Re: Calendar {again}

jameshanley39@xxxxxxxxxxx wrote on 13 apr 2007 in
soc.culture.jewish.moderated:

On 12 Apr, 16:11, "Evertjan." <exjxw.hannivo...@xxxxxxxxxxxx> wrote:
jameshanle...@xxxxxxxxxxx wrote on 12 apr 2007 in
soc.culture.jewish.moderated:

Though apparently, on the equinox, day and night aren't equal
length
http://news.nationalgeographic.com/news/2004/03/0318_040318_equinox.h
tml
maybe it's just approximate.. but then i can't quite see how one
would get the exact date.

The equinox is a moment in time twice a year, not a day.
It is the moment the center of the sun is exactly on the equator
plain.

<http://en.wikipedia.org/wiki/Vernal_equinox>


since the equinox is when the earth/earth's axis isn't tilted towards
the sun, I suppose the ecliptic and the equator would be on the same
plane (or parallel - somewhat above or below). For I guess pretty much
at least a day..

No, since the sun is not a point but a large volume, it takes between 2
and 2.5 days for the equator plane from getting in the sun to getting out
again. [Geocentric thinking would say that the local midday sun was over
the equator]

But if it is not above or below. But is as you say, when the center of
the sun is on the equatorial plane, then, what did the rabbis do?
stand at the equator , open their pencil case, take out a protractor -
and measure "the angle" between the 'a' the plane made by a ray coming
from the center of the sun hitting earth hitting the equator, and 'b'
the equatorial plane, as 0?!

The rabbies, well the Sanhedrin, [originally composed of sadducees, later
perhaps farisees = rabbies] and even later replaced by beth dins, where
not all ignorami of the knowledge of the Babylon wizards/scientists.
[Compare also that the Egyptian priest/scientists, relying on Sirius had,
and likewize the far away in time and distance Stonehenge, apparatus that
could help find the correct date every year.]

For a nice story about the equinox problem around the time of Bar
Kochbah, and the effect on the Jewish calendar, read this:

<http://www.millenniummistake.net/tekst2.htm#secti3>

but it is very ambiguous on how the rabbis knew the date/time of the
vernal equinox.. It refers to them knowing many times, yet the lucid
article so naturally but implicitly cries "how", it skips over how, by
referring to it at one point as an "intuitive" understanding greater
than the romans, and at another point as"their competence" in adding
the extra month!!!

Perhaps the Jewish wars had decimated the people with more knowledge,
and they had to revert to their intuition. If the extra month was
incorrect, the next year would compensate for that easily. The prblem
after Bar Kochba was, that no central coordination was available and the
in the now absolute diaspora different conclusions could lead to
different calendars at the same time.

Usually the exact date where the equinox moment occured was not of great
importance, if the new moon date was not around that day, meseems.

I remember having read somewhere that before that time a semafore system
had existed to propagate the Sanhedrin date decisions that followed the
sighting of the new moon by two witnesses, over a large area quickly,
more quickly than older messenger system.

IMHO!!

--
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)
.

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