able to orbit all three of them, physics demands it. giving them roughly equal parts of the moon of course means they must be fairly level with each other which would mean they'd have to cross each other to rotate

If their orbits are at a very slight angle -- all it takes is to deviate from flat by one planetary diameter -- then eclipses will only happen when the planets are both coplanar and at the same point in their orbits.

but then that messes up the orbit of the moon in relation to the planets

do the planets not have phases to the moon or have only partial visibility?

No it doesn't, not any more than our own moon's orbit is messed up -- our moon is 5 degrees off the ecliptic plane but that doesn't cause any problems.

I can't see any reason not to have phases, and I figure that Toamna might not be visible in the sky during the part of the lunar month where it's on the other side of the sun from the observer.

but it would have to move around all the planets, if it takes 14 days to go around one then it mean copious amounts of time with no moon at all

Probably so. It stands to reason, really, that a moon that's only visible in the sky half the time, with a lunar month that's probably a large fraction of the solar year, that Toamna would be a mystical presence, and festivals would be scheduled around such events as its perigee or its first appearance of the season.

In fact, I would assume Nox Nocturnalis occurs on the perigee, since that's when Toamna would be closest.

as bullshitty as that is it would make sense though it still leaves a lot of questions unanswered and makes me worry about the aquatic life

Well, Deivai is home to the biggest variety of aquatic life, and it IS the planet with its own moon, so it sort of makes sense there too.

makes me wonder if the other two planets were uninhabited and if they used to be natural or is they were made by the peoples of the first

Well, remember that Trisphee's solar system used to be very different in the past until things got out of hand; Toamna's magically-enforced behavior is there to preserve the worlds, so there could easily be things there now that might not have evolved on their own where the planets are now.

is the sun dying?

I wonder why you ask that question Choco? *curious* Well after reading all this I think it would be difficult to do a divination system without having actual details of eclipses and the effect of the roving moon and so forth. Very complex system. The only stumbling block is there is no real schematic of the orbits and relative distances and of the eccentric moon movement.

choco is one of those people who, if he has asked a question that leads to another, will keep asking until whomever he is asking says to go away X'D i know a little tiny bit about planets and physics and stuff so this is something i can know enough about to have a need to ask questions

exactly as nexy has said, everything speculated in this thread is answerable with magic >.>