Word Love Thread: Weather and Astronomical Phenomena

With a massive hurricane bearing down on the southeastern US coast, maybe this thread is in bad taste. Forgive me if it is.

But I've meant to do this for a while.

I mentioned this one in the Topography thread -- "rain shadow."

My favorite weather-related term right now is blue norther, also called I think "Texas norther:"

A Blue Norther is a fast-moving cold front that causes temperatures to drop dramatically and quickly. Common characteristics are a dark blue-black sky, strong winds, and temperatures than can drop 20-30 degrees Fahrenheit in a few minutes.

Speaking of things which are said to be blue, the conventional claim about what a "blue moon" is, or was, is wrong.

Usually a season has three full moons in it, but sometimes it has four. Particularly around Easter-- as the most important religious holiday in Christendom is determined according to the moons -- it's important to keep track of the moons.

The almanac also follows certain rules laid down as part of the Gregorian calendar reform in 1582. The ecclesiastical vernal (spring) equinox always falls on March 21st, regardless of the position of the Sun. Lent begins on Ash Wednesday, 46 days before Easter, and must contain the Lenten Moon, considered to be the last full Moon of winter. The first full Moon of spring is called the Egg Moon (or Easter Moon, or Paschal Moon) and must fall within the week before Easter.

When is the Moon 'blue,' in a calendrical sense? According to the Maine almanac, a Blue Moon occurs when a season has four full Moons, rather than the usual three. This type of Blue Moon is found only in February, May, August, and November, one month before the next equinox or solstice. According to modern folklore, a Blue Moon is the second full Moon in a calendar month. This type of Blue Moon can occur in any month but February, which is always shorter than the time between successive full Moons.

At last we have the "Maine rule" for Blue Moons: Seasonal Moon names are assigned near the spring equinox in accordance with the ecclesiastical rules for determining the dates of Easter and Lent. The beginnings of summer, fall, and winter are determined by the dynamical mean Sun. When a season contains four full Moons, the third is called a Blue Moon.

Why is the third full Moon identified as the extra one in a season with four? Because only then will the names of the other full Moons, such as the Moon Before Yule and the Moon After Yule, fall at the proper times relative to the solstices and equinox.

See this Wikipedia entry for more.

Now, if there's a fourth moon in the spring season, it screws with the dating, and so they name the intruder moon a "blue moon" to keep the other moons with their proper ecclesiastical names.

Apparently in the mid-seventies a magazine tried to figure out why almanacs called some blue moons "blue" but they got it completely wrong. It was not, in fact, the second full moon in a calendar month. It was one of four full moons in a season which usually has three.

But over time, this mistaken etymology -- "the second full moon in a calendar month" -- has been accepted as the "modern" definition, because it's easy to explain and people like easy explanations. Even when they're not only wrong, but known to be wrong. Provably wrong.*

And on that general point, I like this list of the names of the full moons, largely taken from Indian names for the moons.

This Space.com article offers some other variations (different tribes had different names for the moons), and notes the moons specifically for 2016.

By the way: November 14, 2016 should be a special holiday for Morons.

It's the Full Beaver Moon.

It really should be a thing. Valentine's Day for men.

* To be honest, I still dispute that "blue moon" originally had this meaning. I prefer to think it meant -- simply, tangibly, poetically -- a moon which appeared more blue than other moons.

As it was rare, "once in a blue moon" became a saying.

Then, later, needing a name for these occasional intruder moons in a season, some wise guy got the idea to just call the spare moon a "blue moon."

I'm very wary of folk etymologies and this whole Blue Moon thing sounds like one to me.

And I just can't get past the idea of a genuine blue moon being an electrifying and resonant image -- and I recoil from the idea that it's just some bullshit word a Lunar Accountant made up to keep his Moon Books straight.

I've seen gigantically luminous yellow moons and of course huge orange moons (usually in fall, the Hunter's moon).

I just can't get past the idea that when people used to speak of a blue moon, they meant, simply, "a moon which is blue."

posted by Ace at 07:32 PM

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