Signup
Welcome to... Canonfire! World of GreyhawK
Features
Postcards from the Flanaess
Adventures
in Greyhawk
Cities of
Oerth
Deadly
Denizens
Jason Zavoda Presents
The Gord Novels
Greyhawk Wiki
#greytalk
JOIN THE CHAT
ON DISCORD
    Canonfire :: View topic - Greyhawk Calendar Project
    Canonfire Forum Index -> World of Greyhawk Discussion
    Greyhawk Calendar Project
    Author Message
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Mon Mar 12, 2018 7:57 pm  
    Greyhawk Calendar Project

    I have only been playing for about a year, however, it has become obvious that the calendars posted online (and even in the various books) are so full of errors as to be almost worthless.

    I have begun compiling data in the form of medieval style illustrations for each day of the GH calendar, and here's my question ... given a holiday, what is the most important aspect of that holiday?

    An example would be Readying 11, which is called "The Great Moon's Glory", but the descriptions say that is because Luna is full and Celene is new. But that is not correct. Luna is leaving the 3rd Quarter and is nearing New, while Celene is in the 1st Quarter.

    The problem is that people appear to have been treating the Oerth system as if it was Liga-centric, rather than Oerth-centric. Unfortunately, the geometry and math of one system doesn't fit the other.

    So, I'm left with moving holidays around. If I'm going to do that, then I'd like to do it properly.
    Apprentice Greytalker

    Joined: Jan 13, 2016
    Posts: 113
    From: SF, CA

    Send private message
    Mon Mar 12, 2018 9:04 pm  

    Saw your question in #greytalk earlier, glad you got your account here.

    I don't have anything to contribute, other than to say that I'm looking forward to seeing what you come up with.
    Apprentice Greytalker

    Joined: Aug 11, 2001
    Posts: 40
    From: Next to Nowhere NV

    Send private message
    Tue Mar 13, 2018 12:31 pm  

    Also glad to happy to see a new 'face' here...

    Your idea has real merit as years ago someone pointed out the discrepancy between being Liga- and Oerth-centric... cannot wait to see what you come up with.
    Master Greytalker

    Joined: May 12, 2005
    Posts: 876
    From: Woonsocket, RI, USA

    Send private message
    Tue Mar 13, 2018 12:32 pm  

    According to the Glossography, Luna is full and Celene is new on the 11th of Readying. I donít know where you see otherwise.
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Tue Mar 13, 2018 7:30 pm  

    The math doesnít work out. Thatís whatís wrong. After running a simulation of the system, it is clear that the Glossography is incorrect. No one apparently ever checked the math when writing the books.
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Tue Mar 13, 2018 8:00 pm  

    https://www.facebook.com/photo.php?fbid=1923720840972813&set=a.101481479863434.3319.100000047481711&type=3

    I hope this posts correctly. Itís meant to be the sample page for Readying 11, albeit without the text.


    Last edited by Windlass on Tue Mar 13, 2018 8:06 pm; edited 1 time in total
    CF Admin

    Joined: Jun 29, 2001
    Posts: 1425
    From: Wichita, KS, USA

    Send private message
    Tue Mar 13, 2018 8:01 pm  

    Windlass wrote:
    The math doesnít work out. Thatís whatís wrong. After running a simulation of the system, it is clear that the Glossography is incorrect. No one apparently ever checked the math when writing the books.


    IIRC the math changed between the Folio and the 1983 boxed set; we did discuss some aspects of these differences recently but I can't find it at the moment. Some of these may be the one I'm thinking of, but I'm off to bed to crash (still exhausted after GaryCon): https://www.google.com/search?q=moon+luna+celene+site%3Acanonfire.com&ie=utf-8&oe=utf-8&client=firefox-b-1

    Allan.
    _________________
    Allan Grohe (grodog@gmail.com)
    http://www.greyhawkonline.com/grodog/greyhawk.html
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Tue Mar 13, 2018 8:05 pm  

    Lots of discussion of the moons and Liga as gods, but nothing I can see regarding the rotational mathematics of an OERTH centered system.
    Apprentice Greytalker

    Joined: Jul 17, 2017
    Posts: 58
    From: 41į6'53"N, -73į24'21"W

    Send private message
    Sat Mar 17, 2018 11:46 am  

    This reminds me of my (small) attempt at making a Flanaess calendar:

    http://dnd.schadenfreudestudios.com/books/greyhawk/calendar%20%28greyhawk%29.pdf

    Öwhich also reminded me of the discrepancy of Celene's phases due to it appearing full at every holy week, giving it an inconsistent set of weeks between phasesó3/3/3/4.

