Blue moon
A friend of mine pointed out on August 31 that it was a blue moon. My initial reaction was "Big deal, it's just a sort of aliasing". But later I looked it up in Wikipedia and learned something I found sort of intriguing: The definition of blue moon most of us learned only dates back 66 years, to a misinterpretation in Sky and Telescope (reportedly later reinforced by a radio program named after a Star Trek phrase, StarDate).
The original termology was that each of a season's three full moons had a name. For example, the last one in summer was called the Harvest moon, and the one following it in early autumn the Hunter's moon. But because of aliasing between the lunar and solar cycles, a season sometimes squeezes four full moons in. When that happened, the first, second, and last got their usual names, and the third, the extra one in the middle, was called a Blue moon.
Harvest moon and Hunter's moon sound vaguely familiar to me, and I immediately recognized two of the others from lines of songs:
The original termology was that each of a season's three full moons had a name. For example, the last one in summer was called the Harvest moon, and the one following it in early autumn the Hunter's moon. But because of aliasing between the lunar and solar cycles, a season sometimes squeezes four full moons in. When that happened, the first, second, and last got their usual names, and the third, the extra one in the middle, was called a Blue moon.
Harvest moon and Hunter's moon sound vaguely familiar to me, and I immediately recognized two of the others from lines of songs:
- "Honey moon, keep on shining in June."
- "Have you ever heard the wolf cry to the blue corn moon?" (Found some notes from the lyricist here.) I gather from Wikipedia that Pocahontas would actually have called it Moon When Corn Is Edible (third moon after Moon When Women Weed Corn).