12 per diem: All things Lune-y.

O swear not by the moon, th'inconstant moon
That monthly changes in her circled orb,
Lest that thy love prove likewise variable.
—Shakespeare

It's a pretty magical alignment tonight: a blue moon, new year's eve, and an eclipse. I had read a very interesting article (thanks, Jeremy P!) about how we get blue moons and how what we call a blue moon is really not (supposedly), and I can't quite wrap my head around it. Very interesting stuff, and a lot of very intelligent people have worked it all out, so I can afford to be very trusting. And to make it all even more interesting (to me) there is the whole tie-in to the ecclesiastical calendar/church year/etc that I've also been trying (mostly unsuccessfully) to wrap my noggin around.

Here are a few more interesting bits from around the web. Enjoy that most mysterious, mystical, beautiful and lunatic-al little satellite orb of ours tonight.
And Happy New Year!

from boosharticles.com
new years eve lunar eclipse – when and where
A blue moon and a partial lunar eclipse – what more can you ask for on new years eve?
Well, tonight (December 31) both a very rare lunar eclipse and a “blue moon’ will take place.   The lunar eclipse will be visible between 6:52 p.m. to 7:54 p.m GMT, from all parts of earth where the moon will be above the horizon when the eclipse occurs: Asia, Africa, Europe, Greenland and most of Australia and Alaska. North and South Americans will have to wait for the next eclipse. Scientists say that this is the first time in 353 years that a lunar eclipse occurs on new years eve.   A lunar eclipse is an eclipse which occurs when the earth is between the moon and the sun, thus blocking the sun ray’s from reaching the moon. A lunar eclipse can only occur when the moon, the sun and the earth are almost exactly aligned. with the earth in between. This also means that a lunar eclipse can only occur when there is a full moon.   The Blue moon is a bit less exiting, because it is both not visible and not as rare. This phenomenon occurs very 2.7 years. The last time there was a blue moon on new years eve was in 1990. The next time will be in 2028.   So what is a blue moon? In simple terms, a blue moon is an extra full moon. While most years have 12 full moons (one every month), some years have 13 full moons, because the lunar calendar and the solar calendar don’t match. The lunar cycle is 29.5 days, but the solar cycle is a bit longer, and contains roughly eleven days more. When these accumulate to a month, there is an extra full moon – the blue moon.

from skyandtelescope.com (and another one here)
What's a Blue Moon? The trendy definition of "blue Moon" as the second full Moon in a month is a mistake.

by Roger W. Sinnott, Donald W. Olson, and Richard Tresch Fienberg

Recent decades have seen widespread popular embrace of the idea that when a calendar month contains two full Moons, the second one is called a "Blue Moon." The unusual pattern of lunar phases in early 1999 — two full Moons each in January and March, and none at all in February — triggered a groundswell of public interest. Countless newspapers and radio and TV stations ran stories about Blue Moons.
In an article "Once in a Blue Moon", folklorist Philip Hiscock traced the calendrical meaning of the term "Blue Moon" to the Maine Farmers' Almanac for 1937. But a page from that almanac belies the second-full-Moon-in-a-month interpretation.
With help from Margaret Vaverek (Southwest Texas State University) and several other librarians, we have now obtained more than 40 editions of the Maine Farmers' Almanac from the period 1819 to 1962. These refer to more than a dozen Blue Moons, and not one of them is the second full Moon in a month. What's going on here?

from Sierra Trading Post:
Rare New Year’s Eve Blue Moon Tonight!
by Allie Comeau on December 31, 2009
Okay, so it’s not an actual blue moon (the moon tonight will still be white) – but it IS a numerological blue moon.

The full moon tonight is the second full moon of the month – a rare astrological occurrence that only happens, well, once in a blue moon.
The fact that it’s happening on New Year’s Eve this year is even rarer – the last blue New Year’s Eve moon was in 1990. So if you’re out on the town for New Year’s Eve this year, be sure to look toward the sky and take a minute to bask in the light of the blue moon. You might not see another one for quite some time.
And in case you’re wondering, actual blue moons do occur (but those are even more rare). The moon will take on a bluish tint if there are particles in the air big enough to scatter red light. The last time the moon turned blue was in 1886 after the eruption of Krakatoa in Indonesia, which according to Wikipedia, was one of the most violent volcanic events in recorded history. The explosion ejected 21 cubic kilometers of ash – and effectively turned the full moon blue.

and my favorite part of the article from PanicBlog:

Blue Moons
The article that told me I was wrong about what “blue moon” means (and hilariously refers to that definition as “trendy”) explains that the “two full moons in a month” definition is due to a misreading of the Maine Farmers’ Almanac: the real Blue Moon is the third full moon in a season that has four full moons. Why the third? The first full moon of the season is particularly significant; e.g., the Easter moon. The moons before and after have names as well–the Lent Moon precedes the Easter Moon, whether it’s the third or fourth moon of the winter–so the third moon of four is the extra one. By this definition, 2009 does not have a blue moon, since the full moon on December 31st is after the solstice and belongs to next year’s winter.

For an example of the importance of the sequence of the moons to daily life, consider Charlemagne’s naming of the months of the year (a solar year, but even so), used for over 700 years after his death:

Wintarmanoth, winter month
Hornung, the month when the male red deer sheds its antlers
Lentzinmanoth, Lent month
Ostarmanoth, Easter month
Wonnemanoth, love-making month
Brachmanoth, plowing month
Heuvimanoth, hay month
Aranmanoth, harvest month
Witumanoth, wood month
Windumemanoth, wine month
Herbistmanoth, autumn harvest month
Heilagmanoth, holy month