December 28, 2009

Blue Moon

A lunar month takes 29.53 days. This is the amount of time it takes for the Moon to complete a cycle through all the phases, from new moon to full moon and then back to new moon again. This is very close to the length of a month in the Western calendar, which usually have 30 or 31 days. Every month usually has one of each of the phases. So a typical month will have a new moon, first quarter, full moon and last quarter moon. But every now and then, a month will have two of the same phases. When a month has two full moons, the second one is called a "blue moon".

Blue moons are rare, and that's where the phrase comes from, "once in a blue moon". How rare? They always happen once every 2-3 years (2.72 years, to be exact).

So when is the next Blue Moon? December 31, 2009!

The name of the first Full Moon after Yule is sometimes known as the "Wolf Moon" or "Old Moon."

This should make this night very special, not only a full moon on New Year's Eve but the Eve of a new decade!

What would you do that is "once in a blue moon"?

5 comments:

A Lewis said...

How cool is that...on the very last day of the year! It's been clear and cold here all week.....so I'll keep my fingers crossed that I can see it on the 31st. Hugs.

Kelly said...

I noticed it was going to be a full moon on Amature Night... so we have decided to stay in and play it safe, cuz who knows what in the hell is gonna happen that night....Happy New Year!

Dyl said...

You have so photoshopped that picture! :-)

Archerr said...

I didn't realize it was going to be a full moon either. I'll have to watch for it and hope for clear weather. However, it's supposed to be a wintery mix on Thursday night here in DC.

Ur-spo said...

i forgot this is a blue moon month - thank you for remembering it.
I will think of you when I see it.
and wish you well for 2010.