>From the table in the reference provided by Paul Hirose's post >(http://astro.ukho.gov.uk/nao/lvm/) , the uncertainty in delta-T is 0.4 hours. > At a latitude of 31 degrees, I compute a (1-sigma) distance of 500 km, which >the internet tells me is about as far away as Alexandria. Judging from the >eclipse trajectory as shown, it would have required a ~ 2.5-sigma deviation to >miss Canaan entirely, and another sigma of deviation to miss the Nile delta as >well, although the curvature of the plot means less and less of northern Egypt >would remain in the path as the visibility area moves west. Thebes is >outside of the depicted path already. I guess their sigma is reasonable, as >their figure 10 shows 180 seconds variation of Delta-T in modern times (since >1550).
But it certainly seems that if it was visible in Canaan, it should have been visible in the delta. -----Original Message----- From: LEAPSECS [mailto:leapsecs-boun...@leapsecond.com] On Behalf Of Poul-Henning Kamp Sent: Friday, November 03, 2017 3:21 PM To: Leap Second Discussion List; Steve Allen Subject: [Non-DoD Source] Re: [LEAPSECS] new delta-T data point -------- In message <20171103173224.ga10...@ucolick.org>, Steve Allen writes: >I'm a bit disturbed by the plotted path of that eclipse because it is >very wide and includes the entire Nile delta as well as modern >Palestine, Israel, Jordan, and Baghdad at sunset. Unless weather >prevented it, somebody else should have made a record of that eclipse. And they probably did, but it didn't survive or we havnt torn down the city built on top of it later. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com https://pairlist6.pair.net/mailman/listinfo/leapsecs
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