On 12/19/2010 04:44 PM, Mauro Lacy wrote: > On 12/19/2010 01:28 PM, Mauro Lacy wrote: >> Here's an open version of the same database: >> http://www.hermit.org/Eclipse/when_search.shtml >> I've downloaded the raw file, and after searching for total lunar >> eclipses from Dec 19 to Dec 23, post Oct 15 1582(before that, Julian >> dates are used), I've found the following "solstice eclipse" candidates: >> >> 1638|12|21|01:59|L|T|N-|119||-0.139|2.632|1.605|12960|5760||| >> 1703|12|23|06:30|L|T|S-|120||0.025|2.891|1.763|14160|6360||| >> 1768|12|23|15:07|L|T|S-|121||0.060|2.770|1.757|12840|6000||| >> 1945|12|19|02:20|L|T||124||-0.284|2.355|1.348|12360|4800||| >> 1964|12|19|02:37|L|T||134||0.380|2.171|1.180|11760|3600||| >> 2010|12|21|08:17|L|T||125||0.321|2.306|1.261|12600|4440||| > Wolfram Alpha gives solstice dates for each year easily. According to > wolframalpha, the (northern hemisphere) winter solstice for the year > 1703 occurred Saturday, December 23, 7:04 am LMT. > http://www.wolframalpha.com/input/?i=1703+northern+hemisphere+winter+solstice+date > > LMT stands for Local Mean Time(an old form of timezone, it seems), > because wolfram alpha likes to give local times, based on the location > of the questioner. Searching on how to convert from LMT to GMT(UT), for > western latitudes you have to add the local latitude in degrees divided > by 15 degrees. So, 7:04 am LMT in my latitude is around 11:04 am GMT. > > The last time an eclipse coincided with a (northern hemisphere winter) > solstice, then, was December 23, 1703. Not that this is important, of > course, but is in the name of precision, and of course, of being picky.
In the name of precision (and of being picky) that is wrong. I misread the date of the solstice, which is December 22, not 23. This is off then by around 20 hours. So, neither of those dates coincide with a solstice inside the 24 hours range, and the closer one is December 21, 1638. > According to the same, the winter solstice date for 1638 was 12:20 pm > LMT, Tuesday, December 21. That date is around 16 pm GMT for my > latitude, so the lunar eclipse of that day is out of the 24 hours rule > established before(by a margin of about 2 hours), even when it happened > on the same calendar day. > > Calculating the precise solstice time for the year 1554 is left as an > exercise for the picky. > >
