[Avodah] international dateline

[Micha Berger]

On Thu, Jan 05, 2012 at 02:16:28PM -0500, Zev Sero wrote:
> BTW, R Shlomo Goren held that the dateline is at 149 E, which puts
> it approximately through Canberra, with Melbourne on the correct side
> but Sydney on the wrong side.

This is roughly 114deg east of J-m. (Y-m is at 34deg 48')

To explain... The Brisker Rav put the date line 90deg east of Y-m,
RSGoren is arguing it should be 90deg east of the middle of the yishuv,
which in turn is 24deg E of Y-m. R' Goren gets the location of the middle
of the yishuv from the Rambam, Hil Qiddush haChodesh 2:13.

I looked this up once in relation to the molad, and I think I saw it in
an RZS posting in Mail-Jewish from about a decade back. Evidence from our
current announcement of the molad, minus slipage in the millenia since
the Sanhedrin (both days and months are longer, but once you remove the
29 longer days, there are fewer chalaqim left to the molad), is that this
is roughly the meridian actually used when we speak of "J-m Standard
Time" for announcing the molad. The math points more to 23deg than 24,
but that is only because I assume that zero error was when they were
qov'im the calendar, and not some earlier time (eg the abandonment of
the Lishqas haGazis).

Tir'u baTov!
-Micha

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Micha Berger             I thank God for my handicaps, for, through them,
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