    Could it be possible that Luna has a somewhat oblong orbit? Circular for ĺ of the time, but shunted further away for the remaining ľ? (Wouldn't be the weirdest celestial phenomena is Greyspace; kind of got the urge to draw a "Spectre-chan.")

    Speaking of such things, if I may askÖ when was the "Day of the Great Signing?" I know it was in Harvester, 584CY, but I don't recall ever hearing what day it was heldóif I had to choose I'd go with Godsday on the 4th of the month, since the waxing of Celene and the waning of Luna makes me think of two opposing forces coming together.
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Sun Mar 18, 2018 12:27 pm  

    I looked at the calendar pages you posted. Having done the math, and plotted out the orbits, the discrepancies come up not because either moon has an oblong orbit, but because Liga moves.

    Think of each moon as racing along a track, and Liga is at the finish line. Liga keeps moving the finish line, slower than either moon is moving, but moving the line nonetheless.

    It takes Luna less time than Celene to catch up to the line, but it still distorts the phases for each moon. So much so that the phases are not regular. By that I mean that a moon is not always full or new (or anything) on a Godsday.

    In fact, on Coldeven 25, Luna is actually in its 1st Quarter, and Celene is in its 3rd Quarter.

    Iím about 91 pages into the illustrations for the book at the moment. Posting pictures to this forum is a bit of a pain, but Iíll be posting pages on Facebook, if anyone is on there. Iím Ricky Maveety. Iíll post CE 25 if you want to see it.
    CF Admin

    Joined: Jun 29, 2001
    Posts: 1425
    From: Wichita, KS, USA

    Send private message
    Mon Mar 19, 2018 7:44 pm  

    Windlass wrote:
    Iím about 91 pages into the illustrations for the book at the moment. Posting pictures to this forum is a bit of a pain, but Iíll be posting pages on Facebook, if anyone is on there. Iím Ricky Maveety. Iíll post CE 25 if you want to see it.


    Shot you a PM on FB :D

    Allan.
    _________________
    Allan Grohe (grodog@gmail.com)
    http://www.greyhawkonline.com/grodog/greyhawk.html
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Mon Mar 19, 2018 9:49 pm  

    Got it!
    Master Greytalker

    Joined: Jan 05, 2002
    Posts: 870
    From: Sky Island, So Cal

    Send private message
    Fri Mar 30, 2018 10:11 am  

    Windlass wrote:
    It takes Luna less time than Celene to catch up to the line, but it still distorts the phases for each moon. So much so that the phases are not regular.


    Nearly two decades ago I worked with Gary Holian to come up with a calendar of eclipses for Oerth (sun and both moons). My memory of it is appropriately weak, but I remember one of my first conclusions being that the phases of the moons could not be caused by light from Liga, so I had to invent a different assumption.

    Your difficulty with the math may be because you are assuming that Liga is causing the phases of the moon the way our sun causes the phases of Earth's moon.
    _________________
    My campaigns are multilayered tapestries upon which I texture themes and subject matter which, quite frankly, would simply be too strong for your hobbyist gamer.  http://www.youtube.com/watch?v=7Mp7Ikko8SI
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Thu Apr 05, 2018 9:48 am  

    Kirt wrote:
    Windlass wrote:
    It takes Luna less time than Celene to catch up to the line, but it still distorts the phases for each moon. So much so that the phases are not regular.


    Nearly two decades ago I worked with Gary Holian to come up with a calendar of eclipses for Oerth (sun and both moons). My memory of it is appropriately weak, but I remember one of my first conclusions being that the phases of the moons could not be caused by light from Liga, so I had to invent a different assumption.

    Your difficulty with the math may be because you are assuming that Liga is causing the phases of the moon the way our sun causes the phases of Earth's moon.


    Interesting. Can you give me a citation as to where the light comes from? If Liga is not causing the phases of the moons, then it can't be causing day or night either, in which case, of what use is it? Not that it has to have a use, but I'm curious.

    And, just so you know, I'm not having any problem at all with the math. It's sort of my thing. The problem I am having is that people haven't applied the math properly to the issue before. They basically took the geometry from the festival days and then tried to shoehorn it into a regular pattern in a non light emitting body centric system.
    Master Greytalker

    Joined: Jan 05, 2002
    Posts: 870
    From: Sky Island, So Cal

    Send private message
    Mon Apr 09, 2018 1:40 pm  

    Windlass wrote:

    Interesting. Can you give me a citation as to where the light comes from? If Liga is not causing the phases of the moons, then it can't be causing day or night either...


    No citation - as I said, the idea that the phases of the moons were not caused by Liga was my invention, not something I read. I'm not sure what I came up with (the original file is on a 3.5" floppy) but I think I might have said the moons are illuminated by proximity to the constellation of Richfest and de-illuminated by proximity to the constellation of Needfest, and that this radiation passes through them rather than being blocked like light would be blocked. Maybe.

