I calculated Skyrim's Lunar Calendar

[LeftoverPat]

I wanted to share a project I've been working on. Enjoy the lore sprinkled in.

I made a lunar calendar of Masser & Secunda, and discovered some cool mechanics and patterns along the way. If you're interested in a visual explanation, here is a youtube video I made to accompany this post.
https://youtu.be/mEZDke4-sgk

Here is the calendar link. I'm honestly terrible at Sheets so... amazed I was able to do this much! But if anyone wants to use/improve/copy for your own use, you are welcome to.
https://docs.google.com/spreadsheets/d/1nO-DTy1innXqqstmiWx11ZFfGCqO4B980Y85_UHSkoo/edit?usp=sharing

Some Observations

• Masser changes its phase every 3 nights. Secunda loosely follows this, but I'll explain this in a bit.
  
• Masser's lunar zenith happens every 24h at midnight. Always. (AKA highest point in the sky).
  
• Secunda's lunar zenith happens every 20h. This means you'll see it peak at 12am one night, followed by 8pm the next, 4pm, 12pm, 8am, 4am, etc respectively. This is slightly common knowledge after a google search, but here's where it gets interesting.
  
• Despite this, Secunda will have 5 possible positions relative to Masser. For example, the position where Masser & Secunda align happens every 5 nights.
  
• Masser's phase changes when it's below the horizon.
  
• Secunda's phase should theoretically change with Masser, but in both Oblivion & Skyrim, Secunda can sometimes be above the horizon while Masser is below, so it can't just change before our eyes. This partially explains why Masser & Secunda can appear to have different phases on some nights - Secunda can "skip ahead" a phase on Masser's third night if it is in the final 2/5 clockwise positions. I've dubbed this the third night paradox.
  
• Secunda does have a phase shift pattern, though. It changes phase every 4 nights, then 2 nights, then 4, then 3, then 2, before repeating this pattern. 4-2-4-3-2. Over 15 nights, Masser: 3-3-3-3-3; Secunda: 4-2-4-3-2.
  
• This entire jumble of phase combinations makes for seemingly unpredictable line-ups. But the "big pattern" does repeat - every 120 days, to be exact. So on 15 Evening Star 4E201, the Full Moon patterns will be the same as they were on game start 17 Last Seed 4E201. This repeat is marked in bright red on the calendar linked above.
  
• Now you might ask: What Khajiit furstock phases exist in game? Suffice it to say, out of the 16 forms in Three Booksellers (not counting Mane), only 8 of these phases exist ingame. These would only produce: Suthay, Suthay-raht, Cathay, Cathay-raht, Senche, Senche-raht, Dagi, Dagi-raht.

Fun Trivia/History

• Both Oblivion/Skyrim share the same moon mechanics.
  
• Morrowind's "weird" mechanic where Secunda seems to slow down & catch up to Masser due to a different angle appears to be the most similar sky to Oblivion's Orrery.
  
• Daggerfall had no visible overworld moons. But had 2 full moons happen close to each other in the background, for Lycanthropes.
  
• Arena, despite this popular image, has one, large, white moon that both travels across the sky and changes phases AND changes moonrise positions depending on the day (works similar to Skyrim's ingame constellations).
  
• ESO is my fav b/c it uses irl hours. With some help from Dave @ UESP, I learned that every ingame ESO day lasted exactly 20955 seconds, and a complete moon cycle lasts 30 days. Divide by 8 (per phase), and we see each phase lasts ~3.75 ingame days. Or 21.825 irl hours.

This project was hugely inspired by u/kingjoe64 who is a legend in his Elder Scrolls moon research.

Anybody found mechanics like this that go much deeper? Seriously making me look twice at the moons every time I play a TES game.

[Local Cinnamon Roll]

Thank you so much for this! Hopefully I won't randomly turn into a werewolf every time I fast travel to one of the main cities because I can (mostly) tell when the moon phases are and when I turn :)