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Old 12-03-2013, 09:35   #46
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Re: Sextants and celestial navigation

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Then what would you use? (Other than seeing a land mass, a DR or using something that requires the use of electrons?)

If your bored senseless, you could use Lunar distances, if you can them on paper, or, use the method of a series of sights taken before and after mer. pass, and graphically or by differential calculation, have a stab at working an approximate longitude from that.
I'll stick with a decent watch or clock.
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Old 12-03-2013, 09:52   #47
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Re: Sextants and celestial navigation

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If your bored senseless, you could use Lunar distances, if you can them on paper, or, use the method of a series of sights taken before and after mer. pass, and graphically or by differential calculation, have a stab at working an approximate longitude from that.
I'll stick with a decent watch or clock.

I second that. I am sort of celestial navigation junkie, when I am not on the boat I am taking sights from my balcony. Actually on my cutter GPS is back up. Even have those Norie's tables. But that lunar distances would be overkill, not to mention that to use that method you will have to have sun or bright stars lying close and parallel to the Moon's path every time. what if it is cloudy and you can take only moon sight. you have to wait for enough clear sky.

as you said, I will stick to my Casio.

and thanks one more time for that "corrections"
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Old 12-03-2013, 09:57   #48
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Re: Sextants and celestial navigation

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you will have to have sun or bright stars lying close and parallel to the Moon's path every time. what it is cloudy and you can take only moon sight. you have to wait for enough clear sky.
determining ones position is overrated , read Captains Sumners Log.

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Old 12-03-2013, 16:57   #49
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Re: Sextants and celestial navigation

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The beauty of celestial is that you need no electronics or modern technology, just an accurate time piece for determining longitude. If you want to be truly independent in determining your position (which is the whole point of celestial) then you want the paper sight reduction tables and the paper almanac.
Or you can buy Kolbe's Long Term Almanac and learn from that. See my earlier post for the sight form I developed for using the Almanac portion.

It is good until the year 2050. It is the only book you need for determing GHA and DEC for the sun and 40 stars. It also has sight reduction tables to enable you to reduce your sights to Hc and Zn for plotting, without a calculator.
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Old 13-03-2013, 05:56   #50
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Re: Sextants and celestial navigation

Yep. I will agree. The sextant, the chronometer, and the celestial tables. The pen and paper way. Solve the triangle and you are done.

Keep things simple and exercise.

b.
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