[Avodah] Where is the Molad announced for?

[Zev Sero]

On 22/12/20 8:16 pm, Micha Berger wrote:
> We don't know where the 0 deg meridian, "mei'emtza hayishuv" was in the
> Rambam's maps.

Well, we do.  24 degrees east of Y'm.  Rounded to the nearest degree, of 
course, since the maps weren't designed by Jews.

>  But, since more people testified in court from Bavel than
> from Egypt or points west, 

Nobody could possibly have come from Bavel to testify about the new 
moon. They couldn't have made it in time.  One would have to be Yaacov 
Avinu to do that trip in one day.


> It's weak, I know. But the alternative is leaving the Rambam at odds with
> Kepler. And I don't think we have to.

We don't have to assume the calculation was ever completely accurate, or 
ever intended to be precise.  Rounding is legitimate.  If those who 
first determined the length of a month rounded it to the nearest chelek 
they could have been at any time, including Moshe Rabbenu.  I don't 
think Moshe Rabbenu's month was long enough that it would be rounded to 
two chalakim instead of one.  And that justifies the tradition that this 
length is HLLMMS (although that term isn't always meant literally).

= = =
By the way, I don't think "Hayishuv" here means "civilization", but 
rather the upper hemisphere, which is inhabitable, as opposed to the 
lower hemisphere which is ocean and thus uninhabitable.

Before 1492 everyone thought the lower hemisphere was one vast ocean, 
and that's why nobody attempted to cross it.  Nobody (including 
Columbus) knew that there was a continent in the middle, dividing it 
into two oceans, and making the trip doable.

The geographers of the Rambam's day, apparently, had decided that the 
bounds of this upper hemisphere ran from about what we call 31 W to 149 
E, and put the zero meridian in the middle. So on those maps Y'm's 
coordinates were 24 E, 32 N.


-- 
Zev Sero            Wishing everyone a *healthy* and happy 5781
zev at sero.name       "May this year and its curses end
                      May a new year and its blessings begin"