5 thoughts on “Chinese New Year: Watch the Skies!”
Calendrical trivia I need to get off my chest:
In Western terms, the Chinese New Year begins on the day of the first new moon (geocentric conjunction) after the first day the Sun enters Aquarius (ecliptic longitude ≥ 300°). The common statement that it's "the second new moon after the solstice" is a general rule but not 100% true. For example, last year it was the third new moon, as the second was on the same day as the sun entering the necessary solar term.
February 8 is also reckoned as a new moon in the Gregorian Calendar, using an arithmetic algorithm that nobody gives a damn about beyond figuring out the date of Easter. But the interesting thing here is that, because of the extra day added after February 23 (long story), this ends up being a "lunation" of 31 days. That this (extra day added to a 30-day lunation) is allowed to happen is part of the compromises made in usability and backwards compatibility with the older Julian Calendar. This doesn't happen often, but how often this happens in the complete 5.7 million year cycle(!) of the Gregorian Calendar is left as an exercise for the reader.
The Muslims are generally the only ones really big on empiricism, but since there's only supposed to be two possibilities for the length of a month, if the new moon can't be seen at the end of Day 29 for whatever reason it's assumed to be at the end of Day 30. Or you do what the Saudis do and send someone up in an airplane to fly above the clouds.
I've seen at least one (serious) author discuss a "lunar date line" where different parts of the Islamic world have different dates depending on what day a particular new moon would or could be visible.
Otherwise, Jews, Christians and the Chinese all just rely on the math: arithmetic for the first two, and whatever the latest astronomical algorithms are for the Chinese.
Calendrical trivia I need to get off my chest:
In Western terms, the Chinese New Year begins on the day of the first new moon (geocentric conjunction) after the first day the Sun enters Aquarius (ecliptic longitude ≥ 300°). The common statement that it's "the second new moon after the solstice" is a general rule but not 100% true. For example, last year it was the third new moon, as the second was on the same day as the sun entering the necessary solar term.
February 8 is also reckoned as a new moon in the Gregorian Calendar, using an arithmetic algorithm that nobody gives a damn about beyond figuring out the date of Easter. But the interesting thing here is that, because of the extra day added after February 23 (long story), this ends up being a "lunation" of 31 days. That this (extra day added to a 30-day lunation) is allowed to happen is part of the compromises made in usability and backwards compatibility with the older Julian Calendar. This doesn't happen often, but how often this happens in the complete 5.7 million year cycle(!) of the Gregorian Calendar is left as an exercise for the reader.
Yes we calendar!
What happens if it's cloudy? Does the New Year wait until it clears up, and what happens to the rest of the calendar then?
This is so complicated.
The Muslims are generally the only ones really big on empiricism, but since there's only supposed to be two possibilities for the length of a month, if the new moon can't be seen at the end of Day 29 for whatever reason it's assumed to be at the end of Day 30. Or you do what the Saudis do and send someone up in an airplane to fly above the clouds.
I've seen at least one (serious) author discuss a "lunar date line" where different parts of the Islamic world have different dates depending on what day a particular new moon would or could be visible.
Otherwise, Jews, Christians and the Chinese all just rely on the math: arithmetic for the first two, and whatever the latest astronomical algorithms are for the Chinese.
The taxes over 532 indiction cycles would be murder.