
What 'Once in a blue moon' literally means - pavel
http://www.thisisbrandx.com/2009/12/once-in-a-blue-moon-this-new-years-eve.html
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mbubb
Pretty cool. Question though - the definition of a blue moon is for there to
be 4 full moons in a season.

(Learned on HN):

<http://news.ycombinator.com/item?id=1008761>

which cites: <http://en.wikipedia.org/wiki/Blue_moon>

If that is the case then this is not a blue moon as the first 3 happened in
the fall and the 4th is after the solstice. Right?

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btilly
If you had read the Wikipedia article for yourself and you'll find multiple
definitions of a blue moon.

To save you the effort, _The Farmer's Almanac_ used the definition you just
cited, but "2 full moons in a month* is the more commonly used definition.

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mbubb
Yeah you are right.

Or simply gone to nasa.gov:

<http://science.nasa.gov/headlines/y2009/29dec_bluemoon.htm>

"The modern definition sprang up in the 1940s. In those days, the Farmer's
Almanac of Maine offered a definition of Blue Moon so convoluted that even
professional astronomers struggled to understand it. It involved factors such
as the ecclesiastical dates of Easter and Lent, and the timing of seasons
according to the dynamical mean sun. Aiming to explain blue moons to the
layman, Sky & Telescope published an article in 1946 entitled "Once in a Blue
Moon." The author James Hugh Pruett cited the 1937 Maine almanac and opined
that the "second [full moon] in a month, so I interpret it, is called Blue
Moon."

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lmkg
This one's pretty cool since it's happening on the last day of the year and
all. Although, by definition, they can only happen in the last few days of the
month, so it's a little less special than I first thought.

I also remember a few years back, there were two blue moons only two months
apart, something that only happens every couple decades. There was a full moon
in early January, a blue moon on Jan 31st, then the tiny month of February
managed to fit in between full moons, so the next full moon happened on March
1st, with a blue moon later that month.

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roundsquare
* hey?), some believe that a full moon -- not to mention a blue one -- can cause strong emotions to flare. Some evidence shows that arrests for petty crime and public drunkenness increase 5% during a full moon*

Anyone know why? Any ideas on the causal effect? Pure chance?

