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From: Frank Reed
Date: 2024 Jul 20, 15:39 -0700
Bill Ritchie, you wrote:
"I calculate the Moon's most Southerly Declination this cycle was S28° 25.01'. It occured today (July 19th) at 11.00 UT. There's no point in being more precise because she was "at a standstill". Her most Northerly Declination will be slightly greater, at N28° 28.15', on August 1st at 05.42 UT."
That looks good. And what do you find for the actual extreme southern Dec for the entire 18-year period? It's still a few months away, right?
For my money, the most interesting scenario here was last month: Full Moon occurred very close to the day of the solstice, which meant that the most southerly declination occurred on the day of the Full Moon. That's the most extreme case, and, I would think, most interesting from a "general observation" and "public interest" point of view. The Full Moon is directly opposite the Sun, so on that day the Moon should have been rising just as the Sun was setting. But it was much delayed because of its very low declination. And at the other end of the Moon's passage, it set well before sunrise. Excluding the days right around New Moon, it doesn't seem that there would be very many days when the Moon and Sun are not visible in the sky at the same time at least for some portion of the day. That was one! And it was because the Sun was so far south of the ecliptic right at the time of the Full Moon on the solstice. :) How rare is that, in fact? Specifically, excluding three days right around New Moon, how many days are there in an average year when the Moon is never visible while the Sun is in the sky, even for a few minutes, for a mid-latitude observer? Is it rare (I haven't thought this through, so maybe it isn't at all...)?
Frank Reed