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Subject: Re: Sextant Positions versus Map Datums?
From: Rodney Myrvaagnes (rodneym@XXX.XXX)
Date: Tue Jan 15 2002 - 14:48:46 EST
On Tue, 15 Jan 2002 13:04:57 -0500, Jared Sherman wrote:
>If NAD27 and WGS84 disagree by a mile, then wouldn't the "most accurate" sextant position still either be off by a mile, or have been
off by a mile? Or maybe still be off wherever the map datum doesn't match a "spherical earth" model?
>
AFIK, the difference between those two particular datums isn't big enough to be detected in normal sextant use. The problem of
horizontal chart errors is more likely to occur with charts surveyed in isolation by Capt. Cook, for example.
It only matters when you are on soundings. When you can see one of these isolated islands it becomes piloting, whether you got there
with a sextand, a cross-staff, dangling testicles, or a GPS.
Rodney Myrvaagnes J36 Gjo/a
"Religious wisdom is to wisdom as military music is to music."
"What contemptible scoundrel stole the cork from my lunch?" -- W. C Fields
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