Moon cycles?

[Merkuri]

Is there a schedule of the cycles of Eberron's twelve moons anywhere? I haven't been able to find one. I remember in the ECS that they mentioned that the 12 months are named after the moon that's full during that month, which suggests that the moons all go through a full phase once a year (full to full) and only one moon is full during a given month. But there's a sidebar in Xen'drik about lycanthropes that mentions more than one moon can be full during a given month. In fact, about 19 days out of the month an afflicted lycanthrope can expect to change. So which is it? How fast do the moons go through their phases? Does anyone know, or should I just make something up?

 

[Stone Dog]

Here is the calendar utility for the months and moons and planes. As with everything, adjust to taste, but it is a pretty handy tool. You can even click on a bit that gives you the entire lunar pattern for a whole month. That will give you plenty of moon cycle information.
http://www.wizards.com/default.asp?x=dnd/ebwe/20041129a

And here is the official web article describing each of the moons with positions, sizes, distances and astrological influences.
http://www.wizards.com/default.asp?x=dnd/ebds/20050307a

Specifically I think this bit addresses your question rather directly.

Lycanthropes and the Moons of Eberron

The full moon has a powerful effect on lycanthropes -- and on Eberron, a shapeshifter may have to contend with the influence of multiple moons on a single night. A creature afflicted with lycanthropy changes involuntarily into animal form whenever one of the twelve moons is full. An afflicted creature can resist the involuntary transformation with a successful Control Shape check (see Monster Manual, page 303); however, for each additional full moon after the first, apply a -2 penalty to the check.

This means that an afflicted lycanthrope has to contend with the effects of the curse an average of nineteen nights of the month. Thus, rarely does an afflicted lycanthrope last a week before the curse takes hold and permanently alters her alignment.

That should take care of you for a while.

 

[Glyfair]

The general philosophy is "use what fits the story." However, there is an Eberron World and Planar Calendar Utility on the Wizards site that has a cycle for the moons (and planes) you can use. If you search the forums, I believe the developer mentioned how to tweak it for your own cycles.

 

[Merkuri]

Oh, that's just what I was looking for! Thanks!

 

[Spatula]

One thing I noticed while playing around with this is that Mabar is off-kilter. It's supposed to become coterminous around the winter solstice but instead is doing so closer to the spring equinox in the webtool.

If you download it for your own use, you can fix this by opening up the index.htm file in a text editor and replacing any instance of "422" with "513".

 

[Arlough]

Tidbits:
Last time all the moons were full simultaneously was the first of Zarantyr, -2202.

The next time all 12 moons will be full simultaneously will be on Lharvion 1st, 5305 YK.

The total synchronization cycle is every 7507.5 years.

The cycles (full to full) are as follows:
Zarantyr = 11 weeks
Olarune = 8 weeks
Therendor = 6 weeks
Eyre = 9 weeks
Dravago = 13 weeks
Nymm = 4 weeks
Lharvion = 14 weeks
Barrakas = 15 weeks
Rhann = 7 weeks
Sypheros = 5 weeks
Aryth = 12 weeks
Vult = 10 weeks

That's all for now. Goodnight.

 

[Trolls]

Is there a schedule of the cycles of Eberron's twelve moons anywhere? I haven't been able to find one. I remember in the ECS that they mentioned that the 12 months are named after the moon that's full during that month, which suggests that the moons all go through a full phase once a year (full to full) and only one moon is full during a given month. But there's a sidebar in Xen'drik about lycanthropes that mentions more than one moon can be full during a given month. In fact, about 19 days out of the month an afflicted lycanthrope can expect to change. So which is it? How fast do the moons go through their phases? Does anyone know, or should I just make something up?

Just in case you missed it in the link above, this paragraph from the Moons of Eberron dragonshard answers your question somewhat:

Each moon has an "ascendant phase" -- a 28-day period during which it is unusually bright. To date, scholars have found no natural explanation for this phenomenon, and it remains one of the mysteries of the skies. This cycle of radiance is the basis for the lunar calendar, and each month is named for the moon that is in its ascendant phase. Some stargazers claim that the ascendant moon has a profound impact on the skills and spirit of children born beneath it; a child born in the month of Zarantyr will be wild and mercurial, while a child of Therendor will be gentle and kind. Druids and rangers also believe that the ascendant moon can be a source of strength -- that a child of Dravago has a special gift for calming animals when this moon is full in the sky. A Dungeon Master who wants to embrace this idea can provide a character with a single action point on a night when his ascendant moon is full; this can be used only for an action tied to the theme of his moon.

So the months aren't named for when the moon is full, just when its unusually bright.

Generally, though, I wouldn't bother keeping track of moon cycles until it comes up specifically in game, then just pick whatever is most dramatic!

 

[Merkuri]

Wow, holy necromancy! I asked this question five years ago.

 

[Arlough]

Sorry about that. I was searching for some additional data on the moons and came across this post. I didn't even notice the date.

 

[amerigoV]

Heh, must be a full moon....