Blue Moon?

Modern folklore has it that full moons make for better parties and higher booking rates at mental hospitals, but the studies I've heard about seem to deny the relationship.

At least once this week you have probably heard through the media that the old year (for purists, the decade of the eighties) is going out on a blue moon. People have been saying that "according to folklore" a second moon in a calendar month is a "blue moon." So, they say, this is the origin of the phrase "once in a blue moon." Don't believe them! "Once in a blue moon" is old, about 150 years old, but the age of the two-full-moons-in-a-month meaning of "blue moon" is less than ten years. The older meaning may be wishy-washy and the newer one solid and technical, but don't let anyone tell you they have replaced one with the other.

It's not rare to see two full moons in a month. Because the moon and our calendar are not in sync and all the months but February are longer than the moon's synodical cycle, it happens about seven times in every nineteen years. That's every thirty-three months on average. Months have different lengths, so the phenomenon moves around a bit. In 1999 there will even be two "blue" moons. If you think about it, it's a little like getting paid every second Friday and finding some months you get paid three times instead of twice.

Meaning is a slippery substance. The phrase "blue moon" has been around a long time, well over 400 years, but during that time its meaning has shifted around a lot. I have counted six different meanings which have been carried by the term, and at least four of them are still current today. So that makes discussion of the term a little complicated.

The earliest references to the term are in a phrase remarkably like early references to "green cheese." Both were used as examples of obvious absurdities about which there could be no argument. Four hundred years ago, if someone said, "He would argue the moon was blue," the average sixteenth century man would take it the way we take, "He'd argue that black is white." This understanding of a blue moon being absurd (the first meaning) led eventually to a second meaning, that of "never." To say that something would happen when the moon turned blue was like saying that it would happen on Tib's Eve (at least before Tib got a day near Christmas assigned to her).

But of course, there are examples of the moon actually turning blue; that's the third meaning — the moon visually appearing blue. When the Indonesian volcano Krakatoa exploded in 1883, its dust turned sunsets green and the moon blue all around the world for the best part of two years. In 1927 a late monsoon in India set up conditions for a blue moon. And the moon here in Newfoundland was turned blue in 1951 when huge forest fires in Alberta threw smoke particles up into the sky. Even by the nineteenth century it was clear that although visually blue moons were rare, they did happen from time to time. So the phrase "once in a blue moon" came about. It meant then exactly what it means today — that an event was fairly infrequent, but not quite regular enough to pinpoint. That's meaning number four, and today it is still the main one.

I know of six songs which use "blue moon" as a symbol of sadness and loneliness. In half of them the poor crooner's moon turns to gold when he gets his love at the end of the song. That's meaning number five: check your old Elvis Presley or Bill Monroe records for more information.

Finally, in the 1980s, comes the most recent meaning of blue moon — the second full moon in a month. I first became aware of the new meaning of the term in late May 1988 when it seemed all the radio stations and newspapers were carrying an item on this interesting bit of "old folklore." At the MUN Folklore & Language Archive we get calls from all over, from people wondering about bits of folklore, and in that month I got calls about blue moons. You see there were two full moons that month. There hasn't been such a month since then, until this month. December 1990 has full moons on the 2nd and the 31st.

In 1988 I searched high and low for a reference to the term having this meaning, or for any other term used to describe two moons in a single calendar month. But it was all in vain. There just seemed to be no history to this term. Through that research I uncovered the information on other meanings of "blue moon." But not this blue moon, meaning number six.

This month, with the new "blue moon" coming on, I started getting calls again and I searched harder this time. I had already exhausted all the usual sources of historical and astronomical dictionaries, indexes of proverbial sayings and the like. A brand new edition of the huge Oxford English Dictionary had come out in the meantime, but even that seemed to have nothing on this new usage. A new tack was called for. Almost every day I use computer networks to contact other folklorists around the world (in fact I send this column all around the world each week on one of the networks), so I started with them. But no one could give me an earlier use of the term than the 1988 wire stories. I then turned to other computer networks, for scientists and especially astronomers. Still no luck. "Blue moon" seemed to be a truly modern piece of folklore, masquerading as something old.

Then I remembered that the term was a question in one of the Trivial Pursuit boxes, the "Genus II edition," which was published in 1986. Trivial Pursuit is a fine company for scholars — they keep all their files and they can tell you the source of any bit of information in their games. Yes, they told me, that question came from a certain children's "Facts and Records" book, published in 1985. Where the authors of that book got it, no one seems to know.

The term, used this way, must have been very, very local before the publication of the children's book, so local that it was never written down by amateur or professional astronomers, or by the newspapers which might have been searched by dictionary makers. It certainly was very rare. Perhaps it was even made up by the authors of the children's book as a safeguard against plagiarism. This is sometimes done in order to be able to prove in a law court that a later work has stolen from your own — how else would they have gotten something which you invented? Well, if this is what the authors did, they have lost out because the term immediately entered the folklore of the modern world and it has become as living a meaning of the term "blue moon" as any of the earlier ones. Since it has a kind of technical meaning which most of the earlier meanings lacked, it will probably last a whole lot longer, too. "Old folklore" it is not, but real folklore it is.

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