APOD: Halloween and the Ghost Head Nebula (2016 Oct 30)

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neufer
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Re: APOD: Halloween and the Ghost Head Nebula (2016 Oct 30)

Post by neufer » Tue Nov 01, 2016 3:33 am

cleofus wrote:
Regarding Cross-Quarter day, it is true that Halloween has traditionally been a cross-quarter day which it isn't BUT also Groundhog day is called cross-Quarter day but it isn't either. Figure it yourself: Dec 21 - Mar 21 is 10 days in Dec, 31 in January, plus 28 in February and 20 in March for a total of:
10 + 31 + 28 + 20 + 1 = 90 (ignoring the about ½ day on either end, but adding in 1 to account for both 1/2's)

½ of 90 is 45 which occurs on Feb 4th or 5th

= 10 + 31 + 4 (+1) = 45/46
And 90 days is not half of ~183 days either.

The Sun is not (apparently) moving at a constant rate across the heavens so you shouldn't simply chop 90 days in half.
https://en.wikipedia.org/wiki/Samhain wrote:
<<Samhain (pronounced SAH-win or SOW-in) is a Gaelic festival marking the end of the harvest season and the beginning of winter or the "darker half" of the year. Traditionally, it is celebrated from the very beginning of one Celtic day to its end, or in the modern calendar, from sunset on 31 October to sunset on 1 November, this places it about halfway between the autumn equinox and the winter solstice. In the late 19th century, the pseudo-historians Sir John Rhys and Sir James Frazer suggested that it was the "Celtic New Year." Frazer wrote in The Golden Bough: A Study in Magic and Religion that 1 May and 1 November are of little importance to European crop-growers, but of great importance to herdsmen. It is at the beginning of summer that cattle are driven to the upland summer pastures and the beginning of winter that they are led back. Thus, Frazer suggests that halving the year at 1 May and 1 November dates from a time when the Celts were mainly a pastoral people, dependent on their herds. In medieval Ireland the festival marked the end of the season for trade and warfare and was an ideal date for tribal gatherings. These gatherings are a popular setting for early Irish tales.>>
Groucho Marx wrote:
"I could dance with you till the cows come home. Better still, I'll dance with the cows and you come home."
cleofus wrote:
P.S. SOL is NOT the Latin name for the Sun - Solis is.
https://en.wikipedia.org/wiki/Sun wrote:
<<The Latin name for the Sun, Sol, is not common in general English language use; the adjectival form is the related word solar. The term sol is also used by planetary astronomers to refer to the duration of a solar day on another planet, such as Mars. The English weekday name Sunday stems from Old English (Sunnandæg; "Sun's day", from before 700) and is ultimately a result of a Germanic interpretation of Latin dies solis>>
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bystander
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Re: APOD: Halloween and the Ghost Head Nebula (2016 Oct 30)

Post by bystander » Tue Nov 01, 2016 3:49 am

cleofus wrote:Regarding Cross-Quarter day, it is true that Halloween has traditionally been a cross-quarter day which it isn't BUT also Groundhog day is called cross-Quarter day but it isn't either. ...
Samhain (Nov 01) and Imbolc (Feb 02) are cross-quarter days.
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