    As for your claim that the light that causes day and night on Oerth CAN'T be different from what causes the phases of the moon - why not? If you want to have real world physics controlling moon phases, go ahead - but I don't think there are any canon sources that explicitly say that it is sunlight that causes the phases of the moons - that's your assumption.

    We are agreed that the numbers / dates given for the cycles of the moon do not match their phases as described based on the assumption that it is sunlight that is causing the phases. You are choosing to change the dates based on your assumption that moon phases and daylight have a consistent cause, I chose to (I think) keep the phases as listed and change the assumption about what was causing them. I don't see one approach as being inherently more valid than the other.

    Windlass wrote:

    And, just so you know, I'm not having any problem at all with the math. It's sort of my thing. The problem I am having is that people haven't applied the math properly to the issue before. They basically took the geometry from the festival days and then tried to shoehorn it into a regular pattern in a non light emitting body centric system.


    I didn't mean to imply that you couldn't do the math required. When I said "your difficulty with the math" I simply meant your difficulty in accepting the consequences that follow from the math which you are perfectly capable of doing.
    _________________
    My campaigns are multilayered tapestries upon which I texture themes and subject matter which, quite frankly, would simply be too strong for your hobbyist gamer.  http://www.youtube.com/watch?v=7Mp7Ikko8SI
    Apprentice Greytalker

    Joined: Mar 12, 2018
    Posts: 8


    Send private message
    Wed Apr 11, 2018 4:02 pm  

    Got it. You made something up. I'll stick with what is canon in the books (such as the rotation of Luna, Celene, and Liga), that is the basis for the rest of the stuff. It is easy to calculate the eclipse times, sunset and sunrise, and other celestial events based on that, and since there are known errors in the existing calendars, I feel less awful about correcting them.

    I'm just not one to stick a magical bandaid on something that is a solvable problem. I'm more of a math wonk, and the former seems (to me anyway, as an easy way out).

    So really I'm looking for more information on how the holidays would be set under a system that actually works at more than just the festivals. I'm about half of the way through the book with the artwork and research into eclipses and meanings of holidays.

    Also doing an animation that looks like it will turn out pretty well.

    Thanks for your input.
    Master Greytalker

    Joined: Nov 01, 2007
    Posts: 699
    From: NOW IN Cape May, NJ! Loving the new digs!

    Send private message
    Thu Apr 12, 2018 1:23 am  
    Re: Moon Charts and Calendars

    So, I'm not really sure how you're doing your math, and I don't know what kind of model you're using, but, I think that somehow, your model is coming up with positions or whatever that aren't reflecting what we know is canon.

    The way these things go, for me personally, is that if there's something in the books that I don't understand, it's not going to be that I change the information to suit me, I'm going to change my PoV so that it lines up with the books. Rather than change the dates, I think we ought to try maybe, like, starting with the moons in the phases that they are stated, and tryin gto figure out how we can work a system that would put the moons in the proper phases. Instead of trying to figure out why it's wrong, perhaps we can work toward figuring out how it works so that it's right.

    Here's another moon chart that may help the conversation, since we're having a difficult time envisioning the topic.
    Cick the image to see a larger version. ... or click here.


    _________________
    Owner and Lead Admin: https://greyhawkonline.com
    Editor-in-Chief of the Oerth Journal: https://greyhawkonline.com/oerthjournal
    Visit my professional art gallery: https://wkristophnolen.daportfolio.com
    Paladin

    Joined: Sep 07, 2011
    Posts: 833
    From: Houston Texas

    Send private message
    Wed Jul 25, 2018 5:03 pm  

    This version of an explanation might prove helpful... I was questing for something else and came across this .. haven't done a hard math check, but premise looks sound... for those that "like that level of crunchy"

    DLG

    https://www.nirgal.com/games/rpg/greyhawk/tides_math
    Display posts from previous:   
       Canonfire Forum Index -> World of Greyhawk Discussion All times are GMT - 8 Hours
    Page 1 of 1

    Jump to:  

    You cannot post new topics in this forum
    You cannot reply to topics in this forum
    You cannot edit your posts in this forum
    You cannot delete your posts in this forum
    You cannot vote in polls in this forum




    Canonfire! is a production of the Thursday Group in assocation with GREYtalk and Canonfire! Enterprises

    Contact the Webmaster.  Long Live Spidasa!


    Greyhawk Gothic Font by Darlene Pekul is used under the Creative Commons License.

    PHP-Nuke Copyright © 2005 by Francisco Burzi. This is free software, and you may redistribute it under the GPL. PHP-Nuke comes with absolutely no warranty, for details, see the license.
    Page Generation: 0.21 Seconds